Diagnostic flags in Clang

Introduction

This page lists the diagnostic flags currently supported by Clang.

Diagnostic flags

-W

Synonym for -Wextra.

-W#pragma-messages

This diagnostic is enabled by default.

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-W#warnings

This diagnostic is enabled by default.

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-WCFString-literal

This diagnostic is enabled by default.

Diagnostic text:

warning: input conversion stopped due to an input byte that does not belong to the input codeset UTF-8

-WCL4

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wall, -Wextra.

-WIndependentClass-attribute

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘objc_independent_class’ attribute may be put on a typedef only; attribute is ignored

warning: ‘objc_independent_class’ attribute may be put on Objective-C object pointer type only; attribute is ignored

-WNSObject-attribute

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘NSObject’ attribute may be put on a typedef only; attribute is ignored

-Wabi

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wabsolute-value

This diagnostic is enabled by default.

Diagnostic text:

warning: absolute value function A given an argument of type B but has parameter of type C which may cause truncation of value

warning: taking the absolute value of 

pointer

function

array

 type B is suspicious

warning: taking the absolute value of unsigned type A has no effect

warning: using 

integer

floating point

complex

 absolute value function A when argument is of 

integer

floating point

complex

 type

-Wabstract-final-class

This diagnostic is enabled by default.

Diagnostic text:

warning: abstract class is marked ‘

final

sealed

-Wabstract-vbase-init

Diagnostic text:

warning: initializer for virtual base class A of abstract class B will never be used

-Waddress

This diagnostic is enabled by default.

Controls -Wpointer-bool-conversion, -Wstring-compare, -Wtautological-pointer-compare.

-Waddress-of-packed-member

This diagnostic is enabled by default.

Diagnostic text:

warning: taking address of packed member A of class or structure B may result in an unaligned pointer value

-Waddress-of-temporary

This diagnostic is an error by default, but the flag -Wno-address-of-temporary can be used to disable the error.

Diagnostic text:

error: taking the address of a temporary object of type A

-Waggregate-return

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wall

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wmisleading-indentation, -Wmost, -Wparentheses, -Wswitch, -Wswitch-bool.

-Walloca

Diagnostic text:

warning: use of function A is discouraged; there is no way to check for failure but failure may still occur, resulting in a possibly exploitable security vulnerability

-Walloca-with-align-alignof

This diagnostic is enabled by default.

Diagnostic text:

warning: second argument to __builtin_alloca_with_align is supposed to be in bits

-Wambiguous-delete

This diagnostic is enabled by default.

Diagnostic text:

warning: multiple suitable A functions for B; no ‘operator delete’ function will be invoked if initialization throws an exception

-Wambiguous-ellipsis

This diagnostic is enabled by default.

Diagnostic text:

warning: ’…’ in this location creates a C-style varargs function

, not a function parameter pack

-Wambiguous-macro

This diagnostic is enabled by default.

Diagnostic text:

warning: ambiguous expansion of macro A

-Wambiguous-member-template

This diagnostic is enabled by default.

Diagnostic text:

warning: lookup of A in member access expression is ambiguous; using member of B

-Wambiguous-reversed-operator

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++20 considers use of overloaded operator ‘A’ (with operand types B and C) to be ambiguous despite there being a unique best viable function

-Wanalyzer-incompatible-plugin

This diagnostic is enabled by default.

Diagnostic text:

warning: checker plugin ‘A’ is not compatible with this version of the analyzer

-Wanon-enum-enum-conversion

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-anon-enum-enum-conversion.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types

-Wanonymous-pack-parens

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++11 requires a parenthesized pack declaration to have a name

-Warc

This diagnostic is enabled by default.

Controls -Warc-non-pod-memaccess, -Warc-retain-cycles, -Warc-unsafe-retained-assign.

-Warc-bridge-casts-disallowed-in-nonarc

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ casts have no effect when not using ARC

-Warc-maybe-repeated-use-of-weak

Diagnostic text:

warning: weak 

variable

property

implicit property

instance variable

 B may be accessed multiple times in this 

function

method

block

lambda

 and may be unpredictably set to nil; assign to a strong variable to keep the object alive

-Warc-non-pod-memaccess

This diagnostic is enabled by default.

Diagnostic text:

warning: 

destination for

source of

 this B call is a pointer to ownership-qualified type C

-Warc-performSelector-leaks

This diagnostic is enabled by default.

Diagnostic text:

warning: performSelector may cause a leak because its selector is unknown

-Warc-repeated-use-of-weak

Also controls -Warc-maybe-repeated-use-of-weak.

Diagnostic text:

warning: weak 

variable

property

implicit property

instance variable

 B is accessed multiple times in this 

function

method

block

lambda

 but may be unpredictably set to nil; assign to a strong variable to keep the object alive

-Warc-retain-cycles

This diagnostic is enabled by default.

Diagnostic text:

warning: capturing A strongly in this block is likely to lead to a retain cycle

-Warc-unsafe-retained-assign

This diagnostic is enabled by default.

Diagnostic text:

warning: assigning 

array literal

dictionary literal

numeric literal

boxed expression

<should not happen>

block literal

 to a weak 

property

variable

; object will be released after assignment

warning: assigning retained object to 

weak

unsafe_unretained

 

property

variable

; object will be released after assignment

warning: assigning retained object to unsafe property; object will be released after assignment

-Wargument-outside-range

This diagnostic is an error by default, but the flag -Wno-argument-outside-range can be used to disable the error.

Diagnostic text:

error: argument value A is outside the valid range [B, C]

-Warray-bounds

This diagnostic is enabled by default.

Diagnostic text:

warning: array index A is past the end of the array (which contains B element

s

)

warning: array index A is before the beginning of the array

warning: array argument is too small; 

contains A elements

is of size A

, callee requires at least B

warning: ‘static’ has no effect on zero-length arrays

-Warray-bounds-pointer-arithmetic

Diagnostic text:

warning: the pointer incremented by A refers past the end of the array (that contains B element

s

)

warning: the pointer decremented by A refers before the beginning of the array

-Wasm

This diagnostic is enabled by default.

Controls -Wasm-ignored-qualifier, -Wasm-operand-widths.

-Wasm-ignored-qualifier

This diagnostic is enabled by default.

Diagnostic text:

warning: ignored A qualifier on asm

warning: meaningless ‘volatile’ on asm outside function

-Wasm-operand-widths

This diagnostic is enabled by default.

Diagnostic text:

warning: value size does not match register size specified by the constraint and modifier

-Wassign-enum

Diagnostic text:

warning: integer constant not in range of enumerated type A

-Wassume

This diagnostic is enabled by default.

Diagnostic text:

warning: the argument to A has side effects that will be discarded

-Wat-protocol

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Watimport-in-framework-header

This diagnostic is enabled by default.

Diagnostic text:

warning: use of ‘@import’ in framework header is discouraged, including this header requires -fmodules

-Watomic-alignment

This diagnostic is enabled by default.

Diagnostic text:

warning: 

large

misaligned

 atomic operation may incur significant performance penalty

-Watomic-implicit-seq-cst

Diagnostic text:

warning: implicit use of sequentially-consistent atomic may incur stronger memory barriers than necessary

-Watomic-memory-ordering

This diagnostic is enabled by default.

Diagnostic text:

warning: memory order argument to atomic operation is invalid

-Watomic-property-with-user-defined-accessor

This diagnostic is enabled by default.

Diagnostic text:

warning: writable atomic property A cannot pair a synthesized 

getter

setter

 with a user defined 

getter

setter

-Wattribute-packed-for-bitfield

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘packed’ attribute was ignored on bit-fields with single-byte alignment in older versions of GCC and Clang

-Wattributes

This diagnostic is enabled by default.

Controls -Wignored-attributes, -Wunknown-attributes.

-Wauto-disable-vptr-sanitizer

This diagnostic is enabled by default.

Diagnostic text:

warning: implicitly disabling vptr sanitizer because rtti wasn’t enabled

-Wauto-import

Diagnostic text:

warning: treating #

include

import

include_next

__include_macros

 as an import of module ‘B

-Wauto-storage-class

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘auto’ storage class specifier is not permitted in C++11, and will not be supported in future releases

-Wauto-var-id

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘auto’ deduced as ‘id’ in declaration of A

-Wavailability

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘unavailable’ availability overrides all other availability information

warning: ignoring availability attribute 

on ‘+load’ method

with constructor attribute

with destructor attribute

warning: only ‘unavailable’ and ‘deprecated’ are supported for Swift availability

warning: unknown platform A in availability macro

warning: feature cannot be 

introduced

deprecated

obsoleted

 in B version C before it was 

introduced

deprecated

obsoleted

 in version E; attribute ignored

warning: use same version number separators ‘_’ or ‘.’; as in ‘major[.minor[.subminor]]’

warning: availability does not match previous declaration

warning: 

overriding 

method 

introduced after

deprecated before

obsoleted before

 

the protocol method it implements

overridden method

 on B (C vs. D)

warning: 

overriding 

method cannot be unavailable on A when 

the protocol method it implements

its overridden method

 is available

-Wavr-rtlib-linking-quirks

This diagnostic is enabled by default.

Diagnostic text:

warning: support for linking stdlibs for microcontroller ‘A’ is not implemented

warning: no avr-gcc installation can be found on the system, cannot link standard libraries

warning: no avr-libc installation can be found on the system, cannot link standard libraries

warning: no target microcontroller specified on command line, cannot link standard libraries, please pass -mmcu=<mcu name>

warning: standard library not linked and so no interrupt vector table or compiler runtime routines will be linked

-Wbackend-plugin

This diagnostic is enabled by default.

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-Wbackslash-newline-escape

This diagnostic is enabled by default.

Diagnostic text:

warning: backslash and newline separated by space

-Wbad-function-cast

Diagnostic text:

warning: cast from function call of type A to non-matching type B

-Wbind-to-temporary-copy

Also controls -Wc++98-compat-bind-to-temporary-copy.

Diagnostic text:

warning: C++98 requires an accessible copy constructor for class C when binding a reference to a temporary; was 

private

protected

warning: no viable constructor 

copying variable

copying parameter

returning object

initializing statement expression result

throwing object

copying member subobject

copying array element

allocating object

copying temporary

initializing base subobject

initializing vector element

capturing value

 of type B; C++98 requires a copy constructor when binding a reference to a temporary

-Wbinding-in-condition

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++17 does not permit structured binding declaration in a condition

-Wbitfield-constant-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit truncation from C to bit-field changes value from A to B

-Wbitfield-enum-conversion

Diagnostic text:

warning: bit-field A is not wide enough to store all enumerators of B

warning: signed bit-field A needs an extra bit to represent the largest positive enumerators of B

warning: assigning value of signed enum type B to unsigned bit-field A; negative enumerators of enum B will be converted to positive values

-Wbitfield-width

This diagnostic is enabled by default.

Diagnostic text:

warning: width of anonymous bit-field (A bits) exceeds width of its type; value will be truncated to B bit

s

warning: width of bit-field A (B bits) exceeds the width of its type; value will be truncated to C bit

s

-Wbitwise-conditional-parentheses

This diagnostic is enabled by default.

Diagnostic text:

warning: operator ‘?:’ has lower precedence than ‘A’; ‘A’ will be evaluated first

-Wbitwise-op-parentheses

Diagnostic text:

warning: A’ within ‘B

-Wblock-capture-autoreleasing

This diagnostic is enabled by default.

Diagnostic text:

warning: block captures an autoreleasing out-parameter, which may result in use-after-free bugs

-Wbool-conversion

This diagnostic is enabled by default.

Also controls -Wpointer-bool-conversion, -Wundefined-bool-conversion.

Diagnostic text:

warning: initialization of pointer of type A to null from a constant boolean expression

-Wbool-operation

This diagnostic is enabled by default.

Diagnostic text:

warning: bitwise negation of a boolean expression

;

 always evaluates to ‘true’;

 did you mean logical negation?

-Wbraced-scalar-init

This diagnostic is enabled by default.

Diagnostic text:

warning: braces around scalar initializer

-Wbridge-cast

This diagnostic is enabled by default.

Diagnostic text:

warning: A bridges to B, not C

warning: A cannot bridge to B

-Wbuiltin-assume-aligned-alignment

This diagnostic is enabled by default.

Diagnostic text:

warning: requested alignment must be A bytes or smaller; maximum alignment assumed

-Wbuiltin-macro-redefined

This diagnostic is enabled by default.

Diagnostic text:

warning: redefining builtin macro

warning: undefining builtin macro

-Wbuiltin-memcpy-chk-size

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ will always overflow; destination buffer has size B, but size argument is C

-Wbuiltin-requires-header

This diagnostic is enabled by default.

Diagnostic text:

warning: declaration of built-in function ‘B’ requires inclusion of the header <A>

-Wc++-compat

Diagnostic text:

warning: 

empty 

struct

union

 has size 0 in C, 

size 1

non-zero size

 in C++

-Wc++11-compat

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++11-compat-deprecated-writable-strings, -Wc++11-compat-reserved-user-defined-literal, -Wc++11-narrowing, -Wc++98-c++11-c++14-c++17-compat, -Wc++98-c++11-c++14-compat, -Wc++98-c++11-compat.

Diagnostic text:

warning: integer literal is too large to be represented in type ‘long’ and is subject to undefined behavior under C++98, interpreting as ‘unsigned long’; this literal will 

have type ‘long long’

be ill-formed

 in C++11 onwards

warning: ‘auto’ storage class specifier is redundant and incompatible with C++11

warning: identifier after literal will be treated as a user-defined literal suffix in C++11

warning: A’ is a keyword in C++11

warning: use of right-shift operator (‘>>’) in template argument will require parentheses in C++11

warning: explicit instantiation cannot be ‘inline’

warning: explicit instantiation of A must occur at global scope

warning: explicit instantiation of A not in a namespace enclosing B

warning: explicit instantiation of A must occur in namespace B

warning: integer literal is too large to be represented in type ‘long’, interpreting as ‘unsigned long’ per C++98; this literal will 

have type ‘long long’

be ill-formed

 in C++11 onwards

-Wc++11-compat-deprecated-writable-strings

This diagnostic is enabled by default.

Diagnostic text:

warning: conversion from string literal to A is deprecated

-Wc++11-compat-reserved-user-defined-literal

Diagnostic text:

warning: identifier after literal will be treated as a reserved user-defined literal suffix in C++11

-Wc++11-extensions

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++11-extra-semi, -Wc++11-inline-namespace, -Wc++11-long-long.

Diagnostic text:

warning: alias declarations are a C++11 extension

warning: implicit conversion from array size expression of type A to 

integral

enumeration

 type C is a C++11 extension

warning: ‘auto’ type specifier is a C++11 extension

warning: enumeration types with a fixed underlying type are a C++11 extension

warning: 

defaulted

deleted

 function definitions are a C++11 extension

warning: befriending enumeration type A is a C++11 extension

warning: commas at the end of enumerator lists are a C++11 extension

warning: explicit conversion functions are a C++11 extension

warning: extern templates are a C++11 extension

warning: range-based for loop is a C++11 extension

warning: generalized initializer lists are a C++11 extension

warning: use of enumeration in a nested name specifier is a C++11 extension

warning: non-class friend type A is a C++11 extension

warning: in-class initialization of non-static data member is a C++11 extension

warning: A’ keyword is a C++11 extension

warning: reference qualifiers on functions are a C++11 extension

warning: rvalue references are a C++11 extension

warning: scoped enumerations are a C++11 extension

warning: static data member A in union is a C++11 extension

warning: non-type template argument referring to 

function

object

 B with internal linkage is a C++11 extension

warning: ‘template’ keyword outside of a template

warning: default template arguments for a function template are a C++11 extension

warning: ‘typename’ occurs outside of a template

warning: unelaborated friend declaration is a C++11 extension; specify ‘

struct

interface

union

class

enum

‘ to befriend B

warning: variadic templates are a C++11 extension

-Wc++11-extra-semi

Diagnostic text:

warning: extra ‘;’ outside of a function is a C++11 extension

-Wc++11-inline-namespace

This diagnostic is enabled by default.

Diagnostic text:

warning: inline namespaces are a C++11 feature

-Wc++11-long-long

Diagnostic text:

warning: ‘long long’ is a C++11 extension

-Wc++11-narrowing

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

error: 

case value

enumerator value

non-type template argument

array size

constexpr if condition

explicit specifier argument

 

cannot be narrowed from type C to D

evaluates to C, which cannot be narrowed to type D

error: constant expression evaluates to A which cannot be narrowed to type B

error: type A cannot be narrowed to B in initializer list

error: non-constant-expression cannot be narrowed from type A to B in initializer list

warning: constant expression evaluates to A which cannot be narrowed to type B in C++11

warning: type A cannot be narrowed to B in initializer list in C++11

warning: non-constant-expression cannot be narrowed from type A to B in initializer list in C++11

-Wc++14-binary-literal

Diagnostic text:

warning: binary integer literals are a C++14 extension

-Wc++14-extensions

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++14-binary-literal.

Diagnostic text:

warning: use of this statement in a constexpr 

function

constructor

 is a C++14 extension

warning: multiple return statements in constexpr function is a C++14 extension

warning: variable declaration in a constexpr 

function

constructor

 is a C++14 extension

warning: type definition in a constexpr 

function

constructor

 is a C++14 extension

warning: use of the A attribute is a C++14 extension

warning: ‘decltype(auto)’ type specifier is a C++14 extension

warning: initialized lambda captures are a C++14 extension

warning: variable templates are a C++14 extension

-Wc++17-compat

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wc++17-compat-mangling, -Wc++98-c++11-c++14-c++17-compat, -Wdeprecated-increment-bool, -Wdeprecated-register.

-Wc++17-compat-mangling

This diagnostic is enabled by default.

Diagnostic text:

warning: mangled name of A will change in C++17 due to non-throwing exception specification in function signature

-Wc++17-compat-pedantic

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wc++17-compat, -Wc++98-c++11-c++14-c++17-compat-pedantic.

-Wc++17-extensions

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: ISO C++ standards before C++17 do not allow new expression for type A to use list-initialization

warning: constexpr if is a C++17 extension

warning: ‘constexpr’ on lambda expressions is a C++17 extension

warning: use of the A attribute is a C++17 extension

warning: decomposition declarations are a C++17 extension

warning: pack fold expression is a C++17 extension

warning: ‘begin’ and ‘end’ returning different types (A and B) is a C++17 extension

warning: hexadecimal floating literals are a C++17 feature

warning: 

if

switch

‘ initialization statements are a C++17 extension

warning: inline variables are a C++17 extension

warning: use of multiple declarators in a single using declaration is a C++17 extension

warning: nested namespace definition is a C++17 extension; define each namespace separately

warning: attributes on 

a namespace

an enumerator

 declaration are a C++17 extension

warning: capture of ‘*this’ by copy is a C++17 extension

warning: static_assert with no message is a C++17 extension

warning: template template parameter using ‘typename’ is a C++17 extension

warning: default scope specifier for attributes is a C++17 extension

warning: pack expansion of using declaration is a C++17 extension

-Wc++20-compat

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: ‘consteval’ specifier is incompatible with C++ standards before C++20

warning: ‘constinit’ specifier is incompatible with C++ standards before C++20

warning: aggregate initialization of type A with user-declared constructors is incompatible with C++20

warning: this expression will be parsed as explicit(bool) in C++20

warning: ’<=>’ is a single token in C++20; add a space to avoid a change in behavior

warning: type of UTF-8 string literal will change from array of const char to array of const char8_t in C++20

warning: A’ is a keyword in C++20

-Wc++20-designator

Diagnostic text:

warning: designated initializers are a C++20 extension

-Wc++20-extensions

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++20-designator.

