From f6fc178414eb1193629ebd982be83a786edf9d6a Mon Sep 17 00:00:00 2001
From: Flatcar Buildbot <buildbot@flatcar-linux.org>
Date: Mon, 25 Nov 2024 07:07:56 +0000
Subject: [PATCH] eclass/toolchain: Sync with Gentoo

It's from Gentoo commit 729c11d560d55971b8f46295fce77afc4e895265.
---
 .../portage-stable/eclass/toolchain.eclass    | 44 ++++++++++++++-----
 1 file changed, 32 insertions(+), 12 deletions(-)

diff --git a/sdk_container/src/third_party/portage-stable/eclass/toolchain.eclass b/sdk_container/src/third_party/portage-stable/eclass/toolchain.eclass
index 1f043de0b5..13f3298fea 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/toolchain.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/toolchain.eclass
@@ -333,6 +333,7 @@ if [[ ${PN} != kgcc64 && ${PN} != gcc-* ]] ; then
 	# it was disabled in 13.
 	tc_version_is_at_least 14.0.0_pre20230423 ${PV} && IUSE+=" rust" TC_FEATURES+=( rust )
 	tc_version_is_at_least 14.2.1_p20241026 ${PV} && IUSE+=" time64"
+	tc_version_is_at_least 15.0.0_pre20241124 ${PV} && IUSE+=" libdiagnostics"
 fi
 
 if tc_version_is_at_least 10; then
@@ -575,6 +576,19 @@ toolchain_pkg_pretend() {
 		_tc_use_if_iuse objc++ && \
 			ewarn 'Obj-C++ requires a C++ compiler, disabled due to USE="-cxx"'
 	fi
+
+	# Do the check for pure source builds only, since the override
+	# cannot work with binary packages, see https://bugs.gentoo.org/944198
+	if [[ ${BUILD_TYPE} == source ]] && in_iuse time64 && ! use time64 &&
+		has_version -r "${CATEGORY}/${PN}[time64(-)]" &&
+		[[ ! ${TC_FORCE_TIME32} ]]
+	then
+		eerror "Attempting to build USE=-time64 version of gcc when at least"
+		eerror "one USE=time64 version is installed. Did you accidentally"
+		eerror "switch back to a non-time64 profile? If this is really"
+		eerror "desirable, set TC_FORCE_TIME32=1 to force the build."
+		die "Attempting to build USE=-time64 on a USE=time64 system"
+	fi
 }
 
 #---->> pkg_setup <<----
@@ -1065,7 +1079,7 @@ toolchain_src_configure() {
 
 	downgrade_arch_flags
 	gcc_do_filter_flags
-	if tc_version_is_at_least 14.2.1_p20241026 ${PV}; then
+	if [[ ${PN} != kgcc64 && ${PN} != gcc-* ]] && tc_version_is_at_least 14.2.1_p20241026 ${PV}; then
 		append-cppflags "-D_GENTOO_TIME64_FORCE=$(usex time64 1 0)"
 	fi
 
@@ -1185,11 +1199,13 @@ toolchain_src_configure() {
 		if grep -q "experimental" gcc/DEV-PHASE ; then
 			# Tell users about the non-obvious behavior here so they don't think
 			# e.g. the next GCC release is super slow to compile things.
-			ewarn "Unreleased GCCs default to extra runtime checks even with USE=-debug,"
-			ewarn "matching upstream default behavior. We recommend keeping these enabled."
-			ewarn "The checks (sometimes substantially) increase build time but provide important protection"
-			ewarn "from potential miscompilations (wrong code) by turning them into build-time errors."
-			ewarn "To override (not recommended), set: GCC_CHECKS_LIST=\"release\"."
+			if ! use debug ; then
+				ewarn "Unreleased GCCs default to extra runtime checks even with USE=-debug,"
+				ewarn "matching upstream default behavior. We recommend keeping these enabled."
+				ewarn "The checks (sometimes substantially) increase build time but provide important protection"
+				ewarn "from potential miscompilations (wrong code) by turning them into build-time errors."
+				ewarn "To override (not recommended), set: GCC_CHECKS_LIST=\"release\"."
+			fi
 
 			# - USE=debug for pre-releases: yes,extra,rtl (stornger than USE=debug for releases)
 			# - USE=-debug for pre-releases: yes,extra (following upstream default)
@@ -1588,6 +1604,7 @@ toolchain_src_configure() {
 
 		enable_cet_for 'x86_64' 'gnu' 'cet'
 		enable_cet_for 'aarch64' 'gnu' 'standard-branch-protection'
+		[[ ${CTARGET} == i[34567]86-* ]] && confgcc+=( --disable-cet )
 	fi
 
 	if in_iuse systemtap ; then
@@ -1729,8 +1746,8 @@ toolchain_src_configure() {
 		gcc_shell="${BROOT}"/bin/sh
 	fi
 
-	if is_jit ; then
-		einfo "Configuring JIT gcc"
+	if is_jit || _tc_use_if_iuse libdiagnostics ; then
+		einfo "Configuring shared gcc for JIT/libdiagnostics"
 
 		local confgcc_jit=(
 			"${confgcc[@]}"
@@ -1754,8 +1771,10 @@ toolchain_src_configure() {
 			--disable-nls
 			--disable-objc-gc
 			--disable-systemtap
+
 			--enable-host-shared
 			--enable-languages=jit
+
 			# Might be used for the just-built GCC. Easier to just
 			# respect USE=graphite here in case the user passes some
 			# graphite flags rather than try strip them out.
@@ -1764,6 +1783,10 @@ toolchain_src_configure() {
 			--with-system-zlib
 		)
 
+		if tc_version_is_at_least 15.0.0_pre20241124 ${PV} ; then
+			confgcc_jit+=( $(use_enable libdiagnostics) )
+		fi
+
 		if tc_version_is_at_least 13.1 ; then
 			confgcc_jit+=( --disable-fixincludes )
 		fi
@@ -1956,6 +1979,7 @@ gcc_do_filter_flags() {
 
 	if ver_test -lt 15.1 ; then
 		filter-flags -fdiagnostics-explain-harder -fdiagnostics-details
+		filter-flags -fdiagnostics-set-output=text:experimental-nesting=yes
 	fi
 
 	if is_d ; then
@@ -2267,10 +2291,6 @@ toolchain_src_test() {
 		GCC_TESTS_CFLAGS+=" -fno-stack-clash-protection"
 		GCC_TESTS_CXXFLAGS+=" -fno-stack-clash-protection"
 
-		# configure defaults to '-O2 -g' and some tests expect it
-		# accordingly.
-		GCC_TESTS_CFLAGS+=" -g"
-
 		# TODO: Does this handle s390 (-m31) correctly?
 		# TODO: What if there are multiple ABIs like x32 too?
 		# XXX: Disabled until validate_failures.py can handle 'variants'