sys-devel/gcc-10.2.0-r5: add patch for Xcode 12.5

Closes: https://bugs.gentoo.org/799170
Package-Manager: Portage-3.0.21-prefix, Repoman-3.0.3
Signed-off-by: Fabian Groffen <grobian@gentoo.org>

2 files changed, 150 insertions, 0 deletions

diff --git a/sys-devel/gcc/files/gcc-10.2.0-xcode-12.5.patch b/sys-devel/gcc/files/gcc-10.2.0-xcode-12.5.patch
new file mode 100644
index 0000000000..f8b6b04232
--- /dev/null
+++ b/sys-devel/gcc/files/gcc-10.2.0-xcode-12.5.patch
@@ -0,0 +1,147 @@
+From 743b8dd6fd757e997eb060d70fd4ae8e04fb56cd Mon Sep 17 00:00:00 2001
+From: Iain Sandoe <iain@sandoe.co.uk>
+Date: Sat, 31 Jul 2021 16:29:03 +0100
+Subject: [PATCH 1/1] Darwin, X86, config: Adjust 'as' command lines
+ [PR100340].
+
+Versions of the assembler using clang from XCode 12.5/12.5.1
+have a bug which produces different code layout between debug and
+non-debug input, leading to a compare fail for default configure
+parameters.
+
+This is a workaround fix to disable the optimisation that is
+responsible for the bug.
+
+Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
+
+PR target/100340 - Bootstrap fails with Clang 12.0.5 (XCode 12.5)
+
+	PR target/100340
+
+gcc/ChangeLog:
+
+	* config.in: Regenerate.
+	* config/i386/darwin.h (EXTRA_ASM_OPTS): New
+	(ASM_SPEC): Pass options to disable branch shortening where
+	needed.
+	* configure: Regenerate.
+	* configure.ac: Detect versions of 'as' that support the
+	optimisation which has the bug.
+---
+ gcc/config.in            |  7 +++++++
+ gcc/config/i386/darwin.h | 10 +++++++++-
+ gcc/configure            | 35 +++++++++++++++++++++++++++++++++++
+ gcc/configure.ac         |  9 +++++++++
+ 4 files changed, 60 insertions(+), 1 deletion(-)
+
+diff --git a/gcc/config.in b/gcc/config.in
+index 7f5b01fad76..d8a810bbc91 100644
+--- a/gcc/config.in
++++ b/gcc/config.in
+@@ -616,6 +616,13 @@
+ #endif
+ 
+ 
++/* Define if your Mac OS X assembler supports -mllvm -x86-pad-for-align=false.
++   */
++#ifndef USED_FOR_TARGET
++#undef HAVE_AS_MLLVM_X86_PAD_FOR_ALIGN
++#endif
++
++
+ /* Define if your Mac OS X assembler supports the -mmacos-version-min option.
+    */
+ #ifndef USED_FOR_TARGET
+diff --git a/gcc/config/i386/darwin.h b/gcc/config/i386/darwin.h
+index bac32197e83..73b06e2307d 100644
+--- a/gcc/config/i386/darwin.h
++++ b/gcc/config/i386/darwin.h
+@@ -125,10 +125,18 @@ along with GCC; see the file COPYING3.  If not see
+   %{mfentry*:%eDarwin does not support -mfentry or associated options}" \
+   DARWIN_CC1_SPEC
+ 
++/* This is a workaround for a tool bug: see PR100340.  */
++
++#ifdef HAVE_AS_MLLVM_X86_PAD_FOR_ALIGN
++#define EXTRA_ASM_OPTS " -mllvm -x86-pad-for-align=false"
++#else
++#define EXTRA_ASM_OPTS ""
++#endif
++
+ #undef ASM_SPEC
+ #define ASM_SPEC "-arch %(darwin_arch) \
+   " ASM_OPTIONS " -force_cpusubtype_ALL \
+-  %{static}" ASM_MMACOSX_VERSION_MIN_SPEC
++  %{static}" ASM_MMACOSX_VERSION_MIN_SPEC EXTRA_ASM_OPTS
+ 
+ #undef ENDFILE_SPEC
