diff --git a/Makefile b/Makefile
index 14ced32..8859946 100644
--- a/Makefile
+++ b/Makefile
@@ -78,7 +78,7 @@ $(1)/%: $(2)%.in $(LIBUTILS)
 	@$(RM) "$$@"
 	@{ echo -n 'm4_changequote([[[,]]])'; cat $$<; } | m4 -P --define=m4_devtools_version=$$(BUILDTOOLVER) | $(edit) >$$@
 	@chmod $(3) "$$@"
-	@bash -n "$$@"
+	@bash -O extglob -n "$$@"
 endef
 
 $(eval $(call buildInScript,build/bin,src/,555))
diff --git a/lib/common.sh b/lib/common.sh
index a5e4616..d345307 100644
--- a/lib/common.sh
+++ b/lib/common.sh
@@ -137,6 +137,7 @@ pkgver_equal() {
 #    $pkgver can be supplied with or without a pkgrel appended.
 #    If not supplied, any pkgrel will be matched.
 ##
+shopt -s extglob
 find_cached_package() {
 	local searchdirs=("$PWD" "$PKGDEST") results=()
 	local targetname=$1 targetver=$2 targetarch=$3
@@ -191,7 +192,7 @@ find_cached_package() {
 			return 1
 	esac
 }
-
+shopt -u extglob
 
 check_package_validity(){
 	local pkgfile=$1
diff --git a/src/diffpkg.in b/src/diffpkg.in
index 10b0904..6d07419 100644
--- a/src/diffpkg.in
+++ b/src/diffpkg.in
@@ -248,6 +248,7 @@ diff_pkgs() {
 	fi
 }
 
+shopt -s extglob
 fetch_pkg() {
 	local pkg pkgdest pkgurl
 	case $1 in
@@ -295,6 +296,7 @@ fetch_pkg() {
 
 	echo "$pkgdest"
 }
+shopt -u extglob
 
 if (( $# < 2 )); then
 	if [[ ! -f PKGBUILD ]]; then
diff --git a/src/find-libdeps.in b/src/find-libdeps.in
index 5a11580..2517879 100644
--- a/src/find-libdeps.in
+++ b/src/find-libdeps.in
@@ -40,6 +40,7 @@ else
 	pushd "$WORKDIR" >/dev/null
 fi
 
+shopt -s extglob
 process_sofile() {
 	# extract the library name: libfoo.so
 	shopt -s extglob nullglob
@@ -56,6 +57,7 @@ process_sofile() {
 		soobjects+=("${soname}=${soversion}-${soarch}")
 	fi
 }
+shopt -u extglob
 
 case $script_mode in
 	deps) find_args=(-perm -u+x);;