Diagnostic text:

warning: use of function template name with no prior declaration in function call with explicit template arguments is a C++20 extension

warning: default member initializer for bit-field is a C++20 extension

warning: use of this statement in a constexpr 

function

constructor

 is a C++20 extension

warning: constexpr constructor that does not initialize all members is a C++20 extension

warning: function try block in constexpr 

function

constructor

 is a C++20 extension

warning: uninitialized variable in a constexpr 

function

constructor

 is a C++20 extension

warning: constexpr union constructor that does not initialize any member is a C++20 extension

warning: use of the A attribute is a C++20 extension

warning: decomposition declaration declared 

B

with ‘B’ specifiers

 is a C++20 extension

warning: defaulted comparison operators are a C++20 extension

warning: explicit capture of ‘this’ with a capture default of ‘=’ is a C++20 extension

warning: explicit(bool) is a C++20 extension

warning: range-based for loop initialization statements are a C++20 extension

warning: initialized lambda pack captures are a C++20 extension

warning: inline nested namespace definition is a C++20 extension

warning: explicit template parameter list for lambdas is a C++20 extension

warning: invoking a pointer to a ‘const &’ member function on an rvalue is a C++20 extension

-Wc++98-c++11-c++14-c++17-compat

Diagnostic text:

warning: use of function template name with no prior function template declaration in function call with explicit template arguments is incompatible with C++ standards before C++20

warning: default member initializer for bit-field is incompatible with C++ standards before C++20

warning: use of this statement in a constexpr 

function

constructor

 is incompatible with C++ standards before C++20

warning: constexpr constructor that does not initialize all members is incompatible with C++ standards before C++20

warning: function try block in constexpr 

function

constructor

 is incompatible with C++ standards before C++20

warning: uninitialized variable in a constexpr 

function

constructor

 is incompatible with C++ standards before C++20

warning: constexpr union constructor that does not initialize any member is incompatible with C++ standards before C++20

warning: virtual constexpr functions are incompatible with C++ standards before C++20

warning: decomposition declaration declared 

B

with ‘B’ specifiers

 is incompatible with C++ standards before C++20

warning: defaulted comparison operators are incompatible with C++ standards before C++20

warning: explicitly defaulting this 

default constructor

copy constructor

move constructor

copy assignment operator

move assignment operator

destructor

 with a type different from the implicit type is incompatible with C++ standards before C++20

warning: explicit capture of ‘this’ with a capture default of ‘=’ is incompatible with C++ standards before C++20

warning: explicit(bool) is incompatible with C++ standards before C++20

warning: range-based for loop initialization statements are incompatible with C++ standards before C++20

warning: initialized lambda capture packs are incompatible with C++ standards before C++20

warning: inline nested namespace definition is incompatible with C++ standards before C++20

warning: 

default construction

assignment

 of lambda is incompatible with C++ standards before C++20

warning: explicit template parameter list for lambdas is incompatible with C++ standards before C++20

warning: ’<=>’ operator is incompatible with C++ standards before C++20

warning: ‘char8_t’ type specifier is incompatible with C++ standards before C++20

-Wc++98-c++11-c++14-c++17-compat-pedantic

Also controls -Wc++98-c++11-c++14-c++17-compat.

Diagnostic text:

warning: designated initializers are incompatible with C++ standards before C++20

warning: invoking a pointer to a ‘const &’ member function on an rvalue is incompatible with C++ standards before C++20

-Wc++98-c++11-c++14-compat

Diagnostic text:

warning: class template argument deduction is incompatible with C++ standards before C++17

; for compatibility, use explicit type name B

warning: constexpr if is incompatible with C++ standards before C++17

warning: constexpr on lambda expressions is incompatible with C++ standards before C++17

warning: decomposition declarations are incompatible with C++ standards before C++17

warning: pack fold expression is incompatible with C++ standards before C++17

warning: 

if

switch

 initialization statements are incompatible with C++ standards before C++17

warning: inline variables are incompatible with C++ standards before C++17

warning: nested namespace definition is incompatible with C++ standards before C++17

warning: by value capture of ‘*this’ is incompatible with C++ standards before C++17

warning: static_assert with no message is incompatible with C++ standards before C++17

warning: non-type template parameters declared with A are incompatible with C++ standards before C++17

warning: template template parameter using ‘typename’ is incompatible with C++ standards before C++17

warning: unicode literals are incompatible with C++ standards before C++17

warning: default scope specifier for attributes is incompatible with C++ standards before C++17

warning: use of multiple declarators in a single using declaration is incompatible with C++ standards before C++17

warning: pack expansion using declaration is incompatible with C++ standards before C++17

warning: ‘begin’ and ‘end’ returning different types (A and B) is incompatible with C++ standards before C++17

-Wc++98-c++11-c++14-compat-pedantic

Also controls -Wc++98-c++11-c++14-compat.

Diagnostic text:

warning: attributes on 

a namespace

an enumerator

 declaration are incompatible with C++ standards before C++17

warning: hexadecimal floating literals are incompatible with C++ standards before C++17

-Wc++98-c++11-compat

Diagnostic text:

warning: use of this statement in a constexpr 

function

constructor

 is incompatible with C++ standards before C++14

warning: multiple return statements in constexpr function is incompatible with C++ standards before C++14

warning: constexpr function with no return statements is incompatible with C++ standards before C++14

warning: variable declaration in a constexpr 

function

constructor

 is incompatible with C++ standards before C++14

warning: type definition in a constexpr 

function

constructor

 is incompatible with C++ standards before C++14

warning: ‘decltype(auto)’ type specifier is incompatible with C++ standards before C++14

warning: return type deduction is incompatible with C++ standards before C++14

warning: digit separators are incompatible with C++ standards before C++14

warning: generic lambdas are incompatible with C++11

warning: initialized lambda captures are incompatible with C++ standards before C++14

warning: variable templates are incompatible with C++ standards before C++14

-Wc++98-c++11-compat-binary-literal

Diagnostic text:

warning: binary integer literals are incompatible with C++ standards before C++14

-Wc++98-compat

Also controls -Wc++98-c++11-c++14-c++17-compat, -Wc++98-c++11-c++14-compat, -Wc++98-c++11-compat, -Wc++98-compat-local-type-template-args, -Wc++98-compat-unnamed-type-template-args.

Diagnostic text:

warning: alias declarations are incompatible with C++98

warning: ‘alignas’ is incompatible with C++98

warning: alignof expressions are incompatible with C++98

warning: C++11 attribute syntax is incompatible with C++98

warning: ‘auto’ type specifier is incompatible with C++98

warning: ‘constexpr’ specifier is incompatible with C++98

warning: constructor call from initializer list is incompatible with C++98

warning: ‘decltype’ type specifier is incompatible with C++98

warning: 

defaulted

deleted

 function definitions are incompatible with C++98

warning: delegating constructors are incompatible with C++98

warning: scalar initialized from empty initializer list is incompatible with C++98

warning: enumeration types with a fixed underlying type are incompatible with C++98

warning: befriending enumeration type A is incompatible with C++98

warning: enumeration type in nested name specifier is incompatible with C++98

warning: explicit conversion functions are incompatible with C++98

warning: range-based for loop is incompatible with C++98

warning: friend declaration naming a member of the declaring class is incompatible with C++98

warning: generalized initializer lists are incompatible with C++98

warning: jump from this goto statement to its label is incompatible with C++98

warning: jump from this 

indirect

asm

 goto statement to one of its possible targets is incompatible with C++98

warning: initialization of initializer_list object is incompatible with C++98

warning: inline namespaces are incompatible with C++98

warning: lambda expressions are incompatible with C++98

warning: ’<::’ is treated as digraph ‘<:’ (aka ‘[‘) followed by ‘:’ in C++98

warning: literal operators are incompatible with C++98

warning: universal character name referring to a control character is incompatible with C++98

warning: specifying character ‘A’ with a universal character name is incompatible with C++98

warning: noexcept specifications are incompatible with C++98

warning: noexcept expressions are incompatible with C++98

warning: use of non-static data member A in an unevaluated context is incompatible with C++98

warning: non-class friend type A is incompatible with C++98

warning: in-class initialization of non-static data members is incompatible with C++98

warning: 

anonymous struct

union

 member B with a non-trivial 

default constructor

copy constructor

move constructor

copy assignment operator

move assignment operator

destructor

 is incompatible with C++98

warning: ‘nullptr’ is incompatible with C++98

warning: A’ keyword is incompatible with C++98

warning: passing object of trivial but non-POD type A through variadic 

function

block

method

constructor

 is incompatible with C++98

warning: raw string literals are incompatible with C++98

warning: reference qualifiers on functions are incompatible with C++98

warning: reference initialized from initializer list is incompatible with C++98

warning: rvalue references are incompatible with C++98

warning: scoped enumerations are incompatible with C++98

warning: substitution failure due to access control is incompatible with C++98

warning: static_assert declarations are incompatible with C++98

warning: static data member A in union is incompatible with C++98

warning: jump from switch statement to this case label is incompatible with C++98

warning: redundant parentheses surrounding address non-type template argument are incompatible with C++98

warning: use of null pointer as non-type template argument is incompatible with C++98

warning: non-type template argument referring to 

function

object

 B with internal linkage is incompatible with C++98

warning: use of ‘template’ keyword outside of a template is incompatible with C++98

warning: default template arguments for a function template are incompatible with C++98

warning: trailing return types are incompatible with C++98

warning: consecutive right angle brackets are incompatible with C++98 (use ‘> >’)

warning: use of ‘typename’ outside of a template is incompatible with C++98

warning: befriending B without ‘

struct

interface

union

class

enum

‘ keyword is incompatible with C++98

warning: using this character in an identifier is incompatible with C++98

warning: unicode literals are incompatible with C++98

warning: A’ type specifier is incompatible with C++98

warning: inheriting constructors are incompatible with C++98

warning: variadic templates are incompatible with C++98

-Wc++98-compat-bind-to-temporary-copy

Diagnostic text:

warning: 

copying variable

copying parameter

returning object

initializing statement expression result

throwing object

copying member subobject

copying array element

allocating object

copying temporary

initializing base subobject

initializing vector element

capturing value

 of type C when binding a reference to a temporary would 

invoke an inaccessible constructor

find no viable constructor

find ambiguous constructors

invoke a deleted constructor

 in C++98

-Wc++98-compat-extra-semi

Diagnostic text:

warning: extra ‘;’ outside of a function is incompatible with C++98

-Wc++98-compat-local-type-template-args

Diagnostic text:

warning: local type A as template argument is incompatible with C++98

-Wc++98-compat-pedantic

Also controls -Wc++98-c++11-c++14-c++17-compat-pedantic, -Wc++98-c++11-c++14-compat-pedantic, -Wc++98-c++11-compat-pedantic, -Wc++98-compat, -Wc++98-compat-bind-to-temporary-copy, -Wc++98-compat-extra-semi.

Diagnostic text:

warning: implicit conversion from array size expression of type A to 

integral

enumeration

 type C is incompatible with C++98

warning: cast between pointer-to-function and pointer-to-object is incompatible with C++98

warning: empty macro arguments are incompatible with C++98

warning: commas at the end of enumerator lists are incompatible with C++98

warning: extern templates are incompatible with C++98

warning: ‘long long’ is incompatible with C++98

warning: C++98 requires newline at end of file

warning: #line number greater than 32767 is incompatible with C++98

warning: variadic macros are incompatible with C++98

-Wc++98-compat-unnamed-type-template-args

Diagnostic text:

warning: unnamed type as template argument is incompatible with C++98

-Wc11-extensions

Diagnostic text:

warning: anonymous unions are a C11 extension

warning: anonymous structs are a C11 extension

warning: A’ is a C11 extension

-Wc99-compat

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: 

using this character in an identifier

starting an identifier with this character

 is incompatible with C99

warning: unicode literals are incompatible with C99

warning: integer literal is too large to be represented in type ‘long’, interpreting as ‘unsigned long’ per C89; this literal will 

have type ‘long long’

be ill-formed

 in C99 onwards

-Wc99-designator

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++20-designator.

Diagnostic text:

warning: designated initializers are a C99 feature

warning: array designators are a C99 extension

warning: mixture of designated and non-designated initializers in the same initializer list is a C99 extension

warning: nested designators are a C99 extension

-Wc99-extensions

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc99-designator.

Diagnostic text:

warning: initializer for aggregate is not a compile-time constant

warning: 

qualifier in 

static 

array size 

‘[*] ‘

is a C99 feature

warning: compound literals are a C99-specific feature

warning: A’ is a C99 extension

warning: flexible array members are a C99 feature

warning: variable declaration in for loop is a C99-specific feature

warning: ISO C99 requires whitespace after the macro name

warning: empty macro arguments are a C99 feature

warning: commas at the end of enumerator lists are a C99-specific feature

warning: hexadecimal floating constants are a C99 feature

-Wcall-to-pure-virtual-from-ctor-dtor

This diagnostic is enabled by default.

Diagnostic text:

warning: call to pure virtual member function A has undefined behavior; overrides of A in subclasses are not available in the 

constructor

destructor

 of C

-Wcast-align

Diagnostic text:

warning: cast from A to B increases required alignment from C to D

-Wcast-calling-convention

This diagnostic is enabled by default.

Diagnostic text:

warning: cast between incompatible calling conventions ‘A’ and ‘B’; calls through this pointer may abort at runtime

-Wcast-of-sel-type

This diagnostic is enabled by default.

Diagnostic text:

warning: cast of type A to B is deprecated; use sel_getName instead

-Wcast-qual

Diagnostic text:

warning: cast from A to B drops 

const and volatile qualifiers

const qualifier

volatile qualifier

warning: cast from A to B must have all intermediate pointers const qualified to be safe

-Wcast-qual-unrelated

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++ does not allow 

const_cast

static_cast

reinterpret_cast

dynamic_cast

C-style cast

functional-style cast

 from B to C because it casts away qualifiers, even though the source and destination types are unrelated

-Wchar-align

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wchar-subscripts

Diagnostic text:

warning: array section 

lower bound

length

 is of type ‘char’

warning: array subscript is of type ‘char’

-Wclang-cl-pch

This diagnostic is enabled by default.

Diagnostic text:

warning: support for ‘/Yc’ with more than one source file not implemented yet; flag ignored

warning: support for ‘/Yc’ and ‘/Yu’ with different filenames not implemented yet; flags ignored

warning: #pragma hdrstop filename not supported, /Fp can be used to specify precompiled header filename

warning: definition of macro A does not match definition in precompiled header

-Wclass-varargs

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wnon-pod-varargs.

Diagnostic text:

warning: passing object of class type A through variadic 

function

block

method

constructor

; did you mean to call ‘D’?

-Wcomma

Diagnostic text:

warning: possible misuse of comma operator here

-Wcomment

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: escaped newline between */ characters at block comment end

warning: // comments are not allowed in this language

warning: multi-line // comment

warning: ’/*’ within block comment

-Wcomments

Synonym for -Wcomment.

-Wcompare-distinct-pointer-types

This diagnostic is enabled by default.

Diagnostic text:

warning: comparison of distinct pointer types

-Wcomplex-component-init

Diagnostic text:

warning: complex initialization specifying real and imaginary components is an extension

-Wconcepts-ts-compat

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++20 does not permit the ‘bool’ keyword after ‘concept’

-Wconditional-type-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: pointer/integer type mismatch in conditional expression

-Wconditional-uninitialized

Diagnostic text:

warning: variable A may be uninitialized when 

used here

captured by block

-Wconfig-macros

This diagnostic is enabled by default.

Diagnostic text:

warning: 

definition

#undef

 of configuration macro ‘B’ has no effect on the import of ‘C’; pass ‘

-DB=…

-UB

‘ on the command line to configure the module

-Wconstant-conversion

This diagnostic is enabled by default.

Also controls -Wbitfield-constant-conversion, -Wobjc-bool-constant-conversion.

Diagnostic text:

warning: implicit conversion from C to D changes value from A to B

-Wconstant-evaluated

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ will always evaluate to ‘true’ in a manifestly constant-evaluated expression

-Wconstant-logical-operand

This diagnostic is enabled by default.

Diagnostic text:

warning: use of logical ‘A’ with constant operand

-Wconstexpr-not-const

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘constexpr’ non-static member function will not be implicitly ‘const’ in C++14; add ‘const’ to avoid a change in behavior

-Wconsumed

Diagnostic text:

warning: consumed analysis attribute is attached to member of class ‘A’ which isn’t marked as consumable

warning: state of variable ‘A’ must match at the entry and exit of loop

warning: parameter ‘A’ not in expected state when the function returns: expected ‘B’, observed ‘C

warning: argument not in expected state; expected ‘A’, observed ‘B

warning: return state set for an unconsumable type ‘A

warning: return value not in expected state; expected ‘A’, observed ‘B

warning: invalid invocation of method ‘A’ on object ‘B’ while it is in the ‘C’ state

warning: invalid invocation of method ‘A’ on a temporary object while it is in the ‘B’ state

-Wconversion

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wbitfield-enum-conversion, -Wbool-conversion, -Wconstant-conversion, -Wenum-conversion, -Wfloat-conversion, -Wimplicit-float-conversion, -Wimplicit-int-conversion, -Wint-conversion, -Wliteral-conversion, -Wnon-literal-null-conversion, -Wnull-conversion, -Wobjc-literal-conversion, -Wshorten-64-to-32, -Wsign-conversion, -Wstring-conversion.

Diagnostic text:

warning: implicit conversion discards imaginary component: A to B

warning: implicit conversion turns vector to scalar: A to B

warning: passing non-generic address space pointer to A may cause dynamic conversion affecting performance

warning: non-type template argument with value ‘A’ converted to ‘B’ for unsigned template parameter of type C

warning: non-type template argument value ‘A’ truncated to ‘B’ for template parameter of type C

-Wcoroutine-missing-unhandled-exception

This diagnostic is enabled by default.

Diagnostic text:

warning: A is required to declare the member ‘unhandled_exception()’ when exceptions are enabled

-Wcovered-switch-default

Diagnostic text:

warning: default label in switch which covers all enumeration values

-Wcpp

Synonym for -W#warnings.

-Wcstring-format-directive

Diagnostic text:

warning: using A directive in 

NSString

CFString

 which is being passed as a formatting argument to the formatting 

method

CFfunction

-Wctad-maybe-unsupported

Diagnostic text:

warning: A may not intend to support class template argument deduction

-Wctor-dtor-privacy

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wctu

This diagnostic is enabled by default.

Diagnostic text:

warning: imported AST from ‘A’ had been generated for a different target, current: B, imported: C

-Wcuda-compat

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: A attribute parameter B is negative and will be ignored

warning: nvcc does not allow ‘__A__’ to appear after ‘()’ in lambdas

warning: ignored ‘inline’ attribute on kernel function A

warning: kernel function A is a member function; this may not be accepted by nvcc

warning: argument to ‘#pragma unroll’ should not be in parentheses in CUDA C/C++

-Wcustom-atomic-properties

Diagnostic text:

warning: atomic by default property A has a user defined 

getter

setter

 (property should be marked ‘atomic’ if this is intended)

-Wdangling

This diagnostic is enabled by default.