+ #define ENDFILE_SPEC \
+diff --git a/gcc/configure b/gcc/configure
+index 08c286764e0..a2d1003a0f5 100755
+--- a/gcc/configure
++++ b/gcc/configure
+@@ -27082,6 +27082,41 @@ $as_echo "$as_me: WARNING: LTO for $target requires binutils >= 2.20.1, but vers
+ 	fi
+ 	;;
+     esac
++    case $target_os in
++       darwin2[0-9]* | darwin19*)
++        { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for llvm assembler x86-pad-for-align option" >&5
++$as_echo_n "checking assembler for llvm assembler x86-pad-for-align option... " >&6; }
++if ${gcc_cv_as_mllvm_x86_pad_for_align+:} false; then :
++  $as_echo_n "(cached) " >&6
++else
++  gcc_cv_as_mllvm_x86_pad_for_align=no
++  if test x$gcc_cv_as != x; then
++    $as_echo '.text' > conftest.s
++    if { ac_try='$gcc_cv_as $gcc_cv_as_flags -mllvm -x86-pad-for-align=false -o conftest.o conftest.s >&5'
++  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
++  (eval $ac_try) 2>&5
++  ac_status=$?
++  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
++  test $ac_status = 0; }; }
++    then
++	gcc_cv_as_mllvm_x86_pad_for_align=yes
++    else
++      echo "configure: failed program was" >&5
++      cat conftest.s >&5
++    fi
++    rm -f conftest.o conftest.s
++  fi
++fi
++{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_as_mllvm_x86_pad_for_align" >&5
++$as_echo "$gcc_cv_as_mllvm_x86_pad_for_align" >&6; }
++if test $gcc_cv_as_mllvm_x86_pad_for_align = yes; then
++
++$as_echo "#define HAVE_AS_MLLVM_X86_PAD_FOR_ALIGN 1" >>confdefs.h
++
++fi
++
++       ;;
++    esac
+ 
+     { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for -xbrace_comment" >&5
+ $as_echo_n "checking assembler for -xbrace_comment... " >&6; }
+diff --git a/gcc/configure.ac b/gcc/configure.ac
+index 653a1cc561d..ad8fa5a4604 100644
+--- a/gcc/configure.ac
++++ b/gcc/configure.ac
+@@ -4799,6 +4799,15 @@ foo:	nop
+ 	fi
+ 	;;
+     esac
++    case $target_os in
++       darwin2[[0-9]]* | darwin19*)
++        gcc_GAS_CHECK_FEATURE([llvm assembler x86-pad-for-align option],
++          gcc_cv_as_mllvm_x86_pad_for_align,,
++          [-mllvm -x86-pad-for-align=false], [.text],,
++          [AC_DEFINE(HAVE_AS_MLLVM_X86_PAD_FOR_ALIGN, 1,
++	    [Define if your Mac OS X assembler supports -mllvm -x86-pad-for-align=false.])])
++       ;;
++    esac
+ 
+     gcc_GAS_CHECK_FEATURE([-xbrace_comment], gcc_cv_as_ix86_xbrace_comment,,
+       [-xbrace_comment=no], [.text],,
+-- 
+2.27.0
+
diff --git a/sys-devel/gcc/gcc-10.2.0-r5.ebuild b/sys-devel/gcc/gcc-10.2.0-r5.ebuild
index f146759e09..9baac7c2d6 100644
--- a/sys-devel/gcc/gcc-10.2.0-r5.ebuild
+++ b/sys-devel/gcc/gcc-10.2.0-r5.ebuild
@@ -53,6 +53,9 @@ src_prepare() {
 	find .  -name "configure" | xargs \
 	sed -i -e '/^\s*10\.\*)/N' \
 		-e '/^\s*10\.\*)\s*_lt_dar_allow_undefined/s/10\.\*/10.*|11.*/' || die
+
+	# fix interoperation with Xcode 12.5, bug #799170
+	eapply -p1 "${FILESDIR}"/${PN}-10.2.0-xcode-12.5.patch
 }
 
 src_configure() {