asterisk/autoconf/ast_gcc_attribute.m4

28 lines
808 B
Plaintext

# Helper function to check for gcc attributes.
# AST_GCC_ATTRIBUTE([attribute name], [attribute syntax], [attribute scope], [makeopts flag])
AC_DEFUN([AST_GCC_ATTRIBUTE],
[
AC_MSG_CHECKING(for compiler 'attribute $1' support)
saved_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
m4_ifval([$4],$4=0)
ax_cv_have_func_attribute_$1=0
AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM(
m4_ifval([$2],
[$3 void __attribute__(($2)) *test(void *muffin, ...) ;],
[$3 void __attribute__(($1)) *test(void *muffin, ...) {return (void *) 0;}]))],
AC_MSG_RESULT(yes)
m4_ifval([$4],$4=1)
ax_cv_have_func_attribute_$1=1
AC_DEFINE_UNQUOTED([HAVE_ATTRIBUTE_$1], 1, [Define to 1 if your GCC C compiler supports the '$1' attribute.]),
AC_MSG_RESULT(no)
)
m4_ifval([$4],[AC_SUBST($4)])
CFLAGS="$saved_CFLAGS"
]
)