Also controls -Wdangling-field, -Wdangling-gsl, -Wdangling-initializer-list, -Wreturn-stack-address.

Diagnostic text:

warning: 

temporary 

whose address is used as value of

implicitly 

bound to

 

reference 

member of local variable

local 

variable

reference

array backing 

initializer list subobject of local variable

local initializer list

 

D 

will be destroyed at the end of the full-expression

warning: sorry, lifetime extension of 

temporary

backing array of initializer list

 created by aggregate initialization using default member initializer is not supported; lifetime of 

temporary

backing array

 will end at the end of the full-expression

-Wdangling-else

This diagnostic is enabled by default.

Diagnostic text:

warning: add explicit braces to avoid dangling else

-Wdangling-field

This diagnostic is enabled by default.

Diagnostic text:

warning: binding reference member A to stack allocated 

variable

parameter

 B

warning: 

reference

backing array for ‘std::initializer_list’

 

subobject of 

member A 

binds to

is

 a temporary object whose lifetime is shorter than the lifetime of the constructed object

warning: initializing pointer member A with the stack address of 

variable

parameter

 B

warning: temporary bound to reference member of allocated object will be destroyed at the end of the full-expression

-Wdangling-gsl

This diagnostic is enabled by default.

Diagnostic text:

warning: object backing the pointer will be destroyed at the end of the full-expression

warning: initializing pointer member A to point to a temporary object whose lifetime is shorter than the lifetime of the constructed object

-Wdangling-initializer-list

This diagnostic is enabled by default.

Diagnostic text:

warning: array backing 

initializer list subobject of the allocated object

the allocated initializer list

 will be destroyed at the end of the full-expression

-Wdarwin-sdk-settings

This diagnostic is enabled by default.

Diagnostic text:

warning: SDK settings were ignored as ‘SDKSettings.json’ could not be parsed

-Wdate-time

Diagnostic text:

warning: expansion of date or time macro is not reproducible

-Wdealloc-in-category

This diagnostic is enabled by default.

Diagnostic text:

warning: -dealloc is being overridden in a category

-Wdebug-compression-unavailable

This diagnostic is enabled by default.

Diagnostic text:

warning: cannot compress debug sections (zlib not installed)

-Wdeclaration-after-statement

Diagnostic text:

warning: ISO C90 forbids mixing declarations and code

-Wdefaulted-function-deleted

This diagnostic is enabled by default.

Diagnostic text:

warning: explicitly defaulted 

<ERROR>

equality

three-way

equality

relational

 comparison operator is implicitly deleted

warning: explicitly defaulted 

default constructor

copy constructor

move constructor

copy assignment operator

move assignment operator

destructor

 is implicitly deleted

-Wdelegating-ctor-cycles

This diagnostic is an error by default, but the flag -Wno-delegating-ctor-cycles can be used to disable the error.

Diagnostic text:

error: constructor for A creates a delegation cycle

-Wdelete-abstract-non-virtual-dtor

This diagnostic is enabled by default.

Diagnostic text:

warning: 

delete

destructor

 called on B that is abstract but has non-virtual destructor

-Wdelete-incomplete

This diagnostic is enabled by default.

Diagnostic text:

warning: cannot delete expression with pointer-to-‘void’ type A

warning: deleting pointer to incomplete type A may cause undefined behavior

-Wdelete-non-abstract-non-virtual-dtor

Diagnostic text:

warning: 

delete

destructor

 called on non-final B that has virtual functions but non-virtual destructor

-Wdelete-non-virtual-dtor

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wdelete-abstract-non-virtual-dtor, -Wdelete-non-abstract-non-virtual-dtor.

-Wdeprecated

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-anon-enum-enum-conversion, -Wdeprecated-array-compare, -Wdeprecated-attributes, -Wdeprecated-comma-subscript, -Wdeprecated-copy, -Wdeprecated-copy-dtor, -Wdeprecated-declarations, -Wdeprecated-dynamic-exception-spec, -Wdeprecated-enum-compare, -Wdeprecated-enum-compare-conditional, -Wdeprecated-enum-enum-conversion, -Wdeprecated-enum-float-conversion, -Wdeprecated-increment-bool, -Wdeprecated-register, -Wdeprecated-this-capture, -Wdeprecated-volatile, -Wdeprecated-writable-strings.

Diagnostic text:

warning: -O4 is equivalent to -O3

warning: access declarations are deprecated; use using declarations instead

warning: out-of-line definition of constexpr static data member is redundant in C++17 and is deprecated

warning: argument ‘A’ is deprecated, use ‘B’ instead

warning: treating ‘A’ input as ‘B’ when in C++ mode, this behavior is deprecated

warning: -fconcepts-ts is deprecated - use ‘-std=c++20’ for Concepts support

warning: OpenCL version A does not support the option ‘B

warning: Use of ‘long’ with ‘__vector’ is deprecated

-Wdeprecated-anon-enum-enum-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types is deprecated

-Wdeprecated-array-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: comparison between two arrays is deprecated; to compare array addresses, use unary ‘+’ to decay operands to pointers

-Wdeprecated-attributes

This diagnostic is enabled by default.

Diagnostic text:

warning: specifying vector types with the ‘mode’ attribute is deprecated; use the ‘vector_size’ attribute instead

-Wdeprecated-comma-subscript

This diagnostic is enabled by default.

Diagnostic text:

warning: top-level comma expression in array subscript is deprecated

-Wdeprecated-copy

Diagnostic text:

warning: definition of implicit copy 

constructor

assignment operator

 for A is deprecated because it has a user-declared copy 

assignment operator

constructor

-Wdeprecated-copy-dtor

Diagnostic text:

warning: definition of implicit copy 

constructor

assignment operator

 for A is deprecated because it has a user-declared destructor

-Wdeprecated-declarations

This diagnostic is enabled by default.

Diagnostic text:

warning: specifying ‘uuid’ as an ATL attribute is deprecated; use __declspec instead

warning: use of C-style parameters in Objective-C method declarations is deprecated

warning: A is deprecated

warning: A may be deprecated because the receiver type is unknown

warning: A is deprecated: B

warning: property access is using A method which is deprecated

-Wdeprecated-dynamic-exception-spec

Diagnostic text:

warning: dynamic exception specifications are deprecated

-Wdeprecated-enum-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types is deprecated

-Wdeprecated-enum-compare-conditional

This diagnostic is enabled by default.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types is deprecated

-Wdeprecated-enum-enum-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types is deprecated

-Wdeprecated-enum-float-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 

floating-point

enumeration

 type C 

with

from

and

 

enumeration

floating-point

 type D is deprecated

-Wdeprecated-implementations

Diagnostic text:

warning: implementing deprecated 

method

class

category

warning: implementing unavailable method

-Wdeprecated-increment-bool

This diagnostic is enabled by default.

Diagnostic text:

warning: incrementing expression of type bool is deprecated and incompatible with C++17

-Wdeprecated-objc-isa-usage

This diagnostic is enabled by default.

Diagnostic text:

warning: assignment to Objective-C’s isa is deprecated in favor of object_setClass()

warning: direct access to Objective-C’s isa is deprecated in favor of object_getClass()

-Wdeprecated-objc-pointer-introspection

This diagnostic is enabled by default.

Also controls -Wdeprecated-objc-pointer-introspection-performSelector.

Diagnostic text:

warning: bitmasking for introspection of Objective-C object pointers is strongly discouraged

-Wdeprecated-objc-pointer-introspection-performSelector

This diagnostic is enabled by default.

Diagnostic text:

warning: bitmasking for introspection of Objective-C object pointers is strongly discouraged

-Wdeprecated-register

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘register’ storage class specifier is deprecated and incompatible with C++17

-Wdeprecated-this-capture

Diagnostic text:

warning: implicit capture of ‘this’ with a capture default of ‘=’ is deprecated

-Wdeprecated-volatile

This diagnostic is enabled by default.

Diagnostic text:

warning: compound assignment to object of volatile-qualified type A is deprecated

warning: 

decrement

increment

 of object of volatile-qualified type B is deprecated

warning: use of result of assignment to object of volatile-qualified type A is deprecated

warning: volatile-qualified parameter type A is deprecated

warning: volatile-qualified return type A is deprecated

warning: volatile qualifier in structured binding declaration is deprecated

-Wdirect-ivar-access

Diagnostic text:

warning: instance variable A is being directly accessed

-Wdisabled-macro-expansion

Diagnostic text:

warning: disabled expansion of recursive macro

-Wdisabled-optimization

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wdiscard-qual

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wdistributed-object-modifiers

This diagnostic is enabled by default.

Diagnostic text:

warning: conflicting distributed object modifiers on parameter type in implementation of A

warning: conflicting distributed object modifiers on return type in implementation of A

-Wdivision-by-zero

This diagnostic is enabled by default.

Diagnostic text:

warning: 

remainder

division

 by zero is undefined

-Wdll-attribute-on-redeclaration

This diagnostic is enabled by default.

Diagnostic text:

warning: redeclaration of A should not add B attribute

-Wdllexport-explicit-instantiation-decl

This diagnostic is enabled by default.

Diagnostic text:

warning: explicit instantiation declaration should not be ‘dllexport’

-Wdllimport-static-field-def

This diagnostic is enabled by default.

Diagnostic text:

warning: definition of dllimport static field

-Wdocumentation

Also controls -Wdocumentation-deprecated-sync, -Wdocumentation-html.

Diagnostic text:

warning: 

\

@

class

interface

protocol

struct

union

‘ command should not be used in a comment attached to a non-

class

interface

protocol

struct

union

 declaration

warning: duplicated command ‘

\

@

B

warning: empty paragraph passed to ‘

\

@

B’ command

warning: 

\

@

classdesign

coclass

dependency

helper

helperclass

helps

instancesize

ownership

performance

security

superclass

‘ command should not be used in a comment attached to a non-container declaration

warning: 

\

@

function

functiongroup

method

methodgroup

callback

‘ command should be used in a comment attached to 

a function

a function

an Objective-C method

an Objective-C method

a pointer to function

 declaration

warning: HTML start tag prematurely ended, expected attribute name or ‘>’

warning: expected quoted string after equals sign

warning: 

\

@

B’ command does not have a valid word argument

warning: parameter ‘A’ is already documented

warning: unrecognized parameter passing direction, valid directions are ‘[in]’, ‘[out]’ and ‘[in,out]’

warning: 

\

@

param’ command used in a comment that is not attached to a function declaration

warning: parameter ‘A’ not found in the function declaration

warning: 

\

@

B’ command used in a comment that is attached to a 

function returning void

constructor

destructor

method returning void

warning: 

\

@

B’ command used in a comment that is not attached to a function or method declaration

warning: template parameter ‘A’ is already documented

warning: 

\

@

tparam’ command used in a comment that is not attached to a template declaration

warning: template parameter ‘A’ not found in the template declaration

warning: not a Doxygen trailing comment

warning: 

\

@

B’ command does not terminate a verbatim text block

-Wdocumentation-deprecated-sync

Diagnostic text:

warning: declaration is marked with ‘

\

@

deprecated’ command but does not have a deprecation attribute

-Wdocumentation-html

Diagnostic text:

warning: HTML end tag ‘A’ is forbidden

warning: HTML end tag does not match any start tag

warning: HTML tag ‘A’ requires an end tag

warning: HTML start tag ‘A’ closed by ‘B

-Wdocumentation-pedantic

Also controls -Wdocumentation-unknown-command.

Diagnostic text:

warning: whitespace is not allowed in parameter passing direction

-Wdocumentation-unknown-command

Diagnostic text:

warning: unknown command tag name ‘A’; did you mean ‘B’?

warning: unknown command tag name

-Wdollar-in-identifier-extension

Diagnostic text:

warning: ’$’ in identifier

-Wdouble-promotion

Diagnostic text:

warning: implicit conversion increases floating-point precision: A to B

-Wduplicate-decl-specifier

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: duplicate ‘A’ declaration specifier

warning: duplicate ‘A’ declaration specifier

warning: multiple identical address spaces specified for type

warning: duplicate ‘A’ declaration specifier

-Wduplicate-enum

Diagnostic text:

warning: element A has been implicitly assigned B which another element has been assigned

-Wduplicate-method-arg

Diagnostic text:

warning: redeclaration of method parameter A

-Wduplicate-method-match

Diagnostic text:

warning: multiple declarations of method A found and ignored

-Wduplicate-protocol

This diagnostic is enabled by default.

Diagnostic text:

warning: duplicate protocol definition of A is ignored

-Wdynamic-class-memaccess

This diagnostic is enabled by default.

Diagnostic text:

warning: 

destination for

source of

first operand of

second operand of

 this B call is a pointer to 

class containing a 

dynamic class D; vtable pointer will be 

overwritten

copied

moved

compared

-Wdynamic-exception-spec

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-dynamic-exception-spec.

Diagnostic text:

error: ISO C++17 does not allow dynamic exception specifications

-Wembedded-directive

Diagnostic text:

warning: embedding a directive within macro arguments has undefined behavior

-Wempty-body

This diagnostic is enabled by default.

Diagnostic text:

warning: for loop has empty body

warning: if statement has empty body

warning: range-based for loop has empty body

warning: switch statement has empty body

warning: while loop has empty body

-Wempty-decomposition

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++17 does not allow a decomposition group to be empty

-Wempty-init-stmt

Diagnostic text:

warning: empty initialization statement of ‘

if

switch

range-based for

‘ has no effect

-Wempty-translation-unit

Diagnostic text:

warning: ISO C requires a translation unit to contain at least one declaration

-Wencode-type

This diagnostic is enabled by default.

Diagnostic text:

warning: encoding of A type is incomplete because B component has unknown encoding

-Wenum-compare

This diagnostic is enabled by default.

Also controls -Wdeprecated-enum-compare, -Wenum-compare-switch.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types

-Wenum-compare-conditional

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-enum-compare-conditional.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types

-Wenum-compare-switch

This diagnostic is enabled by default.

Diagnostic text:

warning: comparison of different enumeration types in switch statement

-Wenum-conversion

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wenum-compare-conditional, -Wenum-enum-conversion, -Wenum-float-conversion.

Diagnostic text:

warning: implicit conversion from enumeration type A to different enumeration type B

-Wenum-enum-conversion

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-enum-enum-conversion.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 different enumeration types

-Wenum-float-conversion

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-enum-float-conversion.

Diagnostic text:

warning: 

arithmetic between

bitwise operation between

comparison of

conditional expression between

compound assignment of

 

floating-point

enumeration

 type C 

with

from

and

 

enumeration

floating-point

 type D

-Wenum-too-large

This diagnostic is enabled by default.

Diagnostic text:

warning: enumeration values exceed range of largest integer

warning: incremented enumerator value A is not representable in the largest integer type

-Wexceptions

This diagnostic is enabled by default.

Diagnostic text:

warning: cannot refer to a non-static member from the handler of a 

constructor

destructor

 function try block

warning: exception of type A will be caught by earlier handler

warning: A has a non-throwing exception specification but can still throw

-Wexit-time-destructors

Diagnostic text:

warning: declaration requires an exit-time destructor

-Wexpansion-to-defined

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: macro expansion producing ‘defined’ has undefined behavior

warning: macro expansion producing ‘defined’ has undefined behavior

-Wexperimental-isel

This diagnostic is enabled by default.

Diagnostic text:

warning: -fexperimental-isel support for the ‘A’ architecture is incomplete

warning: -fexperimental-isel support is incomplete for this architecture at the current optimization level

-Wexplicit-initialize-call

This diagnostic is enabled by default.

Diagnostic text:

warning: explicit call to +initialize results in duplicate call to +initialize

warning: explicit call to [super initialize] should only be in implementation of +initialize

-Wexplicit-ownership-type

Diagnostic text:

warning: method parameter of type A with no explicit ownership

-Wexport-unnamed

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++20 does not permit 

an empty

a static_assert

 declaration to appear in an export block

warning: ISO C++20 does not permit a declaration that does not introduce any names to be exported

-Wexport-using-directive

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++20 does not permit using directive to be exported

-Wextern-c-compat

This diagnostic is enabled by default.

Diagnostic text:

warning: 

empty 

struct

union

 has size 0 in C, 

size 1

non-zero size

 in C++

-Wextern-initializer

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘extern’ variable has an initializer

-Wextra

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wdeprecated-copy, -Wempty-init-stmt, -Wignored-qualifiers, -Winitializer-overrides, -Wmissing-field-initializers, -Wmissing-method-return-type, -Wnull-pointer-arithmetic, -Wsemicolon-before-method-body, -Wsign-compare, -Wunused-parameter.

Diagnostic text:

warning: call to function without interrupt attribute could clobber interruptee’s VFP registers

-Wextra-qualification

This diagnostic is enabled by default.

Diagnostic text:

warning: extra qualification on member A

-Wextra-semi

Also controls -Wc++11-extra-semi, -Wc++98-compat-extra-semi.

Diagnostic text:

warning: extra ‘;’ 

outside of a function

inside a B

inside instance variable list

after member function definition

warning: extra ‘;’ after member function definition

-Wextra-semi-stmt

Also controls -Wempty-init-stmt.

Diagnostic text:

warning: empty expression statement has no effect; remove unnecessary ‘;’ to silence this warning

-Wextra-tokens

This diagnostic is enabled by default.

Diagnostic text:

warning: extra tokens at end of #A directive

warning: extra tokens at the end of ‘#pragma omp A’ are ignored

-Wfallback

This diagnostic is enabled by default.

Diagnostic text:

warning: falling back to A

-Wfinal-dtor-non-final-class

This diagnostic is enabled by default.

Diagnostic text:

warning: class with destructor marked ‘

final

sealed

‘ cannot be inherited from

-Wfixed-enum-extension

Diagnostic text:

warning: enumeration types with a fixed underlying type are a Clang extension

-Wflag-enum

This diagnostic is enabled by default.

Diagnostic text:

warning: enumeration value A is out of range of flags in enumeration type B

-Wflexible-array-extensions

Diagnostic text:

warning: A may not be used as an array element due to flexible array member

warning: A may not be nested in a struct due to flexible array member

-Wfloat-conversion

Also controls -Wfloat-overflow-conversion, -Wfloat-zero-conversion.

Diagnostic text:

warning: implicit conversion turns floating-point number into integer: A to B

-Wfloat-equal

Diagnostic text:

warning: comparing floating point with == or != is unsafe

-Wfloat-overflow-conversion

Diagnostic text:

warning: implicit conversion from A to B changes value from C to D

warning: implicit conversion of out of range value from A to B is undefined

-Wfloat-zero-conversion

Diagnostic text:

warning: implicit conversion from A to B changes non-zero value from C to D

-Wfor-loop-analysis

Diagnostic text:

warning: variable A is 

decremented

incremented

 both in the loop header and in the loop body

warning: variable

s

 B

s B and C

s B, C, and D

s B, C, D, and E

 used in loop condition not modified in loop body

-Wformat

This diagnostic is enabled by default.

Also controls -Wformat-extra-args, -Wformat-invalid-specifier, -Wformat-security, -Wformat-y2k, -Wformat-zero-length, -Wnonnull.

