Hi Iain,
>> Will comment on the BZ when the bootstrap is done,
>
> Thanks. I'll post a revised patch with the gas_flag handling explained
> before committing.
---------------------------------------------------------------------------
Since
commit 5fc4e333b42d12aca71587f83f2d2c5be9633146
Author: Rainer Orth <[email protected]>
Date: Tue Jan 27 19:15:36 2026 +0100
build: Unify 32 and 64-bit assembler handling
gcc/acinclude.m4 uses gas-only flags --32/--64 on Darwin/x86 with the
native assembler, which breaks many configure tests.
This patch uses the Darwin as options instead, handling the PowerPC
cases at the same time.
Tested on x86_64-apple-darwin21.6.0 and 386-apple-darwin17.7.0.
2026-01-28 Rainer Orth <[email protected]>
gcc:
PR other/123841
* acinclude.m4 (gcc_GAS_FLAGS): Handle Darwin as cases separately.
* configure: Regenerate.
# HG changeset patch
# Parent cd15a6dc87cf118053de20eeb652fb14c0b32fd6
build: Use separate options for Darwin as [PR123841]
diff --git a/gcc/acinclude.m4 b/gcc/acinclude.m4
--- a/gcc/acinclude.m4
+++ b/gcc/acinclude.m4
@@ -465,6 +465,33 @@ dnl #
AC_DEFUN([gcc_GAS_FLAGS],
[AC_CACHE_CHECK([assembler flags], gcc_cv_as_flags,
[ case "$target:$gas_flag" in
+ *-*-darwin*:*)
+ dnl Darwin with the native assembler uses -arch i386/x86_64/ppc/ppc64.
+ dnl
+ dnl Old cctools versions of the Darwin assembler identify as "GNU
+ dnl assembler version 1.38", but still accept the same options as later
+ dnl clang-based ones, so treat them all the same regardless.
+ case "$target" in
+ i?86-*-*)
+ gcc_cv_as_flags="-arch i386"
+ ;;
+ powerpc64*-*-*)
+ gcc_cv_as_flags="-arch ppc64"
+ ;;
+ powerpc*-*-*)
+ gcc_cv_as_flags="-arch ppc"
+ ;;
+ x86_64-*-*)
+ gcc_cv_as_flags="-arch x86_64"
+ ;;
+ esac
+ case "$target" in
+ i?86-*-* | x86_64-*-*)
+ as_32_opt="-arch i386"
+ as_64_opt="-arch x86_64"
+ ;;
+ esac
+ ;;
*-*-solaris2*:no)
dnl Override the default, which may be incompatible.
case "$target" in
@@ -494,10 +521,6 @@ AC_DEFUN([gcc_GAS_FLAGS],
as_32_opt=--32
as_64_opt=--64
;;
- powerpc*-*-darwin*:*)
- dnl Always pass -arch ppc to assembler.
- gcc_cv_as_flags="-arch ppc"
- ;;
amdgcn*:*)
dnl Currently, only the llvm-mc assembler is supported.
dnl Add flags to ensure an amdgcn ELF file is written.
diff --git a/gcc/configure b/gcc/configure
--- a/gcc/configure
+++ b/gcc/configure
@@ -26112,6 +26112,28 @@ if ${gcc_cv_as_flags+:} false; then :
$as_echo_n "(cached) " >&6
else
case "$target:$gas_flag" in
+ *-*-darwin*:*)
+ case "$target" in
+ i?86-*-*)
+ gcc_cv_as_flags="-arch i386"
+ ;;
+ powerpc64*-*-*)
+ gcc_cv_as_flags="-arch ppc64"
+ ;;
+ powerpc*-*-*)
+ gcc_cv_as_flags="-arch ppc"
+ ;;
+ x86_64-*-*)
+ gcc_cv_as_flags="-arch x86_64"
+ ;;
+ esac
+ case "$target" in
+ i?86-*-* | x86_64-*-*)
+ as_32_opt="-arch i386"
+ as_64_opt="-arch x86_64"
+ ;;
+ esac
+ ;;
*-*-solaris2*:no)
case "$target" in
i?86-*-* | sparc-*-*)
@@ -26139,9 +26161,6 @@ else
as_32_opt=--32
as_64_opt=--64
;;
- powerpc*-*-darwin*:*)
- gcc_cv_as_flags="-arch ppc"
- ;;
amdgcn*:*)
gcc_cv_as_flags="--filetype=obj -triple=amdgcn--amdhsa"
;;
