--- gettext-tools/gnulib-m4/asm-underscore.m4.orig   2016-08-12 19:58:41.845742375 +0200
+++ gettext-tools/gnulib-m4/asm-underscore.m4      2016-08-12 19:55:53.967056822 +0200
@@ -29,7 +29,7 @@
 EOF
      # Look for the assembly language name in the .s file.
      AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $gl_c_asm_opt conftest.c) >/dev/null 2>&1
-     if LC_ALL=C grep -E '(^|[^a-zA-Z0-9_])_foo([^a-zA-Z0-9_]|$)' conftest.$gl_asmext >/dev/null; then
+     if LC_ALL=C grep -E '(^|[[^a-zA-Z0-9_]])_foo([[^a-zA-Z0-9_]]|$)' conftest.$gl_asmext >/dev/null; then
        gl_cv_prog_as_underscore=yes
      else
        gl_cv_prog_as_underscore=no