Diagnostic text:

warning: using ‘%%P’ format specifier without precision

warning: 

values of type

enum values with underlying type

 A’ should not be used as format arguments; add an explicit cast to B instead

warning: using ‘A’ format specifier, but argument has boolean value

warning: format specifies type A but the argument has 

type

underlying type

 B

warning: using ‘A’ format specifier annotation outside of os_log()/os_trace()

warning: invalid position specified for 

field width

field precision

warning: cannot mix positional and non-positional arguments in format string

warning: length modifier ‘A’ results in undefined behavior or no effect with ‘B’ conversion specifier

warning: format string should not be a wide string

warning: position arguments in format strings start counting at 1 (not 0)

warning: format string missing

warning: object format flags cannot be used with ‘A’ conversion specifier

warning: 

*

.*

‘ specified field 

width

precision

 is missing a matching ‘int’ argument

warning: field 

width

precision

 should have type B, but argument has type C

warning: missing object format flag

warning: format string contains ‘\0’ within the string body

warning: format string is not null-terminated

warning: flag ‘A’ is ignored when flag ‘B’ is present

warning: incomplete format specifier

warning: more ‘%%’ conversions than data arguments

warning: A’ is not a valid object format flag

warning: flag ‘A’ results in undefined behavior with ‘B’ conversion specifier

warning: 

field width

precision

 used with ‘B’ conversion specifier, resulting in undefined behavior

warning: data argument position ‘A’ exceeds the number of data arguments (B)

warning: zero field width in scanf format string is unused

warning: no closing ‘]’ for ‘%%[‘ in scanf format string

-Wformat-extra-args

This diagnostic is enabled by default.

Diagnostic text:

warning: data argument not used by format string

-Wformat-invalid-specifier

This diagnostic is enabled by default.

Diagnostic text:

warning: invalid conversion specifier ‘A

-Wformat-non-iso

Diagnostic text:

warning: A 

length modifier

conversion specifier

 is not supported by ISO C

warning: using length modifier ‘A’ with conversion specifier ‘B’ is not supported by ISO C

warning: positional arguments are not supported by ISO C

-Wformat-nonliteral

Diagnostic text:

warning: format string is not a string literal

-Wformat-pedantic

Diagnostic text:

warning: 

values of type

enum values with underlying type

 A’ should not be used as format arguments; add an explicit cast to B instead

warning: format specifies type A but the argument has 

type

underlying type

 B

-Wformat-security

This diagnostic is enabled by default.

Diagnostic text:

warning: format string is not a string literal (potentially insecure)

-Wformat-type-confusion

Diagnostic text:

warning: format specifies type A but the argument has 

type

underlying type

 B

-Wformat-y2k

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wformat-zero-length

This diagnostic is enabled by default.

Diagnostic text:

warning: format string is empty

-Wformat=2

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wformat-nonliteral, -Wformat-security, -Wformat-y2k.

-Wfortify-source

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ will always overflow; destination buffer has size B, but size argument is C

warning: A’ size argument is too large; destination buffer has size B, but size argument is C

-Wfour-char-constants

Diagnostic text:

warning: multi-character character constant

-Wframe-larger-than=

This diagnostic is enabled by default.

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

warning: stack frame size of A bytes in B

-Wframework-include-private-from-public

This diagnostic is enabled by default.

Diagnostic text:

warning: public framework header includes private framework header ‘A

-Wfunction-def-in-objc-container

This diagnostic is enabled by default.

Diagnostic text:

warning: function definition inside an Objective-C container is deprecated

-Wfunction-multiversion

This diagnostic is enabled by default.

Diagnostic text:

warning: body of cpu_dispatch function will be ignored

warning: CPU list contains duplicate entries; attribute ignored

-Wfuture-compat

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wgcc-compat

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: ‘diagnose_if’ is a clang extension

warning: ‘enable_if’ is a clang extension

warning: __final is a GNU extension, consider using C++11 final

warning: GCC does not allow A attribute in this position on a function definition

warning: ‘break’ is bound to loop, GCC binds it to switch

warning: GCC does not allow the ‘cleanup’ attribute argument to be anything other than a simple identifier

warning: GCC does not allow an attribute in this position on a function declaration

warning: GCC does not allow the A attribute to be written on a type

warning: GCC does not allow variable declarations in for loop initializers before C99

warning: A’ is bound to current loop, GCC binds it to the enclosing loop

-Wglobal-constructors

Diagnostic text:

warning: declaration requires a global constructor

warning: declaration requires a global destructor

-Wgnu-alignof-expression

This diagnostic is enabled by default.

Diagnostic text:

warning: A applied to an expression is a GNU extension

-Wgnu-anonymous-struct

Diagnostic text:

warning: anonymous structs are a GNU extension

-Wgnu-array-member-paren-init

This diagnostic is an error by default, but the flag -Wno-gnu-array-member-paren-init can be used to disable the error.

Diagnostic text:

error: parenthesized initialization of a member array is a GNU extension

-Wgnu-auto-type

Diagnostic text:

warning: ’__auto_type’ is a GNU extension

-Wgnu-binary-literal

Diagnostic text:

warning: binary integer literals are a GNU extension

-Wgnu-case-range

Diagnostic text:

warning: use of GNU case range extension

-Wgnu-complex-integer

Diagnostic text:

warning: complex integer types are a GNU extension

-Wgnu-compound-literal-initializer

Diagnostic text:

warning: initialization of an array from a compound literal is a GNU extension

-Wgnu-conditional-omitted-operand

Diagnostic text:

warning: use of GNU ?: conditional expression extension, omitting middle operand

-Wgnu-designator

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: use of GNU array range extension

warning: use of GNU ‘missing =’ extension in designator

warning: use of GNU old-style field designator extension

-Wgnu-empty-initializer

Diagnostic text:

warning: use of GNU empty initializer extension

-Wgnu-empty-struct

Diagnostic text:

warning: empty 

struct

union

 is a GNU extension

warning: flexible array member A in otherwise empty 

struct

interface

union

class

enum

 is a GNU extension

warning: 

struct

union

 without named members is a GNU extension

-Wgnu-flexible-array-initializer

Diagnostic text:

warning: flexible array initialization is a GNU extension

-Wgnu-flexible-array-union-member

Diagnostic text:

warning: flexible array member A in a union is a GNU extension

-Wgnu-folding-constant

Diagnostic text:

warning: expression is not an 

integer

integral

 constant expression; folding it to a constant is a GNU extension

warning: in-class initializer for static data member is not a constant expression; folding it to a constant is a GNU extension

warning: variable length array folded to constant array as an extension

-Wgnu-imaginary-constant

Diagnostic text:

warning: imaginary constants are a GNU extension

-Wgnu-include-next

Diagnostic text:

warning: #include_next is a language extension

-Wgnu-inline-cpp-without-extern

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘gnu_inline’ attribute without ‘extern’ in C++ treated as externally available, this changed in Clang 10

-Wgnu-label-as-value

Diagnostic text:

warning: use of GNU address-of-label extension

warning: use of GNU indirect-goto extension

-Wgnu-redeclared-enum

Diagnostic text:

warning: redeclaration of already-defined enum A is a GNU extension

-Wgnu-statement-expression

Diagnostic text:

warning: use of GNU statement expression extension

-Wgnu-static-float-init

This diagnostic is enabled by default.

Diagnostic text:

warning: in-class initializer for static data member of type A is a GNU extension

-Wgnu-string-literal-operator-template

This diagnostic is enabled by default.

Diagnostic text:

warning: string literal operator templates are a GNU extension

-Wgnu-union-cast

Diagnostic text:

warning: cast to union type is a GNU extension

-Wgnu-variable-sized-type-not-at-end

This diagnostic is enabled by default.

Diagnostic text:

warning: field A with variable sized type B not at the end of a struct or class is a GNU extension

-Wgnu-zero-line-directive

Diagnostic text:

warning: #line directive with zero argument is a GNU extension

-Wgnu-zero-variadic-macro-arguments

Diagnostic text:

warning: must specify at least one argument for ‘…’ parameter of variadic macro

warning: token pasting of ‘,’ and __VA_ARGS__ is a GNU extension

-Wheader-guard

This diagnostic is enabled by default.

Diagnostic text:

warning: A is used as a header guard here, followed by #define of a different macro

-Wheader-hygiene

Diagnostic text:

warning: using namespace directive in global context in header

-Whip-only

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ is ignored since it is only supported for HIP

-Widiomatic-parentheses

Diagnostic text:

warning: using the result of an assignment as a condition without parentheses

-Wignored-attributes

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘trivial_abi’ cannot be applied to A

warning: 

alias

ifunc

 will always resolve to A even if weak definition of B is overridden

warning: 

alias

ifunc

 will not be in section ‘A’ but in the same section as the 

aliasee

resolver

warning: ‘abi_tag’ attribute on 

non-inline

anonymous

 namespace ignored

warning: attribute A after definition is ignored

warning: ‘dllexport’ attribute ignored on explicit instantiation definition

warning: A attribute can only be applied to instance variables or properties

warning: A attribute ignored

warning: A attribute ignored for field of type B

warning: A attribute ignored on inline function

warning: A’ attribute cannot be specified on a definition

warning: attribute A ignored, because it is not attached to a declaration

warning: ‘nonnull’ attribute applied to function with no pointer arguments

warning: ‘nonnull’ attribute when used on parameters takes no arguments

warning: A attribute ignored when parsing type

warning: A attribute only applies to a pointer or reference (B is invalid)

warning: A attribute only applies to

 constant

 pointer arguments

warning: attribute declaration must precede definition

warning: A attribute only applies to return values that are pointers

warning: A attribute only applies to return values that are pointers or references

warning: ‘sentinel’ attribute requires named arguments

warning: ‘sentinel’ attribute only supported for variadic 

functions

blocks

warning: A attribute argument not supported: B

warning: unknown visibility A

warning: attribute A cannot be applied to 

functions

Objective-C method

 without return value

warning: __weak attribute cannot be specified on a field declaration

warning: __weak attribute cannot be specified on an automatic variable when ARC is not enabled

warning: A attribute only applies to 

functions

unions

variables and functions

functions and methods

functions, methods and blocks

functions, methods, and parameters

variables

variables and fields

variables, data members and tag types

types and namespaces

variables, functions and classes

kernel functions

non-K&R-style functions

warning: A attribute only applies to B

warning: attribute A ignored, because it cannot be applied to omitted return type

warning: A calling convention is not supported 

for this target

on variadic function

on constructor/destructor

on builtin function

warning: attribute A ignored, because it cannot be applied to a type

warning: ignoring __declspec(allocator) because the function return type A is not a pointer or reference type

warning: attribute A is ignored, place it after “

class

struct

interface

union

enum

” to apply attribute to type declaration

warning: ‘deprecated’ attribute on anonymous namespace ignored

warning: A redeclared inline; B attribute ignored

warning: attribute A is already applied with different parameters

warning: attribute A is already applied

warning: Objective-C GC does not allow weak variables on the stack

warning: ‘gnu_inline’ attribute requires function to be marked ‘inline’, attribute ignored

warning: inheritance model ignored on 

primary template

partial specialization

warning: ‘objc_externally_retained’ can only be applied to local variables 

of retainable type

with strong ownership

warning: ‘internal_linkage’ attribute on a non-static local variable is ignored

warning: 

MIPS

MSP430

RISC-V

 ‘interrupt’ attribute only applies to functions that have 

no parameters

a ‘void’ return type

warning: qualifiers after comma in declarator list are ignored

warning: ‘mig_server_routine’ attribute only applies to routines that return a kern_return_t

warning: unknown attribute ‘A

warning: ‘nocf_check’ attribute ignored; use -fcf-protection to enable the attribute

warning: ‘noderef’ can only be used on an array or pointer type

warning: ‘nothrow’ attribute conflicts with exception specification; attribute ignored

warning: A attribute only applies to 

Objective-C object

pointer

pointer-to-CF-pointer

pointer/reference-to-OSObject-pointer

 parameters

warning: A attribute only applies to 

functions

methods

properties

 that return 

an Objective-C object

a pointer

a non-retainable pointer

warning: A attribute isn’t implemented by this Objective-C runtime

warning: direct attribute on property A ignored (not implemented by this Objective-C runtime)

warning: A attribute is deprecated and ignored in OpenCL version B

warning: ‘require_constant_initialization’ attribute added after initialization of variable

warning: repeated RISC-V ‘interrupt’ attribute

warning: template parameter of a function template with the ‘sycl_kernel’ attribute cannot be a non-type template parameter

warning: function template with ‘sycl_kernel’ attribute must have a single parameter

warning: ‘sycl_kernel’ attribute only applies to a function template with at least two template parameters

warning: function template with ‘sycl_kernel’ attribute must have a ‘void’ return type

warning: 

alignment

size

 of field B (C bits) does not match the 

alignment

size

 of the first field in transparent union; transparent_union attribute ignored

warning: first field of a transparent union cannot have 

floating point

vector

 type B; transparent_union attribute ignored

warning: transparent_union attribute can only be applied to a union definition; attribute ignored

warning: transparent union definition must contain at least one field; transparent_union attribute ignored

warning: A’ only applies to 

function

pointer

Objective-C object or block pointer

 types; type here is C

warning: __declspec attribute A is not supported

warning: 

unsupported

duplicate

 architecture

 C’ in the ‘target’ attribute string; ‘target’ attribute ignored

warning: ’__clang__’ is a predefined macro name, not an attribute scope specifier; did you mean ‘_Clang’ instead?

-Wignored-optimization-argument

This diagnostic is enabled by default.

Diagnostic text:

warning: optimization flag ‘A’ is not supported for target ‘B

warning: optimization flag ‘A’ is not supported

-Wignored-pragma-intrinsic

This diagnostic is enabled by default.

Diagnostic text:

warning: A is not a recognized builtin

; consider including <intrin.h> to access non-builtin intrinsics

-Wignored-pragma-optimize

This diagnostic is enabled by default.

Diagnostic text:

warning: ’#pragma optimize’ is not supported

-Wignored-pragmas

This diagnostic is enabled by default.

Also controls -Wignored-pragma-intrinsic, -Wignored-pragma-optimize.

Diagnostic text:

warning: expected ‘=’ following ‘#pragma 

align

options align

‘ - ignored

warning: invalid alignment option in ‘#pragma 

align

options align

‘ - ignored

warning: OpenCL extension end directive mismatches begin directive - ignoring

warning: ’#pragma comment A’ ignored

warning: missing argument to debug command ‘A

warning: unexpected debug command ‘A

warning: unknown module ‘A

warning: expected action or ‘)’ in ‘#pragma A’ - ignored

warning: missing ‘:’ after A - ignoring

warning: missing ‘:’ or ‘)’ after A - ignoring

warning: expected ‘,’ in ‘#pragma A

warning: expected identifier in ‘#pragma A’ - ignored

warning: expected ‘compiler’, ‘lib’, ‘user’, or a string literal for the section name in ‘#pragma A’ - ignored

warning: expected integer between A and B inclusive in ‘#pragma C’ - ignored

warning: missing ‘(‘ after ‘#pragma A’ - ignoring

warning: expected non-wide string literal in ‘#pragma A

warning: expected 

‘enable’, ‘disable’, ‘begin’ or ‘end’

‘disable’

 - ignoring

warning: expected ‘)’ or ‘,’ in ‘#pragma A

warning: missing ‘)’ after ‘#pragma A’ - ignoring

warning: expected a stack label or a string literal for the section name in ‘#pragma A’ - ignored

warning: expected a string literal for the section name in ‘#pragma A’ - ignored

warning: expected push, pop or a string literal for the section name in ‘#pragma A’ - ignored

warning: expected string literal in ‘#pragma A’ - ignoring

warning: extra tokens at end of ‘#pragma A’ - ignored

warning: incorrect use of #pragma clang force_cuda_host_device begin|end

warning: ’#pragma init_seg’ is only supported when targeting a Microsoft environment

warning: unknown action for ‘#pragma A’ - ignored

warning: unexpected argument ‘A’ to ‘#pragma B

; expected D

warning: unknown action ‘B’ for ‘#pragma A’ - ignored

warning: missing argument to ‘#pragma A

; expected C

warning: incorrect use of ‘#pragma ms_struct on|off’ - ignored

warning: #pragma options align=reset failed: A

warning: expected ‘align’ following ‘#pragma options’ - ignored

warning: expected #pragma pack parameter to be ‘1’, ‘2’, ‘4’, ‘8’, or ‘16’

warning: expected integer or identifier in ‘#pragma pack’ - ignored

warning: #pragma A(pop, …) failed: B

warning: pragma pop_macro could not pop ‘A’, no matching push_macro

warning: unknown OpenCL extension A - ignoring

warning: known but unsupported action ‘B’ for ‘#pragma A’ - ignored

warning: unsupported OpenCL extension A - ignoring

warning: expected ‘#pragma unused’ argument to be a variable name

warning: only variables can be arguments to ‘#pragma unused’

warning: undeclared variable A used as an argument for ‘#pragma unused’

-Wignored-qualifiers

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: ARC 

unused

__unsafe_unretained

__strong

__weak

__autoreleasing

 lifetime qualifier on return type is ignored

warning: A’ qualifier on omitted return type B has no effect

warning: A’ type qualifier

s

 on return type 

has

have

 no effect

warning: A’ qualifier on function type B has no effect

warning: A’ qualifier on reference type B has no effect

-Wimplicit

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wimplicit-function-declaration, -Wimplicit-int.

-Wimplicit-atomic-properties

Diagnostic text:

warning: property is assumed atomic when auto-synthesizing the property

warning: property is assumed atomic by default

-Wimplicit-conversion-floating-point-to-bool

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit conversion turns floating-point number into bool: A to B

-Wimplicit-exception-spec-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: function previously declared with an 

explicit

implicit

 exception specification redeclared with an 

implicit

explicit

 exception specification

-Wimplicit-fallthrough

Also controls -Wimplicit-fallthrough-per-function.

Diagnostic text:

warning: fallthrough annotation in unreachable code

warning: unannotated fall-through between switch labels

-Wimplicit-fallthrough-per-function

Diagnostic text:

warning: unannotated fall-through between switch labels in partly-annotated function

-Wimplicit-fixed-point-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit conversion from A cannot fit within the range of values for B

-Wimplicit-float-conversion

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wimplicit-int-float-conversion, -Wobjc-signed-char-bool-implicit-float-conversion.

Diagnostic text:

warning: implicit conversion loses floating-point precision: A to B

warning: implicit conversion when assigning computation result loses floating-point precision: A to B

-Wimplicit-function-declaration

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: implicit declaration of function A is invalid in C99

warning: implicitly declaring library function ‘A’ with type B

error: use of unknown builtin A

warning: implicit declaration of function A

-Wimplicit-int

This diagnostic is enabled by default.

Diagnostic text:

warning: type specifier missing, defaults to ‘int’

-Wimplicit-int-conversion

Also controls -Wobjc-signed-char-bool-implicit-int-conversion.

Diagnostic text:

warning: higher order bits are zeroes after implicit conversion

warning: implicit conversion loses integer precision: A to B

-Wimplicit-int-float-conversion

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: implicit conversion from A to B may lose precision

warning: implicit conversion from C to D changes value from A to B

-Wimplicit-retain-self

Diagnostic text:

warning: block implicitly retains ‘self’; explicitly mention ‘self’ to indicate this is intended behavior

-Wimplicitly-unsigned-literal

This diagnostic is enabled by default.

