disable unused result warnings when possible

This commit is contained in:
Benjamin Peterson 2011-09-23 13:23:22 -04:00
parent a1fe1f8dcf
commit 7ddbf10589
2 changed files with 65 additions and 0 deletions

43
configure vendored
View File

@ -5561,6 +5561,49 @@ $as_echo "$ac_cv_no_strict_aliasing" >&6; }
BASECFLAGS="$BASECFLAGS -fno-strict-aliasing"
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if we can turn off $CC unused result warning" >&5
$as_echo_n "checking if we can turn off $CC unused result warning... " >&6; }
ac_save_cc="$CC"
CC="$CC -Wunused-result -Werror"
save_CFLAGS="$CFLAGS"
if ${ac_cv_disable_unused_result_warning+:} false; then :
$as_echo_n "(cached) " >&6
else
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
int
main ()
{
;
return 0;
}
_ACEOF
if ac_fn_c_try_compile "$LINENO"; then :
ac_cv_disable_unused_result_warning=yes
else
ac_cv_disable_unused_result_warning=no
fi
rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
fi
CFLAGS="$save_CFLAGS"
CC="$ac_save_cc"
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_disable_unused_result_warning" >&5
$as_echo "$ac_cv_disable_unused_result_warning" >&6; }
if test $ac_cv_disable_unused_result_warning = yes
then
BASECFLAGS="$BASECFLAGS -Wno-unused-result"
fi
# if using gcc on alpha, use -mieee to get (near) full IEEE 754
# support. Without this, treatment of subnormals doesn't follow
# the standard.

View File

@ -981,6 +981,28 @@ yes)
BASECFLAGS="$BASECFLAGS -fno-strict-aliasing"
fi
AC_MSG_CHECKING(if we can turn off $CC unused result warning)
ac_save_cc="$CC"
CC="$CC -Wunused-result -Werror"
save_CFLAGS="$CFLAGS"
AC_CACHE_VAL(ac_cv_disable_unused_result_warning,
AC_COMPILE_IFELSE(
[
AC_LANG_PROGRAM([[]], [[]])
],[
ac_cv_disable_unused_result_warning=yes
],[
ac_cv_disable_unused_result_warning=no
]))
CFLAGS="$save_CFLAGS"
CC="$ac_save_cc"
AC_MSG_RESULT($ac_cv_disable_unused_result_warning)
if test $ac_cv_disable_unused_result_warning = yes
then
BASECFLAGS="$BASECFLAGS -Wno-unused-result"
fi
# if using gcc on alpha, use -mieee to get (near) full IEEE 754
# support. Without this, treatment of subnormals doesn't follow
# the standard.