Re: HEADS UP: plan to switch many ports over to GCC 12 soon

[Christoph Badura <bad%bsd.de@localhost>]

On Mon, Jun 17, 2024 at 06:58:42AM -0500, Jason Bacon wrote:
> On 6/16/24 16:59, Thomas Klausner wrote:
> >On Sun, Jun 16, 2024 at 06:40:22AM +1000, Matthew Green wrote:
> >>enjoy and send-pr or email tech-toolchain@ for any issues.
> 
> gcc12 still doesn't build on macOS.

For me gcc/usr.bin/host-libcpp failed to build on macOS 12.7.

Stuff like:
src/external/gpl3/gcc/dist/libcpp/include/line-map.h:1677:44: warning: deleted function definitions are a C++11 extension [-Wc++11-extensions]
src/external/gpl3/gcc/dist/libcpp/include/cpplib.h:319:13: warning: commas at the end of enumerator lists are a C++11 extension [-Wc++11-extensions]
src/external/gpl3/gcc/dist/libcpp/include/cpplib.h:1144:6: warning: scoped enumerations are a C++11 extension [-Wc++11-extensions]
etc.

A patch similar what David Gutteridge did on r1.113 of src/tools/gcc/Makefile
fixed that.

diff --git a/external/gpl3/gcc/usr.bin/host-libcpp/Makefile b/external/gpl3/gcc/usr.bin/host-libcpp/Makefile
index 77ea9e0b2ba..e7968c85f55 100644
--- a/external/gpl3/gcc/usr.bin/host-libcpp/Makefile
+++ b/external/gpl3/gcc/usr.bin/host-libcpp/Makefile
@@ -1,5 +1,7 @@
 #	$NetBSD: Makefile,v 1.6 2023/05/19 10:42:34 lukem Exp $
 
+.include <bsd.init.mk>
+
 BUILD_ENV= \
 		AR=${HOST_AR:Q} \
 		AWK=${TOOL_AWK:Q} \
@@ -19,6 +21,12 @@ BUILD_ENV= \
 		RANLIB=${HOST_RANLIB:Q} \
 		YACC=${YACC:Q}
 
+# Force C++11 so builds succeed on hosts where this isn't the compiler
+# default, e.g., NetBSD 8.x with GCC 5.5.
+.if ${HAVE_GCC} > 10
+HOST_CXXFLAGS+=		-std=c++11
+.endif
+
 GMAKE_J_ARGS?=	${MAKEFLAGS:[*]:M*-j*:C/(^|.* )(-j ?[0-9][0-9]*).*/\2/W}
 BUILD_COMMAND=	/usr/bin/env -i ${BUILD_ENV} ${TOOL_GMAKE} ${GMAKE_J_ARGS} -e
 
I'll commit that if there are no objections.
--chris