Diagnostic text:

warning: integer literal is too large to be represented in a signed integer type, interpreting as unsigned

-Wimport

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wimport-preprocessor-directive-pedantic

Diagnostic text:

warning: #import is a language extension

-Winaccessible-base

This diagnostic is enabled by default.

Diagnostic text:

warning: direct base A is inaccessible due to ambiguity:B

-Winclude-next-absolute-path

This diagnostic is enabled by default.

Diagnostic text:

warning: #include_next in file found relative to primary source file or found by absolute path; will search from start of include path

-Winclude-next-outside-header

This diagnostic is enabled by default.

Diagnostic text:

warning: #include_next in primary source file; will search from start of include path

-Wincompatible-exception-spec

This diagnostic is enabled by default.

Diagnostic text:

warning: exception specifications of 

return

argument

 types differ

warning: target exception specification is not superset of source

-Wincompatible-function-pointer-types

This diagnostic is enabled by default.

Diagnostic text:

warning: incompatible function pointer types 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

; dereference with *

; take the address with &

; remove *

; remove &

-Wincompatible-library-redeclaration

This diagnostic is enabled by default.

Diagnostic text:

warning: incompatible redeclaration of library function A

-Wincompatible-ms-struct

This diagnostic is an error by default, but the flag -Wno-incompatible-ms-struct can be used to disable the error.

Diagnostic text:

error: ms_struct may not produce Microsoft-compatible layouts for classes with base classes or virtual functions

error: ms_struct may not produce Microsoft-compatible layouts with fundamental data types with sizes that aren’t a power of two

-Wincompatible-pointer-types

This diagnostic is enabled by default.

Also controls -Wincompatible-function-pointer-types, -Wincompatible-pointer-types-discards-qualifiers.

Diagnostic text:

warning: incompatible pointer types 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

; dereference with *

; take the address with &

; remove *

; remove &

-Wincompatible-pointer-types-discards-qualifiers

This diagnostic is enabled by default.

Diagnostic text:

warning: 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

 discards qualifiers in nested pointer types

warning: 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

 discards qualifiers

warning: 

reinterpret_cast

C-style cast

 from B to C changes address space of nested pointers

-Wincompatible-property-type

This diagnostic is enabled by default.

Diagnostic text:

warning: property type A is incompatible with type B inherited from C

-Wincompatible-sysroot

This diagnostic is enabled by default.

Diagnostic text:

warning: using sysroot for ‘A’ but targeting ‘B

-Wincomplete-framework-module-declaration

This diagnostic is enabled by default.

Diagnostic text:

warning: skipping ‘A’ because module declaration of ‘B’ lacks the ‘framework’ qualifier

-Wincomplete-implementation

This diagnostic is enabled by default.

Diagnostic text:

warning: method definition for A not found

-Wincomplete-module

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wincomplete-umbrella, -Wnon-modular-include-in-module.

-Wincomplete-setjmp-declaration

This diagnostic is enabled by default.

Diagnostic text:

warning: declaration of built-in function ‘A’ requires the declaration of the ‘jmp_buf’ type, commonly provided in the header <setjmp.h>.

-Wincomplete-umbrella

This diagnostic is enabled by default.

Diagnostic text:

warning: missing submodule ‘A

warning: umbrella directory ‘A’ not found

warning: umbrella header for module ‘A’ does not include header ‘B

-Winconsistent-dllimport

This diagnostic is enabled by default.

Diagnostic text:

warning: A redeclared without B attribute: previous B ignored

warning: A redeclared without ‘dllimport’ attribute: ‘dllexport’ attribute added

-Winconsistent-missing-destructor-override

Diagnostic text:

warning: A overrides a destructor but is not marked ‘override’

-Winconsistent-missing-override

This diagnostic is enabled by default.

Diagnostic text:

warning: A overrides a member function but is not marked ‘override’

-Wincrement-bool

This diagnostic is enabled by default.

Also controls -Wdeprecated-increment-bool.

Diagnostic text:

error: ISO C++17 does not allow incrementing expression of type bool

-Winfinite-recursion

Diagnostic text:

warning: all paths through this function will call itself

-Winit-self

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Winitializer-overrides

This diagnostic is enabled by default.

Diagnostic text:

warning: initializer 

partially 

overrides prior initialization of this subobject

warning: initializer 

partially 

overrides prior initialization of this subobject

-Winjected-class-name

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++ specifies that qualified reference to A is a constructor name rather than a 

template name

type

 in this context, despite preceding 

‘typename’

‘template’

 keyword

-Winline

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Winline-asm

This diagnostic is enabled by default.

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-Winline-new-delete

This diagnostic is enabled by default.

Diagnostic text:

warning: replacement function A cannot be declared ‘inline’

-Winstantiation-after-specialization

This diagnostic is enabled by default.

Diagnostic text:

warning: explicit instantiation of A that occurs after an explicit specialization has no effect

-Wint-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: incompatible integer to pointer conversion 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

; dereference with *

; take the address with &

; remove *

; remove &

warning: incompatible pointer to integer conversion 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

; dereference with *

; take the address with &

; remove *

; remove &

-Wint-in-bool-context

Diagnostic text:

warning: converting the enum constant to a boolean

warning: converting the result of ‘<<’ to a boolean; did you mean ‘(A) != 0’?

-Wint-to-pointer-cast

This diagnostic is enabled by default.

Also controls -Wint-to-void-pointer-cast.

Diagnostic text:

warning: cast to B from smaller integer type A

-Wint-to-void-pointer-cast

This diagnostic is enabled by default.

Diagnostic text:

warning: cast to B from smaller integer type A

-Winteger-overflow

This diagnostic is enabled by default.

Diagnostic text:

warning: overflow in expression; result is A with type B

-Winvalid-command-line-argument

This diagnostic is enabled by default.

Also controls -Wignored-optimization-argument.

Diagnostic text:

warning: the given MCU supports A hardware multiply, but -mhwmult is set to B.

warning: no MCU device specified, but ‘-mhwmult’ is set to ‘auto’, assuming no hardware multiply. Use -mmcu to specify a MSP430 device, or -mhwmult to set hardware multiply type explicitly.

warning: the given MCU does not support hardware multiply, but -mhwmult is set to A.

warning: the object size sanitizer has no effect at -O0, but is explicitly enabled: A

warning: optimization level ‘A’ is not supported; using ‘BC’ instead

warning: ignoring extension ‘A’ because the ‘B’ architecture does not support it

-Winvalid-constexpr

This diagnostic is an error by default, but the flag -Wno-invalid-constexpr can be used to disable the error.

Diagnostic text:

error: constexpr 

function

constructor

 never produces a constant expression

-Winvalid-iboutlet

This diagnostic is enabled by default.

Diagnostic text:

warning: 

instance variable

property

 with A attribute must be an object type (invalid B)

warning: IBOutletCollection properties should be copy/strong and not assign

-Winvalid-initializer-from-system-header

This diagnostic is enabled by default.

Diagnostic text:

warning: invalid constructor form class in system header, should not be explicit

-Winvalid-ios-deployment-target

This diagnostic is an error by default, but the flag -Wno-invalid-ios-deployment-target can be used to disable the error.

Diagnostic text:

error: invalid iOS deployment version ‘A’, iOS 10 is the maximum deployment target for 32-bit targets

-Winvalid-no-builtin-names

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ is not a valid builtin name for B

-Winvalid-noreturn

This diagnostic is enabled by default.

Diagnostic text:

warning: function declared ‘noreturn’ should not return

warning: function A declared ‘noreturn’ should not return

-Winvalid-offsetof

This diagnostic is enabled by default.

Diagnostic text:

warning: offset of on non-POD type A

warning: offset of on non-standard-layout type A

-Winvalid-or-nonexistent-directory

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: environment variable SCE_ORBIS_SDK_DIR is set, but points to invalid or nonexistent directory ‘A

warning: unable to find A directory, expected to be in ‘B

-Winvalid-partial-specialization

This diagnostic is an error by default, but the flag -Wno-invalid-partial-specialization can be used to disable the error.

Diagnostic text:

error: 

class

variable

 template partial specialization is not more specialized than the primary template

-Winvalid-pch

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Winvalid-pp-token

This diagnostic is enabled by default.

Diagnostic text:

warning: empty character constant

warning: missing terminating 

‘”’

 character

-Winvalid-source-encoding

This diagnostic is enabled by default.

Diagnostic text:

warning: illegal character encoding in character literal

warning: illegal character encoding in string literal

-Winvalid-token-paste

This diagnostic is an error by default, but the flag -Wno-invalid-token-paste can be used to disable the error.

Diagnostic text:

error: pasting formed ‘A’, an invalid preprocessing token

-Wjump-seh-finally

This diagnostic is enabled by default.

Diagnostic text:

warning: jump out of __finally block has undefined behavior

-Wkeyword-compat

This diagnostic is enabled by default.

Diagnostic text:

warning: keyword ‘A’ will be made available as an identifier 

here

for the remainder of the translation unit

-Wkeyword-macro

Diagnostic text:

warning: keyword is hidden by macro definition

-Wknr-promoted-parameter

This diagnostic is enabled by default.

Diagnostic text:

warning: promoted type of K&R function parameter is not compatible with parameter type declared in a previous prototype

-Wlanguage-extension-token

Diagnostic text:

warning: extension used

-Wlarge-by-value-copy

This diagnostic is enabled by default.

Diagnostic text:

warning: A is a large (B bytes) pass-by-value argument; pass it by reference instead ?

warning: return value of A is a large (B bytes) pass-by-value object; pass it by reference instead ?

-Wliblto

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wliteral-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit conversion from A to B changes value from C to D

warning: implicit conversion of out of range value from A to B is undefined

-Wliteral-range

This diagnostic is enabled by default.

Diagnostic text:

warning: magnitude of floating-point constant too large for type A; maximum is B

warning: magnitude of floating-point constant too small for type A; minimum is B

-Wlocal-type-template-args

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++98-compat-local-type-template-args.

Diagnostic text:

warning: template argument uses local type A

-Wlogical-not-parentheses

This diagnostic is enabled by default.

Diagnostic text:

warning: logical not is only applied to the left hand side of this 

comparison

bitwise operator

-Wlogical-op-parentheses

Diagnostic text:

warning: ’&&’ within ‘||’

-Wlong-long

Also controls -Wc++11-long-long.

Diagnostic text:

warning: ‘long long’ is an extension when C99 mode is not enabled

-Wmacro-redefined

This diagnostic is enabled by default.

Diagnostic text:

warning: A macro redefined

-Wmain

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: ISO C++ does not allow ‘main’ to be used by a program

warning: ‘main’ is not allowed to be declared _Noreturn

warning: ‘main’ is not allowed to be declared variadic

warning: only one parameter on ‘main’ declaration

warning: variable named ‘main’ with external linkage has undefined behavior

warning: bool literal returned from ‘main’

warning: ‘main’ should not be declared static

-Wmain-return-type

This diagnostic is enabled by default.

Diagnostic text:

warning: return type of ‘main’ is not ‘int’

-Wmalformed-warning-check

This diagnostic is enabled by default.

Diagnostic text:

warning: __has_warning expected option name (e.g. “-Wundef”)

-Wmany-braces-around-scalar-init

This diagnostic is enabled by default.

Diagnostic text:

warning: too many braces around scalar initializer

-Wmax-unsigned-zero

This diagnostic is enabled by default.

Diagnostic text:

warning: taking the max of 

a value and unsigned zero

unsigned zero and a value

 is always equal to the other value

-Wmemset-transposed-args

This diagnostic is enabled by default.

Diagnostic text:

warning: 

‘size’ argument to memset is ‘0’

setting buffer to a ‘sizeof’ expression

; did you mean to transpose the last two arguments?

-Wmemsize-comparison

This diagnostic is enabled by default.

Diagnostic text:

warning: size argument in A call is a comparison

-Wmethod-signatures

Diagnostic text:

warning: conflicting parameter types in implementation of A: B vs C

warning: conflicting return type in implementation of A: B vs C

-Wmicrosoft-anon-tag

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: types declared in an anonymous 

struct

union

 are a Microsoft extension

warning: anonymous 

structs

unions

 are a Microsoft extension

-Wmicrosoft-cast

This diagnostic is enabled by default.

Diagnostic text:

warning: static_cast between pointer-to-function and pointer-to-object is a Microsoft extension

warning: implicit conversion between pointer-to-function and pointer-to-object is a Microsoft extension

-Wmicrosoft-charize

Diagnostic text:

warning: charizing operator #@ is a Microsoft extension

-Wmicrosoft-comment-paste

Diagnostic text:

warning: pasting two ‘/’ tokens into a ‘//’ comment is a Microsoft extension

-Wmicrosoft-const-init

This diagnostic is enabled by default.

Diagnostic text:

warning: default initialization of an object of const type A

 without a user-provided default constructor

 is a Microsoft extension

-Wmicrosoft-cpp-macro

Diagnostic text:

warning: C++ operator A (aka B) used as a macro name

-Wmicrosoft-default-arg-redefinition

This diagnostic is enabled by default.

Diagnostic text:

warning: redefinition of default argument

-Wmicrosoft-drectve-section

This diagnostic is enabled by default.

Diagnostic text:

warning: #pragma A(“.drectve”) has undefined behavior, use #pragma comment(linker, …) instead

-Wmicrosoft-end-of-file

Diagnostic text:

warning: treating Ctrl-Z as end-of-file is a Microsoft extension

-Wmicrosoft-enum-forward-reference

This diagnostic is enabled by default.

Diagnostic text:

warning: forward references to ‘enum’ types are a Microsoft extension

-Wmicrosoft-enum-value

Diagnostic text:

warning: enumerator value is not representable in the underlying type A

-Wmicrosoft-exception-spec

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: exception specification of ‘…’ is a Microsoft extension

warning: 

pointer to 

reference to 

incomplete type B is not allowed in exception specification

warning: exception specification in declaration does not match previous declaration

warning: exception specification in explicit instantiation does not match instantiated one

warning: A is missing exception specification ‘B

warning: exception specification of overriding function is more lax than base version

-Wmicrosoft-exists

This diagnostic is enabled by default.

Diagnostic text:

warning: dependent 

__if_not_exists

__if_exists

 declarations are ignored

-Wmicrosoft-explicit-constructor-call

This diagnostic is enabled by default.

Diagnostic text:

warning: explicit constructor calls are a Microsoft extension

-Wmicrosoft-extra-qualification

This diagnostic is enabled by default.

Diagnostic text:

warning: extra qualification on member A

-Wmicrosoft-fixed-enum

Diagnostic text:

warning: enumeration types with a fixed underlying type are a Microsoft extension

-Wmicrosoft-flexible-array

Diagnostic text:

warning: flexible array member A in otherwise empty 

struct

interface

union

class

enum

 is a Microsoft extension

warning: flexible array member A in a union is a Microsoft extension

-Wmicrosoft-goto

This diagnostic is enabled by default.

Diagnostic text:

warning: jump from this goto statement to its label is a Microsoft extension

-Wmicrosoft-inaccessible-base

This diagnostic is enabled by default.

Diagnostic text:

warning: accessing inaccessible direct base A of B is a Microsoft extension

-Wmicrosoft-include

This diagnostic is enabled by default.

Diagnostic text:

warning: #include resolved using non-portable Microsoft search rules as: A

-Wmicrosoft-mutable-reference

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘mutable’ on a reference type is a Microsoft extension

-Wmicrosoft-pure-definition

This diagnostic is enabled by default.

Diagnostic text:

warning: function definition with pure-specifier is a Microsoft extension

-Wmicrosoft-redeclare-static

Diagnostic text:

warning: redeclaring non-static A as static is a Microsoft extension

-Wmicrosoft-sealed

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘sealed’ keyword is a Microsoft extension

-Wmicrosoft-template

This diagnostic is enabled by default.

Also controls -Wmicrosoft-template-shadow.

Diagnostic text:

warning: duplicate explicit instantiation of A ignored as a Microsoft extension

warning: use of identifier A found via unqualified lookup into dependent bases of class templates is a Microsoft extension

warning: using the undeclared type A as a default template argument is a Microsoft extension

warning: non-type template argument containing a dereference operation is a Microsoft extension

warning: 

class template

class template partial

variable template

variable template partial

function template

member function

static data member

member class

member enumeration

 specialization of B not in 

a namespace enclosing C

class C or an enclosing namespace

 is a Microsoft extension

warning: template argument for template type parameter must be a type; omitted ‘typename’ is a Microsoft extension

warning: ‘static’ can only be specified inside the class definition

warning: use of undeclared identifier A; unqualified lookup into dependent bases of class template B is a Microsoft extension

-Wmicrosoft-template-shadow

This diagnostic is enabled by default.

Diagnostic text:

warning: declaration of A shadows template parameter

-Wmicrosoft-union-member-reference

This diagnostic is enabled by default.

Diagnostic text:

warning: union member A has reference type B, which is a Microsoft extension

-Wmicrosoft-unqualified-friend

This diagnostic is enabled by default.

Diagnostic text:

warning: unqualified friend declaration referring to type outside of the nearest enclosing namespace is a Microsoft extension; add a nested name specifier

-Wmicrosoft-using-decl

This diagnostic is enabled by default.

Diagnostic text:

warning: using declaration referring to inaccessible member ‘A’ (which refers to accessible member ‘B’) is a Microsoft compatibility extension

-Wmicrosoft-void-pseudo-dtor

This diagnostic is enabled by default.

Diagnostic text:

warning: pseudo-destructors on type void are a Microsoft extension

-Wmisexpect

Diagnostic text:

warning: Potential performance regression from use of __builtin_expect(): Annotation was correct on A of profiled executions.

-Wmisleading-indentation

Diagnostic text:

warning: misleading indentation; statement is not part of the previous ‘

if

else

for

while

-Wmismatched-new-delete

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘delete

[]

‘ applied to a pointer that was allocated with ‘new

[]

‘; did you mean ‘delete

[]

‘?

-Wmismatched-parameter-types

This diagnostic is enabled by default.

Diagnostic text:

warning: conflicting parameter types in implementation of A

-Wmismatched-return-types

This diagnostic is enabled by default.

Diagnostic text:

warning: conflicting return type in implementation of A

-Wmismatched-tags

Diagnostic text:

warning: C defined as 

a struct

an interface

a class

 template

 here but previously declared as 

a struct

an interface

a class

 template

; this is valid, but may result in linker errors under the Microsoft C++ ABI

warning: 

struct

interface

class

 template

 C was previously declared as a 

struct

interface

class

 template

; this is valid, but may result in linker errors under the Microsoft C++ ABI

-Wmissing-braces

Diagnostic text:

warning: suggest braces around initialization of subobject

-Wmissing-constinit

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘constinit’ specifier missing on initializing declaration of A

-Wmissing-declarations

This diagnostic is enabled by default.

Diagnostic text:

warning: declaration does not declare anything

warning: A’ is not permitted on a declaration of a type

warning: typedef requires a name

warning: A’ ignored on this declaration

-Wmissing-exception-spec

This diagnostic is enabled by default.

