blob: baab5d97bc2a1e195572f1279036a5bdfb3e794c [file] [log] [blame]
dnl as-compiler-flag.m4 0.1.0
dnl autostars m4 macro for detection of compiler flags
dnl David Schleef <ds@schleef.org>
dnl $Id: as-compiler-flag.m4,v 1.1 2005/12/15 23:35:19 ds Exp $
dnl AS_COMPILER_FLAG(CFLAGS, ACTION-IF-ACCEPTED, [ACTION-IF-NOT-ACCEPTED])
dnl Tries to compile with the given CFLAGS.
dnl Runs ACTION-IF-ACCEPTED if the compiler can compile with the flags,
dnl and ACTION-IF-NOT-ACCEPTED otherwise.
AC_DEFUN([AS_COMPILER_FLAG],
[
AC_MSG_CHECKING([to see if compiler understands $1])
save_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS $1"
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],[])], [flag_ok=yes], [flag_ok=no])
CFLAGS="$save_CFLAGS"
if test "X$flag_ok" = Xyes ; then
m4_ifvaln([$2],[$2])
true
else
m4_ifvaln([$3],[$3])
true
fi
AC_MSG_RESULT([$flag_ok])
])
dnl AS_COMPILER_FLAGS(VAR, FLAGS)
dnl Tries to compile with the given CFLAGS.
AC_DEFUN([AS_COMPILER_FLAGS],
[
list=$2
flags_supported=""
flags_unsupported=""
AC_MSG_CHECKING([for supported compiler flags])
for each in $list
do
save_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS $each"
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],[])], [flag_ok=yes], [flag_ok=no])
CFLAGS="$save_CFLAGS"
if test "X$flag_ok" = Xyes ; then
flags_supported="$flags_supported $each"
else
flags_unsupported="$flags_unsupported $each"
fi
done
AC_MSG_RESULT([$flags_supported])
if test "X$flags_unsupported" != X ; then
AC_MSG_WARN([unsupported compiler flags: $flags_unsupported])
fi
$1="$$1 $flags_supported"
])