Diagnostic text:

warning: A is missing exception specification ‘B

-Wmissing-field-initializers

Diagnostic text:

warning: missing field A initializer

-Wmissing-format-attribute

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wmissing-include-dirs

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wmissing-method-return-type

Diagnostic text:

warning: method has no return type specified; defaults to ‘id’

-Wmissing-noescape

This diagnostic is enabled by default.

Diagnostic text:

warning: parameter of overriding method should be annotated with __attribute__((noescape))

-Wmissing-noreturn

Diagnostic text:

warning: block could be declared with attribute ‘noreturn’

warning: 

function

method

 B could be declared with attribute ‘noreturn’

-Wmissing-prototype-for-cc

This diagnostic is enabled by default.

Diagnostic text:

warning: function with no prototype cannot use the A calling convention

-Wmissing-prototypes

Diagnostic text:

warning: no previous prototype for function A

-Wmissing-selector-name

This diagnostic is enabled by default.

Diagnostic text:

warning: A used as the name of the previous parameter rather than as part of the selector

-Wmissing-sysroot

This diagnostic is enabled by default.

Diagnostic text:

warning: no such sysroot directory: ‘A

-Wmissing-variable-declarations

Diagnostic text:

warning: no previous extern declaration for non-static variable A

-Rmodule-build

Diagnostic text:

remark: building module ‘A’ as ‘B

remark: finished building module ‘A

remark: could not acquire lock file for module ‘A’: B

remark: timed out waiting to acquire lock file for module ‘A

-Wmodule-conflict

This diagnostic is enabled by default.

Diagnostic text:

warning: module ‘A’ conflicts with already-imported module ‘B’: C

warning: module file ‘A’ was validated as a system module and is now being imported as a non-system module; any difference in diagnostic options will be ignored

-Wmodule-file-config-mismatch

This diagnostic is an error by default, but the flag -Wno-module-file-config-mismatch can be used to disable the error.

Diagnostic text:

error: module file A cannot be loaded due to a configuration mismatch with the current compilation

-Wmodule-file-extension

This diagnostic is enabled by default.

Diagnostic text:

warning: duplicate module file extension block name ‘A

-Rmodule-import

Diagnostic text:

remark: importing module ‘A

 into ‘D

 from ‘B

-Wmodule-import-in-extern-c

This diagnostic is an error by default, but the flag -Wno-module-import-in-extern-c can be used to disable the error.

Diagnostic text:

error: import of C++ module ‘A’ appears within extern “C” language linkage specification

-Wmodules-ambiguous-internal-linkage

This diagnostic is enabled by default.

Diagnostic text:

warning: ambiguous use of internal linkage declaration A defined in multiple modules

-Wmodules-import-nested-redundant

This diagnostic is an error by default, but the flag -Wno-modules-import-nested-redundant can be used to disable the error.

Diagnostic text:

error: redundant #include of module ‘A’ appears within B

-Wmsvc-not-found

This diagnostic is enabled by default.

Diagnostic text:

warning: unable to find a Visual Studio installation; try running Clang from a developer command prompt

-Wmultichar

This diagnostic is enabled by default.

Diagnostic text:

warning: multi-character character constant

-Wmultiple-move-vbase

This diagnostic is enabled by default.

Diagnostic text:

warning: defaulted move assignment operator of A will move assign virtual base class B multiple times

-Wnested-anon-types

Diagnostic text:

warning: anonymous types declared in an anonymous 

struct

union

 are an extension

-Wnested-externs

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wnew-returns-null

This diagnostic is enabled by default.

Diagnostic text:

warning: A should not return a null pointer unless it is declared ‘throw()’

 or ‘noexcept’

-Wnewline-eof

Diagnostic text:

warning: no newline at end of file

warning: no newline at end of file

-Wnoderef

This diagnostic is enabled by default.

Diagnostic text:

warning: dereferencing A; was declared with a ‘noderef’ type

warning: dereferencing expression marked as ‘noderef’

warning: casting to dereferenceable pointer removes ‘noderef’ attribute

-Wnon-gcc

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wconversion, -Wliteral-range, -Wsign-compare.

-Wnon-literal-null-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: expression which evaluates to zero treated as a null pointer constant of type A

-Wnon-modular-include-in-framework-module

Diagnostic text:

warning: include of non-modular header inside framework module ‘A’: ‘B

-Wnon-modular-include-in-module

Also controls -Wnon-modular-include-in-framework-module.

Diagnostic text:

warning: include of non-modular header inside module ‘A’: ‘B

-Wnon-pod-varargs

This diagnostic is an error by default, but the flag -Wno-non-pod-varargs can be used to disable the error.

Diagnostic text:

error: cannot pass object of 

non-POD

non-trivial

 type B through variadic 

function

block

method

constructor

; call will abort at runtime

error: cannot pass 

non-POD

non-trivial

 object of type B to variadic 

function

block

method

constructor

; expected type from format string was D

error: second argument to ‘va_arg’ is of non-POD type A

error: second argument to ‘va_arg’ is of ARC ownership-qualified type A

-Wnon-virtual-dtor

Diagnostic text:

warning: A has virtual functions but non-virtual destructor

-Wnonnull

This diagnostic is enabled by default.

Diagnostic text:

warning: null passed to a callee that requires a non-null argument

warning: null returned from 

function

method

 that requires a non-null return value

-Wnonportable-cfstrings

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wnonportable-include-path

This diagnostic is enabled by default.

Diagnostic text:

warning: non-portable path to file ‘A’; specified path differs in case from file name on disk

-Wnonportable-system-include-path

Diagnostic text:

warning: non-portable path to file ‘A’; specified path differs in case from file name on disk

-Wnonportable-vector-initialization

This diagnostic is enabled by default.

Diagnostic text:

warning: vector initializers are not compatible with NEON intrinsics in big endian mode

-Wnontrivial-memaccess

This diagnostic is enabled by default.

Diagnostic text:

warning: 

destination for

source of

first operand of

second operand of

 this B call is a pointer to record C that is not trivial to 

primitive-default-initialize

primitive-copy

-Wnsconsumed-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: overriding method has mismatched ns_consumed attribute on its parameter

-Wnsreturns-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: overriding method has mismatched ns_returns_

not_retained

retained

 attributes

-Wnull-arithmetic

This diagnostic is enabled by default.

Diagnostic text:

warning: use of NULL in arithmetic operation

warning: comparison between NULL and non-pointer 

(B and NULL)

(NULL and B)

-Wnull-character

This diagnostic is enabled by default.

Diagnostic text:

warning: null character(s) preserved in 

char

string

 literal

warning: null character ignored

-Wnull-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit conversion of 

NULL

nullptr

 constant to B

-Wnull-dereference

This diagnostic is enabled by default.

Diagnostic text:

warning: binding dereferenced null pointer to reference has undefined behavior

warning: indirection of non-volatile null pointer will be deleted, not trap

-Wnull-pointer-arithmetic

Diagnostic text:

warning: arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension

warning: performing pointer arithmetic on a null pointer has undefined behavior

 if the offset is nonzero

-Wnullability

This diagnostic is enabled by default.

Diagnostic text:

warning: conflicting nullability specifier on parameter types, A conflicts with existing specifier B

warning: conflicting nullability specifier on return types, A conflicts with existing specifier B

warning: nullability specifier A conflicts with existing specifier B

warning: synthesized setter A for null_resettable property B does not handle nil

warning: duplicate nullability specifier A

-Wnullability-completeness

This diagnostic is enabled by default.

Also controls -Wnullability-completeness-on-arrays.

Diagnostic text:

warning: 

pointer

block pointer

member pointer

 is missing a nullability type specifier (_Nonnull, _Nullable, or _Null_unspecified)

-Wnullability-completeness-on-arrays

This diagnostic is enabled by default.

Diagnostic text:

warning: array parameter is missing a nullability type specifier (_Nonnull, _Nullable, or _Null_unspecified)

-Wnullability-declspec

This diagnostic is an error by default, but the flag -Wno-nullability-declspec can be used to disable the error.

Diagnostic text:

error: nullability specifier A cannot be applied to non-pointer type B; did you mean to apply the specifier to the 

pointer

block pointer

member pointer

function pointer

member function pointer

?

-Wnullability-extension

Diagnostic text:

warning: type nullability specifier A is a Clang extension

-Wnullability-inferred-on-nested-type

This diagnostic is enabled by default.

Diagnostic text:

warning: inferring ‘_Nonnull’ for pointer type within 

array

reference

 is deprecated

-Wnullable-to-nonnull-conversion

Diagnostic text:

warning: implicit conversion from nullable pointer A to non-nullable pointer type B

-Wobjc-autosynthesis-property-ivar-name-match

This diagnostic is enabled by default.

Diagnostic text:

warning: autosynthesized property A will use 

synthesized

 instance variable C, not existing instance variable D

-Wobjc-bool-constant-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit conversion from constant value A to ‘BOOL’; the only well defined values for ‘BOOL’ are YES and NO

-Wobjc-boxing

This diagnostic is enabled by default.

Diagnostic text:

warning: string is ill-formed as UTF-8 and will become a null A when boxed

-Wobjc-circular-container

This diagnostic is enabled by default.

Diagnostic text:

warning: adding A to B might cause circular dependency in container

-Wobjc-designated-initializers

This diagnostic is enabled by default.

Diagnostic text:

warning: designated initializer missing a ‘super’ call to a designated initializer of the super class

warning: designated initializer invoked a non-designated initializer

warning: designated initializer should only invoke a designated initializer on ‘super’

warning: method override for the designated initializer of the superclass A not found

warning: convenience initializer missing a ‘self’ call to another initializer

warning: convenience initializer should not invoke an initializer on ‘super’

-Wobjc-flexible-array

This diagnostic is enabled by default.

Diagnostic text:

warning: field A can overwrite instance variable B with variable sized type C in superclass D

warning: field A with variable sized type B is not visible to subclasses and can conflict with their instance variables

-Wobjc-forward-class-redefinition

This diagnostic is enabled by default.

Diagnostic text:

warning: redefinition of forward class A of a typedef name of an object type is ignored

-Wobjc-interface-ivars

Diagnostic text:

warning: declaration of instance variables in the interface is deprecated

-Wobjc-literal-compare

This diagnostic is enabled by default.

Also controls -Wobjc-string-compare.

Diagnostic text:

warning: direct comparison of 

an array literal

a dictionary literal

a numeric literal

a boxed expression

 has undefined behavior

-Wobjc-literal-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit boolean conversion of Objective-C object literal always evaluates to true

warning: object of type A is not compatible with 

array element type

dictionary key type

dictionary value type

 C

-Wobjc-macro-redefinition

This diagnostic is enabled by default.

Diagnostic text:

warning: ignoring redefinition of Objective-C qualifier macro

-Wobjc-messaging-id

Diagnostic text:

warning: messaging unqualified id

-Wobjc-method-access

This diagnostic is enabled by default.

Diagnostic text:

warning: class method A not found (return type defaults to ‘id’)

warning: class method A not found (return type defaults to ‘id’); did you mean C?

warning: instance method A not found (return type defaults to ‘id’)

warning: instance method A not found (return type defaults to ‘id’); did you mean C?

warning: instance method A found instead of class method B

warning: instance method A is being used on ‘Class’ which is not in the root class

-Wobjc-missing-property-synthesis

Diagnostic text:

warning: auto property synthesis is synthesizing property not explicitly synthesized

-Wobjc-missing-super-calls

This diagnostic is enabled by default.

Diagnostic text:

warning: method possibly missing a [super A] call

-Wobjc-multiple-method-names

This diagnostic is enabled by default.

Diagnostic text:

warning: multiple methods named A found

-Wobjc-noncopy-retain-block-property

This diagnostic is enabled by default.

Diagnostic text:

warning: retain’ed block property does not copy the block - use copy attribute instead

-Wobjc-nonunified-exceptions

This diagnostic is enabled by default.

Diagnostic text:

warning: cannot catch an exception thrown with @throw in C++ in the non-unified exception model

-Wobjc-property-assign-on-object-type

Diagnostic text:

warning: ‘assign’ property of object type may become a dangling reference; consider using ‘unsafe_unretained’

-Wobjc-property-implementation

This diagnostic is enabled by default.

Diagnostic text:

warning: class property A requires method B to be defined - use @dynamic or provide a method implementation in this class implementation

warning: class property A requires method B to be defined - use @dynamic or provide a method implementation in this category

warning: property A requires method B to be defined - use @synthesize, @dynamic or provide a method implementation in this class implementation

warning: property A requires method B to be defined - use @dynamic or provide a method implementation in this category

-Wobjc-property-implicit-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: primary property declaration is implicitly strong while redeclaration in class extension is weak

-Wobjc-property-matches-cocoa-ownership-rule

This diagnostic is enabled by default.

Diagnostic text:

warning: property follows Cocoa naming convention for returning ‘owned’ objects

-Wobjc-property-no-attribute

This diagnostic is enabled by default.

Diagnostic text:

warning: default property attribute ‘assign’ not appropriate for object

warning: no ‘assign’, ‘retain’, or ‘copy’ attribute is specified - ‘assign’ is assumed

-Wobjc-property-synthesis

This diagnostic is enabled by default.

Diagnostic text:

warning: auto property synthesis will not synthesize property A; it will be implemented by its superclass, use @dynamic to acknowledge intention

warning: auto property synthesis will not synthesize property A because it is ‘readwrite’ but it will be synthesized ‘readonly’ via another property

warning: auto property synthesis will not synthesize property A because it cannot share an ivar with another synthesized property

-Wobjc-protocol-method-implementation

This diagnostic is enabled by default.

Diagnostic text:

warning: category is implementing a method which will also be implemented by its primary class

-Wobjc-protocol-property-synthesis

This diagnostic is enabled by default.

Diagnostic text:

warning: auto property synthesis will not synthesize property A declared in protocol B

-Wobjc-protocol-qualifiers

This diagnostic is enabled by default.

Diagnostic text:

warning: parameterized class A already conforms to the protocols listed; did you forget a ‘*’?

-Wobjc-readonly-with-setter-property

This diagnostic is enabled by default.

Diagnostic text:

warning: setter cannot be specified for a readonly property

-Wobjc-redundant-literal-use

This diagnostic is enabled by default.

Diagnostic text:

warning: using A with a literal is redundant

-Wobjc-root-class

This diagnostic is enabled by default.

Diagnostic text:

warning: class A defined without specifying a base class

-Wobjc-signed-char-bool-implicit-float-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: implicit conversion from floating-point type A to ‘BOOL’

-Wobjc-signed-char-bool-implicit-int-conversion

Diagnostic text:

warning: implicit conversion from integral type A to ‘BOOL’

-Wobjc-string-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: direct comparison of a string literal has undefined behavior

-Wobjc-string-concatenation

This diagnostic is enabled by default.

Diagnostic text:

warning: concatenated NSString literal for an NSArray expression - possibly missing a comma

-Wobjc-unsafe-perform-selector

This diagnostic is enabled by default.

Diagnostic text:

warning: A is incompatible with selectors that return a 

struct

union

vector

 type

-Wodr

This diagnostic is enabled by default.

Diagnostic text:

warning: template parameter lists have a different number of parameters (A vs B)

warning: template parameter has different kinds in different translation units

warning: field A declared with incompatible types in different translation units (B vs. C)

warning: external function A declared with incompatible types in different translation units (B vs. C)

warning: instance variable A declared with incompatible types in different translation units (B vs. C)

warning: non-type template parameter declared with incompatible types in different translation units (A vs. B)

warning: 

class

instance

 method B has a different number of parameters in different translation units (C vs. D)

warning: 

class

instance

 method B has a parameter with a different types in different translation units (C vs. D)

warning: 

class

instance

 method B has incompatible result types in different translation units (C vs. D)

warning: 

class

instance

 method B is variadic in one translation unit and not variadic in another

warning: property A is implemented with 

@synthesize

@dynamic

 in one translation but 

@dynamic

@synthesize

 in another translation unit

warning: property A declared with incompatible types in different translation units (B vs. C)

warning: class A has incompatible superclasses

warning: property A is synthesized to different ivars in different translation units (B vs. C)

warning: parameter kind mismatch; parameter is 

not a

a

 parameter pack

warning: type A has incompatible definitions in different translation units

warning: external variable A defined in multiple translation units

warning: external variable A declared with incompatible types in different translation units (B vs. C)

-Wold-style-cast

Diagnostic text:

warning: use of old-style cast

-Wold-style-definition

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wopencl-unsupported-rgba

This diagnostic is enabled by default.

Diagnostic text:

warning: vector component name ‘A’ is an OpenCL version 2.2 feature

-Wopenmp

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wopenmp-clauses, -Wopenmp-loop-form, -Wopenmp-mapping, -Wopenmp-target, -Wsource-uses-openmp.

-Wopenmp-clauses

This diagnostic is enabled by default.

Diagnostic text:

warning: aligned clause will be ignored because the requested alignment is not a power of 2

warning: allocator with the ‘thread’ trait access has unspecified behavior on ‘A’ directive

warning: unknown context selector in ‘A’ context selector set of ‘omp declare variant’ directive, ignored

warning: zero linear step (A 

and other variables in clause 

should probably be const)

warning: more than one ‘device_type’ clause is specified

warning: allocate directive specifies 

default

B

 allocator while previously used 

default

D

-Wopenmp-loop-form

This diagnostic is enabled by default.

Diagnostic text:

warning: initialization clause of OpenMP for loop is not in canonical form (‘var = init’ or ‘T var = init’)

warning: OpenMP loop iteration variable cannot have more than 64 bits size and will be narrowed

-Wopenmp-mapping

This diagnostic is enabled by default.

Diagnostic text:

warning: Type A is not trivially copyable and not guaranteed to be mapped correctly

-Wopenmp-target

This diagnostic is enabled by default.

Also controls -Wopenmp-mapping.

Diagnostic text:

warning: The OpenMP offloading target ‘A’ is similar to target ‘B’ already specified - will be ignored.

warning: No library ‘A’ found in the default clang lib directory or in LIBRARY_PATH. Expect degraded performance due to no inlining of runtime functions on target devices.

warning: declaration marked as declare target after first use, it may lead to incorrect results

warning: declaration is not declared in any declare target region

-Woption-ignored

This diagnostic is enabled by default.

Diagnostic text:

warning: option ‘-ffine-grained-bitfield-accesses’ cannot be enabled together with a sanitizer; flag ignored

warning: The ‘A’ architecture does not support -moutline; flag ignored

warning: option ‘A’ was ignored by the PS4 toolchain, using ‘-fPIC’

warning: ignoring ‘-mlong-calls’ option as it is not currently supported with 

the implicit usage of 

-mabicalls

warning: ignoring ‘A’ option as it cannot be used with 

implicit usage of

 -mabicalls and the N64 ABI

warning: auto-vectorization requires HVX, use -mhvx to enable it

-Wordered-compare-function-pointers

This diagnostic is enabled by default.

Diagnostic text:

warning: ordered comparison of function pointers (A and B)

-Wout-of-line-declaration

This diagnostic is an error by default, but the flag -Wno-out-of-line-declaration can be used to disable the error.

Diagnostic text:

error: out-of-line declaration of a member must be a definition

-Wout-of-scope-function

This diagnostic is enabled by default.

Diagnostic text:

warning: use of out-of-scope declaration of A

 whose type is not compatible with that of an implicit declaration

-Wover-aligned

Diagnostic text:

warning: type A requires B bytes of alignment and the default allocator only guarantees C bytes

-Woverflow

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Woverlength-strings

Diagnostic text:

warning: string literal of length A exceeds maximum length B that 

C90

ISO C99

C++

 compilers are required to support

-Woverloaded-shift-op-parentheses

This diagnostic is enabled by default.

Diagnostic text:

warning: overloaded operator 

>>

<<

 has higher precedence than comparison operator

-Woverloaded-virtual

Diagnostic text:

warning: A hides overloaded virtual 

function

functions

-Woverride-module

This diagnostic is enabled by default.

Diagnostic text:

warning: overriding the module target triple with A

-Woverriding-method-mismatch

Diagnostic text:

warning: conflicting distributed object modifiers on parameter type in declaration of A

warning: conflicting parameter types in declaration of A

warning: conflicting distributed object modifiers on return type in declaration of A

warning: conflicting return type in declaration of A

warning: conflicting variadic declaration of method and its implementation

warning: conflicting parameter types in declaration of A: B vs C

warning: conflicting return type in declaration of A: B vs C

-Woverriding-t-option

This diagnostic is enabled by default.

Diagnostic text:

warning: overriding ‘A’ option with ‘B

-Wpacked

Diagnostic text:

warning: packed attribute is unnecessary for A

-Wpadded

Diagnostic text:

warning: padding 

struct

interface

class

 B with C 

byte

bit

s

 to align anonymous bit-field

warning: padding 

struct

interface

class

 B with C 

byte

bit

s

 to align E

warning: padding size of A with B 

byte

bit

s

 to alignment boundary

-Wparentheses

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wbitwise-conditional-parentheses, -Wbitwise-op-parentheses, -Wdangling-else, -Wlogical-not-parentheses, -Wlogical-op-parentheses, -Woverloaded-shift-op-parentheses, -Wparentheses-equality, -Wshift-op-parentheses.

Diagnostic text:

warning: using the result of an assignment as a condition without parentheses

warning: A has lower precedence than B; B will be evaluated first

warning: operator ‘?:’ has lower precedence than ‘A’; ‘A’ will be evaluated first

-Wparentheses-equality

This diagnostic is enabled by default.

Diagnostic text:

warning: equality comparison with extraneous parentheses

-Rpass

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-Rpass-analysis

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

remark: A; allow reordering by specifying ‘#pragma clang loop vectorize(enable)’ before the loop. If the arrays will always be independent specify ‘#pragma clang loop vectorize(assume_safety)’ before the loop or provide the ‘__restrict__’ qualifier with the independent array arguments. Erroneous results will occur if these options are incorrectly applied!

remark: A; allow reordering by specifying ‘#pragma clang loop vectorize(enable)’ before the loop or by providing the compiler option ‘-ffast-math’.

-Wpass-failed

This diagnostic is enabled by default.

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-Rpass-missed

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-Wpch-date-time

This diagnostic is enabled by default.

Diagnostic text:

warning: 

precompiled header

module

 uses __DATE__ or __TIME__

-Wpedantic

Also controls -Wc++11-extra-semi, -Wc++11-long-long, -Wc++14-binary-literal, -Wc++20-designator, -Wc11-extensions, -Wcomplex-component-init, -Wdeclaration-after-statement, -Wdollar-in-identifier-extension, -Wembedded-directive, -Wempty-translation-unit, -Wfixed-enum-extension, -Wflexible-array-extensions, -Wfour-char-constants, -Wgnu-anonymous-struct, -Wgnu-auto-type, -Wgnu-binary-literal, -Wgnu-case-range, -Wgnu-complex-integer, -Wgnu-compound-literal-initializer, -Wgnu-conditional-omitted-operand, -Wgnu-empty-initializer, -Wgnu-empty-struct, -Wgnu-flexible-array-initializer, -Wgnu-flexible-array-union-member, -Wgnu-folding-constant, -Wgnu-imaginary-constant, -Wgnu-include-next, -Wgnu-label-as-value, -Wgnu-redeclared-enum, -Wgnu-statement-expression, -Wgnu-union-cast, -Wgnu-zero-line-directive, -Wgnu-zero-variadic-macro-arguments, -Wimport-preprocessor-directive-pedantic, -Wkeyword-macro, -Wlanguage-extension-token, -Wlong-long, -Wmicrosoft-charize, -Wmicrosoft-comment-paste, -Wmicrosoft-cpp-macro, -Wmicrosoft-end-of-file, -Wmicrosoft-enum-value, -Wmicrosoft-fixed-enum, -Wmicrosoft-flexible-array, -Wmicrosoft-redeclare-static, -Wnested-anon-types, -Wnullability-extension, -Woverlength-strings, -Wretained-language-linkage, -Wundefined-internal-type, -Wvla-extension, -Wzero-length-array.

Diagnostic text:

warning: duplicate ‘A’ declaration specifier

warning: ‘enable_if’ is a clang extension

warning: ‘diagnose_if’ is a clang extension

warning: designated initializers are a C99 feature

warning: ISO C++ does not allow ‘main’ to be used by a program

warning: C++98 requires an accessible copy constructor for class C when binding a reference to a temporary; was 

private

protected

warning: anonymous 

struct

union

 cannot be ‘B

warning: no viable constructor 

copying variable

copying parameter

returning object

initializing statement expression result

throwing object

copying member subobject

copying array element

allocating object

copying temporary

initializing base subobject

initializing vector element

capturing value

 of type B; C++98 requires a copy constructor when binding a reference to a temporary

warning: ISO C++ standards before C++17 do not allow new expression for type A to use list-initialization

warning: parameter A was not declared, defaulting to type ‘int’

warning: invoking a pointer to a ‘const &’ member function on an rvalue is a C++20 extension

warning: qualifier in explicit instantiation of A requires a template-id (a typedef is not permitted)

warning: static 

function

variable

 B is used in an inline function with external linkage

warning: ISO C forbids forward references to ‘enum’ types

warning: ISO C restricts enumerator values to range of ‘int’ (A is too 

small

large

)

warning: size of static array must be an integer constant expression

warning: initializer for aggregate is not a compile-time constant

warning: flexible array members are a C99 feature

warning: invalid application of ‘

sizeof

alignof

vec_step

__builtin_omp_required_simd_align

__alignof

‘ to a function type

warning: invalid application of ‘

sizeof

alignof

vec_step

__builtin_omp_required_simd_align

__alignof

‘ to a void type

warning: ISO C90 does not allow subscripting non-lvalue array

warning: subscript of a pointer to void is a GNU extension

warning: ISO C forbids taking the address of an expression of type ‘void’

warning: ordered comparison between pointer and zero (A and B) is an extension

warning: equality comparison between function pointer and void pointer (A and B)

warning: arithmetic on

 a

 pointer

s

 to void is a GNU extension

warning: arithmetic on

 a

 pointer

s

 to

 the

 function type

s

 B

 and D

 is a GNU extension

warning: ISO C does not support ‘++’/’–’ on complex integer type A

warning: ISO C does not support ‘~’ for complex conjugation of A

warning: complex numbers are an extension in a freestanding C99 implementation

warning: cast between pointer-to-function and pointer-to-object is an extension

warning: implicit conversion from array size expression of type A to 

integral

enumeration

 type C is a C++11 extension

warning: 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

 converts between void pointer and function pointer

warning: kernel function A is a member function; this may not be accepted by nvcc

warning: C99 forbids conditional expressions with only one void side

warning: C99 forbids casting nonscalar type A to the same type

warning: use of the A attribute is a C++14 extension

warning: use of the A attribute is a C++17 extension

warning: use of the A attribute is a C++20 extension

warning: types declared in an anonymous 

struct

union

 are a Microsoft extension

warning: format specifies type A but the argument has 

type

underlying type

 B

warning: void 

function

method

block

 A should not return void expression

warning: 

qualifier in 

static 

array size 

‘[*] ‘

is a C99 feature

warning: extra ‘;’ 

outside of a function

inside a B

inside instance variable list

after member function definition

warning: ’__thread’ before ‘A

warning: type-less parameter names in function declaration

warning: variable declaration in for loop is a C99-specific feature

warning: compound literals are a C99-specific feature

warning: commas at the end of enumerator lists are a C99-specific feature

warning: commas at the end of enumerator lists are a C++11 extension

warning: enumeration types with a fixed underlying type are a C++11 extension

warning: A’ is a C99 extension

warning: use of GNU array range extension

warning: exception specification of ‘…’ is a Microsoft extension

warning: attributes on 

a namespace

an enumerator

 declaration are a C++17 extension

warning: extern templates are a C++11 extension

warning: multi-line // comment

warning: // comments are not allowed in this language

warning: no newline at end of file

warning: use of non-standard escape character ‘\A

warning: hexadecimal floating constants are a C99 feature

warning: hexadecimal floating literals are a C++17 feature

warning: #ident is a language extension

warning: #warning is a language extension

warning: comma operator in operand of #if

warning: __VA_ARGS__ can only appear in the expansion of a C99 variadic macro

warning: variadic macros are a C99 feature

warning: named variadic macros are a GNU extension

warning: empty macro arguments are a C99 feature

warning: variadic macros are a Clang extension in OpenCL

warning: C requires #line number to be less than A, allowed as extension

warning: macro expansion producing ‘defined’ has undefined behavior

-Wpedantic-core-features

Diagnostic text:

warning: OpenCL extension A is core feature or supported optional core feature - ignoring

-Wpessimizing-move

Diagnostic text:

warning: moving a temporary object prevents copy elision

warning: moving a local object in a return statement prevents copy elision

-Wpointer-arith

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: arithmetic on

 a

 pointer

s

 to

 the

 function type

s

 B

 and D

 is a GNU extension

warning: subscript of a pointer to void is a GNU extension

warning: arithmetic on

 a

 pointer

s

 to void is a GNU extension

warning: invalid application of ‘

sizeof

alignof

vec_step

__builtin_omp_required_simd_align

__alignof

‘ to a function type

warning: invalid application of ‘

sizeof

alignof

vec_step

__builtin_omp_required_simd_align

__alignof

‘ to a void type

warning: subtraction of pointers to type A of zero size has undefined behavior

-Wpointer-bool-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: nonnull 

function call

parameter

 B’ will evaluate to ‘true’ on first encounter

warning: address of

 function

 array

 B’ will always evaluate to ‘true’

-Wpointer-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: comparing a pointer to a null character constant; did you mean to compare to 

NULL

(void *)0

?

-Wpointer-integer-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: comparison between pointer and integer (A and B)

-Wpointer-sign

This diagnostic is enabled by default.

Diagnostic text:

warning: 

assigning to different types

passing to parameter of different type

returning from function with different return type

converting between types

initializing with expression of different type

sending to parameter of different type

casting between types

 converts between pointers to integer types with different sign

-Wpointer-to-int-cast

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wpointer-type-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: pointer type mismatch

-Wpoison-system-directories

Diagnostic text:

warning: include location ‘A’ is unsafe for cross-compilation

-Wpotentially-evaluated-expression

This diagnostic is enabled by default.

Diagnostic text:

warning: expression with side effects will be evaluated despite being used as an operand to ‘typeid’

-Wpragma-clang-attribute

This diagnostic is enabled by default.

Diagnostic text:

warning: unused attribute A in ‘#pragma clang attribute push’ region

-Wpragma-once-outside-header

This diagnostic is enabled by default.

Diagnostic text:

warning: #pragma once in main file

-Wpragma-pack

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wpragma-pack-suspicious-include.

Diagnostic text:

warning: the current #pragma pack alignment value is modified in the included file

warning: unterminated ‘#pragma pack (push, …)’ at end of file

-Wpragma-pack-suspicious-include

Diagnostic text:

warning: non-default #pragma pack value changes the alignment of struct or union members in the included file

-Wpragma-system-header-outside-header

This diagnostic is enabled by default.

Diagnostic text:

warning: #pragma system_header ignored in main file

-Wpragmas

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wignored-pragmas, -Wpragma-clang-attribute, -Wpragma-pack, -Wunknown-pragmas.

Diagnostic text:

warning: #pragma redefine_extname is applicable to external C declarations only; not applied to 

function

variable

 B

-Wpredefined-identifier-outside-function

This diagnostic is enabled by default.

Diagnostic text:

warning: predefined identifier is only valid inside function

-Wprivate-extern

This diagnostic is enabled by default.

Diagnostic text:

warning: use of __private_extern__ on a declaration may not produce external symbol private to the linkage unit and is deprecated

-Wprivate-header

This diagnostic is an error by default, but the flag -Wno-private-header can be used to disable the error.

Diagnostic text:

error: use of private header from outside its module: ‘A

-Wprivate-module

This diagnostic is enabled by default.

Diagnostic text:

warning: expected canonical name for private module ‘A

warning: private submodule ‘A’ in private module map, expected top-level module

warning: module ‘A’ already re-exported as ‘B

warning: no submodule named A in module ‘B’; using top level ‘C

-Wprofile-instr-missing

Diagnostic text:

warning: profile data may be incomplete: of A function

s

, B 

has

have

 no data

-Wprofile-instr-out-of-date

This diagnostic is enabled by default.

Diagnostic text:

warning: profile data may be out of date: of A function

s

, B 

has

have

 mismatched data that will be ignored

-Wprofile-instr-unprofiled

This diagnostic is enabled by default.

Diagnostic text:

warning: no profile data available for file “A

-Wproperty-access-dot-syntax

This diagnostic is enabled by default.

Diagnostic text:

warning: property A not found on object of type B; did you mean to access property C?

-Wproperty-attribute-mismatch

This diagnostic is enabled by default.

Diagnostic text:

warning: property attribute in class extension does not match the primary class

warning: B’ attribute on property A does not match the property inherited from C

warning: getter name mismatch between property redeclaration (B) and its original declaration (A)

warning: attribute ‘readonly’ of property A restricts attribute ‘readwrite’ of property inherited from B

-Wprotocol

This diagnostic is enabled by default.

Diagnostic text:

warning: method A in protocol B not implemented

-Wprotocol-property-synthesis-ambiguity

This diagnostic is enabled by default.

Diagnostic text:

warning: property 

of type B

with attribute ‘B

without attribute ‘B

with getter B

with setter B

 was selected for synthesis

-Wqualified-void-return-type

This diagnostic is enabled by default.

Diagnostic text:

warning: function cannot return qualified void type A

-Wquoted-include-in-framework-header

Diagnostic text:

warning: double-quoted include “A” in framework header, expected angle-bracketed instead

-Wrange-loop-bind-reference

Diagnostic text:

warning: loop variable A is always a copy because the range of type B does not return a reference

-Wrange-loop-construct

Diagnostic text:

warning: loop variable A  is initialized with a value of a different type resulting in a copy

warning: loop variable A of type B creates a copy from type C

-Wreadonly-iboutlet-property

This diagnostic is enabled by default.

Diagnostic text:

warning: readonly IBOutlet property A when auto-synthesized may not work correctly with ‘nib’ loader

-Wreceiver-expr

This diagnostic is enabled by default.

Diagnostic text:

warning: receiver type A is not ‘id’ or interface pointer, consider casting it to ‘id’

-Wreceiver-forward-class

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: receiver A is a forward class and corresponding @interface may not exist

warning: receiver type A for instance message is a forward declaration

-Wredeclared-class-member

This diagnostic is enabled by default.

Diagnostic text:

warning: class member cannot be redeclared

-Wredundant-decls

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wredundant-move

Diagnostic text:

warning: redundant move in return statement

-Wredundant-parens

Diagnostic text:

warning: redundant parentheses surrounding declarator

-Wregister

This diagnostic is enabled by default.

Also controls -Wdeprecated-register.

Diagnostic text:

error: ISO C++17 does not allow ‘register’ storage class specifier

-Wreinterpret-base-class

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘reinterpret_cast’ 

from

to

 class A 

to

from

 its 

virtual base

base at non-zero offset

 B behaves differently from ‘static_cast’

-Rremark-backend-plugin

Diagnostic text:

The text of this diagnostic is not controlled by Clang.

-Wreorder

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wreorder-ctor, -Wreorder-init-list.

-Wreorder-ctor

Diagnostic text:

warning: 

field

base class

 B will be initialized after 

field

base

 D

-Wreorder-init-list

This diagnostic is enabled by default.

Diagnostic text:

warning: ISO C++ requires field designators to be specified in declaration order; field B will be initialized after field A

-Wrequires-expression

This diagnostic is enabled by default.

Diagnostic text:

warning: this requires expression will only be checked for syntactic validity; did you intend to place it in a nested requirement? (add another ‘requires’ before the expression)

-Wrequires-super-attribute

This diagnostic is enabled by default.

Diagnostic text:

warning: A attribute cannot be applied to 

methods in protocols

dealloc

-Wreserved-id-macro

Diagnostic text:

warning: macro name is a reserved identifier

-Wreserved-user-defined-literal

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wc++11-compat-reserved-user-defined-literal.

Diagnostic text:

warning: invalid suffix on literal; C++11 requires a space between literal and identifier

error: invalid suffix on literal; C++11 requires a space between literal and identifier

-Wretained-language-linkage

Diagnostic text:

warning: friend function A retaining previous language linkage is an extension

-Wreturn-stack-address

This diagnostic is enabled by default.

Diagnostic text:

warning: returning address of label, which is local

warning: returning 

address of

reference to

 local temporary object

warning: 

address of

reference to

 stack memory associated with 

local variable

parameter

 B returned

-Wreturn-std-move

Diagnostic text:

warning: local variable A will be copied despite being 

returned

thrown

 by name

-Wreturn-std-move-in-c++11

Diagnostic text:

warning: prior to the resolution of a defect report against ISO C++11, local variable A would have been copied despite being returned by name, due to its not matching the function return type

-Wreturn-type

This diagnostic is enabled by default.

Also controls -Wreturn-type-c-linkage.

Diagnostic text:

error: 

void function

void method

constructor

destructor

 A should not return a value

error: non-void 

function

method

 A should return a value

warning: non-void coroutine does not return a value

warning: non-void function does not return a value

warning: non-void lambda does not return a value

warning: non-void coroutine does not return a value in all control paths

warning: non-void function does not return a value in all control paths

warning: non-void lambda does not return a value in all control paths

error: non-void 

function

method

 A should return a value

-Wreturn-type-c-linkage

This diagnostic is enabled by default.

Diagnostic text:

warning: A has C-linkage specified, but returns user-defined type B which is incompatible with C

warning: A has C-linkage specified, but returns incomplete type B which could be incompatible with C

-Rsanitize-address

Diagnostic text:

remark: -fsanitize-address-field-padding applied to A

remark: -fsanitize-address-field-padding ignored for A because it 

is not C++

is packed

is a union

is trivially copyable

has trivial destructor

is standard layout

is in a blacklisted file

is blacklisted

-Wsection

This diagnostic is enabled by default.

Diagnostic text:

warning: section attribute is specified on redeclared variable

warning: duplicate code segment specifiers

warning: 

codeseg

section

 does not match previous declaration

-Wselector

Also controls -Wselector-type-mismatch.

Diagnostic text:

warning: no method with selector A is implemented in this translation unit

-Wselector-type-mismatch

Diagnostic text:

warning: several methods with selector A of mismatched types are found for the @selector expression

-Wself-assign

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wself-assign-field, -Wself-assign-overloaded.

Diagnostic text:

warning: explicitly assigning value of variable of type A to itself

-Wself-assign-field

This diagnostic is enabled by default.

Diagnostic text:

warning: assigning 

field

instance variable

 to itself

-Wself-assign-overloaded

Diagnostic text:

warning: explicitly assigning value of variable of type A to itself

-Wself-move

Diagnostic text:

warning: explicitly moving variable of type A to itself

-Wsemicolon-before-method-body

Diagnostic text:

warning: semicolon before method body is ignored

-Wsentinel

This diagnostic is enabled by default.

Diagnostic text:

warning: missing sentinel in 

function call

method dispatch

block call

warning: not enough variable arguments in A declaration to fit a sentinel

-Wserialized-diagnostics

This diagnostic is enabled by default.

Diagnostic text:

warning: unable to open file A for serializing diagnostics (B)

warning: unable to merge a subprocess’s serialized diagnostics

-Wshadow

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wshadow-field-in-constructor-modified, -Wshadow-ivar.

Diagnostic text:

warning: declaration shadows a 

local variable

variable in C

static data member of C

field of C

typedef in C

type alias in C

-Wshadow-all

Some of the diagnostics controlled by this flag are enabled by default.

Controls -Wshadow, -Wshadow-field, -Wshadow-field-in-constructor, -Wshadow-uncaptured-local.

-Wshadow-field

Diagnostic text:

warning: 

parameter

non-static data member

 A 

of B 

shadows member inherited from type C

-Wshadow-field-in-constructor

Also controls -Wshadow-field-in-constructor-modified.

Diagnostic text:

warning: constructor parameter A shadows the field B of C

-Wshadow-field-in-constructor-modified

Diagnostic text:

warning: modifying constructor parameter A that shadows a field of B

-Wshadow-ivar

This diagnostic is enabled by default.

Diagnostic text:

warning: local declaration of A hides instance variable

-Wshadow-uncaptured-local

Diagnostic text:

warning: declaration shadows a 

local variable

variable in C

static data member of C

field of C

typedef in C

type alias in C

-Wshift-count-negative

This diagnostic is enabled by default.

Diagnostic text:

warning: shift count is negative

-Wshift-count-overflow

This diagnostic is enabled by default.

Diagnostic text:

warning: shift count >= width of type

-Wshift-negative-value

This diagnostic is enabled by default.

Diagnostic text:

warning: shifting a negative signed value is undefined

-Wshift-op-parentheses

This diagnostic is enabled by default.

Diagnostic text:

warning: operator ‘A’ has lower precedence than ‘B’; ‘B’ will be evaluated first

-Wshift-overflow

This diagnostic is enabled by default.

Diagnostic text:

warning: signed shift result (A) requires B bits to represent, but C only has D bits

-Wshift-sign-overflow

Diagnostic text:

warning: signed shift result (A) sets the sign bit of the shift expression’s type (B) and becomes negative

-Wshorten-64-to-32

Diagnostic text:

warning: implicit conversion loses integer precision: A to B

-Wsign-compare

Diagnostic text:

warning: comparison of integers of different signs: A and B

-Wsign-conversion

Diagnostic text:

warning: implicit conversion changes signedness: A to B

warning: operand of ? changes signedness: A to B

warning: the resulting value is always non-negative after implicit conversion

-Wsign-promo

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wsigned-enum-bitfield

Diagnostic text:

warning: enums in the Microsoft ABI are signed integers by default; consider giving the enum A an unsigned underlying type to make this code portable

-Wsigned-unsigned-wchar

This diagnostic is an error by default, but the flag -Wno-signed-unsigned-wchar can be used to disable the error.

Diagnostic text:

error: A’ cannot be signed or unsigned

-Wsizeof-array-argument

This diagnostic is enabled by default.

Diagnostic text:

warning: sizeof on array function parameter will return size of A instead of B

-Wsizeof-array-decay

This diagnostic is enabled by default.

Diagnostic text:

warning: sizeof on pointer operation will return size of A instead of B

-Wsizeof-array-div

This diagnostic is enabled by default.

Diagnostic text:

warning: expression does not compute the number of elements in this array; element type is A, not B

-Wsizeof-pointer-div

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ will return the size of the pointer, not the array itself

-Wsizeof-pointer-memaccess

This diagnostic is enabled by default.

Diagnostic text:

warning: A’ call operates on objects of type B while the size is based on a different type C

warning: argument to ‘sizeof’ in A call is the same pointer type B as the 

destination

source

; expected D or an explicit length

-Wslash-u-filename

This diagnostic is enabled by default.

Diagnostic text:

warning: ’/UA’ treated as the ‘/U’ option

-Wsometimes-uninitialized

Diagnostic text:

warning: variable A is 

used

captured

 uninitialized whenever 

D’ condition is 

true

false

D’ loop 

is entered

exits because its condition is false

D’ loop 

condition is true

exits because its condition is false

switch D is taken

its declaration is reached

D is called

-Wsource-uses-openmp

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: ’#pragma omp declare variant’ cannot be applied to the function that was defined already; the original function might be used

warning: ’#pragma omp declare variant’ cannot be applied for function after first usage; the original function might be used

warning: variant function in ‘#pragma omp declare variant’ is itself marked as ‘#pragma omp declare variant’

warning: OpenMP only allows an ordered construct with the simd clause nested in a simd construct

warning: unexpected ‘#pragma omp …’ in program

-Wspir-compat

Diagnostic text:

warning: sampler initializer has invalid A bits

-Wstack-exhausted

This diagnostic is enabled by default.

Diagnostic text:

warning: stack nearly exhausted; compilation time may suffer, and crashes due to stack overflow are likely

-Wstack-protector

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstatic-float-init

This diagnostic is enabled by default.

Also controls -Wgnu-static-float-init.

Diagnostic text:

error: in-class initializer for static data member of type A requires ‘constexpr’ specifier

-Wstatic-in-inline

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: static 

function

variable

 B is used in an inline function with external linkage

warning: static 

function

variable

 B is used in an inline function with external linkage

-Wstatic-inline-explicit-instantiation

This diagnostic is enabled by default.

Diagnostic text:

warning: ignoring ‘

static

inline

‘ keyword on explicit template instantiation

-Wstatic-local-in-inline

This diagnostic is enabled by default.

Diagnostic text:

warning: non-constant static local variable in inline function may be different in different files

-Wstatic-self-init

This diagnostic is enabled by default.

Diagnostic text:

warning: static variable A is suspiciously used within its own initialization

-Wstdlibcxx-not-found

This diagnostic is enabled by default.

Diagnostic text:

warning: include path for libstdc++ headers not found; pass ‘-stdlib=libc++’ on the command line to use the libc++ standard library instead

-Wstrict-aliasing

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-aliasing=0

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-aliasing=1

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-aliasing=2

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow=0

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow=1

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow=2

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow=3

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow=4

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-overflow=5

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wstrict-prototypes

Diagnostic text:

warning: this 

function declaration is not

block declaration is not

old-style function definition is not preceded by

 a prototype

-Wstrict-prototypes

Diagnostic text:

warning: this 

function declaration is not

block declaration is not

old-style function definition is not preceded by

 a prototype

-Wstrict-selector-match

Diagnostic text:

warning: multiple methods named A found

-Wstring-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: result of comparison against 

a string literal

@encode

 is unspecified (use an explicit string comparison function instead)

-Wstring-conversion

Diagnostic text:

warning: implicit conversion turns string literal into bool: A to B

-Wstring-plus-char

This diagnostic is enabled by default.

Diagnostic text:

warning: adding A to a string pointer does not append to the string

-Wstring-plus-int

This diagnostic is enabled by default.

Diagnostic text:

warning: adding A to a string does not append to the string

-Wstrlcpy-strlcat-size

This diagnostic is enabled by default.

Diagnostic text:

warning: size argument in A call appears to be size of the source; expected the size of the destination

-Wstrncat-size

This diagnostic is enabled by default.

Diagnostic text:

warning: the value of the size argument in ‘strncat’ is too large, might lead to a buffer overflow

warning: size argument in ‘strncat’ call appears to be size of the source

warning: the value of the size argument to ‘strncat’ is wrong

-Wsuper-class-method-mismatch

Diagnostic text:

warning: method parameter type does not match super class method parameter type

-Wsuspicious-bzero

This diagnostic is enabled by default.

Diagnostic text:

warning: ‘size’ argument to bzero is ‘0’

-Wswitch

This diagnostic is enabled by default.

Diagnostic text:

warning: overflow converting case value to switch condition type (A to B)

warning: 

enumeration value B not handled in switch

enumeration values B and C not handled in switch

enumeration values B, C, and D not handled in switch

A enumeration values not handled in switch: B, C, D

warning: case value not in enumerated type A

-Wswitch-bool

This diagnostic is enabled by default.

Diagnostic text:

warning: switch condition has boolean value

-Wswitch-default

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wswitch-enum

Diagnostic text:

warning: 

enumeration value B not explicitly handled in switch

enumeration values B and C not explicitly handled in switch

enumeration values B, C, and D not explicitly handled in switch

A enumeration values not explicitly handled in switch: B, C, D

-Wsync-fetch-and-nand-semantics-changed

This diagnostic is enabled by default.

Diagnostic text:

warning: the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here

-Wsynth

This diagnostic flag exists for GCC compatibility, and has no effect in Clang.

-Wtautological-bitwise-compare

Diagnostic text:

warning: bitwise comparison always evaluates to 

false

true

warning: bitwise or with non-zero value always evaluates to true

-Wtautological-compare

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wtautological-bitwise-compare, -Wtautological-constant-compare, -Wtautological-objc-bool-compare, -Wtautological-overlap-compare, -Wtautological-pointer-compare, -Wtautological-undefined-compare.

Diagnostic text:

warning: 

aligning a value

the result of checking whether a value is aligned

 to 1 byte is 

a no-op

always true

warning: 

self-

array 

comparison always evaluates to 

a constant

true

false

‘std::strong_ordering::equal’

-Wtautological-constant-compare

This diagnostic is enabled by default.

Also controls -Wtautological-constant-out-of-range-compare.

Diagnostic text:

warning: converting the result of ‘?:’ with integer constants to a boolean always evaluates to ‘true’

warning: converting the result of ‘<<’ to a boolean always evaluates to 

false

true

warning: result of comparison of 

constant A

true

false

 with 

expression of type C

boolean expression

 is always E

-Wtautological-constant-out-of-range-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: result of comparison of 

constant A

true

false

 with 

expression of type C

boolean expression

 is always E

-Wtautological-objc-bool-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: result of comparison of constant A with expression of type ‘BOOL’ is always B, as the only well defined values for ‘BOOL’ are YES and NO

-Wtautological-overlap-compare

Diagnostic text:

warning: overlapping comparisons always evaluate to 

false

true

-Wtautological-pointer-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: comparison of nonnull 

function call

parameter

 B 

not 

equal to a null pointer is ‘

true

false

‘ on first encounter

warning: comparison of 

address of

function

array

 B 

not 

equal to a null pointer is always 

true

false

-Wtautological-type-limit-compare

Diagnostic text:

warning: result of comparison 

D

B

 C 

B

D

 is always E

-Wtautological-undefined-compare

This diagnostic is enabled by default.

Diagnostic text:

warning: reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to 

true

false

warning: ‘this’ pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to 

true

false

-Wtautological-unsigned-enum-zero-compare

Diagnostic text:

warning: result of comparison of 

D

unsigned enum expression

 C 

unsigned enum expression

D

 is always E

-Wtautological-unsigned-zero-compare

Diagnostic text:

warning: result of comparison of 

D

unsigned expression

 C 

unsigned expression

D

 is always E

-Wtentative-definition-incomplete-type

This diagnostic is enabled by default.

Diagnostic text:

warning: tentative definition of variable with internal linkage has incomplete non-array type A

-Wthread-safety-analysis

Diagnostic text:

warning: A B’ must be acquired before ‘C

warning: Cycle in acquired_before/after dependencies, starting with ‘A

warning: cannot resolve lock expression

warning: acquiring A B’ that is already held

warning: expecting A B’ to be held at start of each loop

warning: expecting A B’ to be held at the end of function

warning: cannot call function ‘B’ while A C’ is held

warning: calling function B requires holding A 

C

C’ exclusively

warning: A B’ is acquired exclusively and shared in the same scope

warning: A B’ is not held on every path through here

warning: A B’ is still held at the end of function

warning: releasing A B’ that was not held

warning: releasing A B’ using 

shared

exclusive

 access, expected 

shared

exclusive

 access

warning: 

reading

writing

 the value pointed to by A requires holding 

any mutex

any mutex exclusively

warning: 

reading

writing

 the value pointed to by B requires holding A 

C

C’ exclusively

warning: 

reading

writing

 variable A requires holding 

any mutex

any mutex exclusively

warning: 

reading

writing

 variable B requires holding A 

C

C’ exclusively

-Wthread-safety-attributes

Diagnostic text:

warning: invalid capability name ‘A’; capability name must be ‘mutex’ or ‘role’

warning: A attribute requires arguments whose type is annotated with ‘capability’ attribute; type here is B

warning: A attribute can only be applied in a context annotated with ‘capability(“mutex”)’ attribute

warning: A only applies to pointer types; type here is B

warning: ignoring A attribute because its argument is invalid

warning: A attribute without capability arguments refers to ‘this’, but B isn’t annotated with ‘capability’ or ‘scoped_lockable’ attribute

warning: A attribute without capability arguments can only be applied to non-static methods of a class

-Wthread-safety-beta

Diagnostic text:

warning: Thread safety beta warning.

-Wthread-safety-negative

Diagnostic text:

warning: acquiring A B’ requires negative capability ‘C

-Wthread-safety-precise

Diagnostic text:

warning: calling function B requires holding A 

C

C’ exclusively

warning: 

reading

writing

 the value pointed to by B requires holding A 

C

C’ exclusively

warning: 

reading

writing

 variable B requires holding A 

C

C’ exclusively

-Wthread-safety-reference

Diagnostic text:

warning: passing variable B by reference requires holding A 

C

C’ exclusively

warning: passing the value that B points to by reference requires holding A 

C

C’ exclusively

-Wthread-safety-verbose

Diagnostic text:

warning: Thread safety verbose warning.

-Wtrigraphs

This diagnostic is enabled by default.

Diagnostic text:

warning: trigraph converted to ‘A’ character

warning: trigraph ends block comment

warning: trigraph ignored

warning: ignored trigraph would end block comment

-Wtype-safety

This diagnostic is enabled by default.

Diagnostic text:

warning: specified A type tag requires a null pointer

warning: argument type A doesn’t match specified B type tag 

that requires D

warning: this type tag was not designed to be used with this function

-Wtypedef-redefinition

This diagnostic is enabled by default.

Diagnostic text:

warning: redefinition of typedef A is a C11 feature

-Wtypename-missing

This diagnostic is enabled by default.

Diagnostic text:

warning: missing ‘typename’ prior to dependent type name ‘AB

-Wunable-to-open-stats-file

This diagnostic is enabled by default.

Diagnostic text:

warning: unable to open statistics output file ‘A’: ‘B

-Wunavailable-declarations

This diagnostic is enabled by default.

Diagnostic text:

warning: A may be unavailable because the receiver type is unknown

-Wundeclared-selector

Diagnostic text:

warning: undeclared selector A

warning: undeclared selector A; did you mean B?

-Wundef

Diagnostic text:

warning: A is not defined, evaluates to 0

-Wundefined-bool-conversion

This diagnostic is enabled by default.

Diagnostic text:

warning: reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed to always convert to true

warning: ‘this’ pointer cannot be null in well-defined C++ code; pointer may be assumed to always convert to true

-Wundefined-func-template

Diagnostic text:

warning: instantiation of function A required here, but no definition is available

-Wundefined-inline

This diagnostic is enabled by default.

Diagnostic text:

warning: inline function A is not defined

-Wundefined-internal

This diagnostic is enabled by default.

Diagnostic text:

warning: 

function

variable

 B has internal linkage but is not defined

-Wundefined-internal-type

Diagnostic text:

warning: ISO C++ requires a definition in this translation unit for 

function

variable

 B because its type does not have linkage

-Wundefined-reinterpret-cast

Diagnostic text:

warning: dereference of type B that was reinterpret_cast from type A has undefined behavior

warning: reinterpret_cast from A to B has undefined behavior

-Wundefined-var-template

This diagnostic is enabled by default.

Diagnostic text:

warning: instantiation of variable A required here, but no definition is available

-Wunderaligned-exception-object

This diagnostic is enabled by default.

Diagnostic text:

warning: underaligned exception object thrown

-Wunevaluated-expression

This diagnostic is enabled by default.

Also controls -Wpotentially-evaluated-expression.

Diagnostic text:

warning: expression with side effects has no effect in an unevaluated context

-Wunguarded-availability

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wunguarded-availability-new.

Diagnostic text:

warning: A is only available on B C or newer

-Wunguarded-availability-new

This diagnostic is enabled by default.

Diagnostic text:

warning: A is only available on B C or newer

-Wunicode

This diagnostic is enabled by default.

Diagnostic text:

warning: incomplete universal character name; treating as ‘\’ followed by identifier

warning: \A used with no following hex digits; treating as ‘\’ followed by identifier

warning: universal character name refers to a surrogate character

warning: universal character names are only valid in C99 or C++; treating as ‘\’ followed by identifier

warning: universal character names are only valid in C99 or C++

-Wunicode-homoglyph

This diagnostic is enabled by default.

Diagnostic text:

warning: treating Unicode character <U+A> as identifier character rather than as ‘B’ symbol

-Wunicode-whitespace

This diagnostic is enabled by default.

Diagnostic text:

warning: treating Unicode character as whitespace

-Wunicode-zero-width

This diagnostic is enabled by default.

Diagnostic text:

warning: identifier contains Unicode character <U+A> that is invisible in some environments

-Wuninitialized

Some of the diagnostics controlled by this flag are enabled by default.

Also controls -Wsometimes-uninitialized, -Wstatic-self-init.

Diagnostic text:

warning: base class A is uninitialized when used here to access B

warning: field A is uninitialized when used here

warning: reference A is not yet bound to a value when used here

warning: block pointer variable A is 

uninitialized

null

 when captured by block

warning: variable A is uninitialized when used within its own initialization

warning: reference A is not yet bound to a value when used within its own initialization

warning: variable A is uninitialized when 

used here

captured by block

-Wunknown-argument

This diagnostic is enabled by default.

Diagnostic text:

warning: unknown argument ignored in clang-cl: ‘A

warning: unknown argument ignored in clang-cl ‘A’; did you mean ‘B’?

-Wunknown-attributes

This diagnostic is enabled by default.

Diagnostic text:

warning: unknown attribute A ignored

-Wunknown-cuda-version

This diagnostic is enabled by default.

Diagnostic text:

warning: Unknown CUDA version A. Assuming the latest supported version B

-Wunknown-escape-sequence

This diagnostic is enabled by default.

Diagnostic text:

warning: unknown escape sequence ‘\A

-Wunknown-pragmas

Some of the diagnostics controlled by this flag are enabled by default.

Diagnostic text:

warning: expected ‘ON’ or ‘OFF’ or ‘DEFAULT’ in pragma

warning: expected end of directive in pragma

<