www-client/firefox: LTO Updates

Force LTO with USE=pgo

LTO now comes from CFLAGS, meaning that the REQUIRED_USE
previously enforcing this was removed in favour of
`eerror`. Instead we will force LTO even if it's not detected
from CFLAGS if PGO is in use.

Drop USE=lto on 128 to bring it into line with 132.

Signed-off-by: Matt Jolly <kangie@gentoo.org>

3 files changed, 41 insertions, 25 deletions

diff --git a/www-client/firefox/firefox-128.4.0-r1.ebuild b/www-client/firefox/firefox-128.4.0-r1.ebuild
index 1c04269f3aa9..3dbba65f6d4b 100644
--- a/www-client/firefox/firefox-128.4.0-r1.ebuild
+++ b/www-client/firefox/firefox-128.4.0-r1.ebuild
@@ -64,7 +64,7 @@ S="${WORKDIR}/${PN}-${PV%_*}"
 LICENSE="MPL-2.0 GPL-2 LGPL-2.1"
 KEYWORDS="amd64 ~arm64 ~ppc64 ~riscv ~x86"
 
-IUSE="clang dbus debug eme-free hardened hwaccel jack +jumbo-build libproxy lto openh264 pgo"
+IUSE="clang dbus debug eme-free hardened hwaccel jack +jumbo-build libproxy openh264 pgo"
 IUSE+=" pulseaudio selinux sndio +system-av1 +system-harfbuzz +system-icu +system-jpeg"
 IUSE+=" +system-libevent +system-libvpx system-png +system-webp +telemetry wayland wifi +X"
 
@@ -73,7 +73,6 @@ IUSE+=" +gmp-autoupdate gnome-shell"
 
 REQUIRED_USE="|| ( X wayland )
 	debug? ( !system-av1 )
-	pgo? ( lto )
 	wayland? ( dbus )
 	wifi? ( dbus )"
 
@@ -441,7 +440,7 @@ pkg_pretend() {
 		fi
 
 		# Ensure we have enough disk space to compile
-		if use pgo || use lto || use debug ; then
+		if use pgo || tc-is-lto || use debug ; then
 			CHECKREQS_DISK_BUILD="13500M"
 		else
 			CHECKREQS_DISK_BUILD="6600M"
@@ -452,15 +451,34 @@ pkg_pretend() {
 }
 
 pkg_setup() {
+
+	# Get LTO from environment; export after this phase for use in src_configure (etc)
+	use_lto=no
+
 	if [[ ${MERGE_TYPE} != binary ]] ; then
+
+		if tc-is-lto; then
+			use_lto=yes
+			# LTO is handled via configure
+			# -Werror=lto-type-mismatch -Werror=odr are going to fail with GCC,
+			# bmo#1516758, bgo#942288
+			filter-lto
+			filter-flags -Werror=lto-type-mismatch -Werror=odr
+		fi
+
 		if use pgo ; then
+			if [[ ${use_lto} == "no" ]]; then
+				elog "Building ${PN} with USE=pgo requires LTO, however this was not detected in your environment."
+				elog "Forcing LTO, however it is recommended to enable LTO explicitly."
+				use_lto=yes
+			fi
 			if ! has userpriv ${FEATURES} ; then
 				eerror "Building ${PN} with USE=pgo and FEATURES=-userpriv is not supported!"
 			fi
 		fi
 
 		# Ensure we have enough disk space to compile
-		if use pgo || use lto || use debug ; then
+		if use pgo || [[ ${use_lto} == "yes" ]] || use debug ; then
 			CHECKREQS_DISK_BUILD="13500M"
 		else
 			CHECKREQS_DISK_BUILD="6400M"
@@ -471,7 +489,7 @@ pkg_setup() {
 		llvm-r1_pkg_setup
 		rust_pkg_setup
 
-		if use clang && use lto && tc-ld-is-lld ; then
+		if use clang && [[ ${use_lto} == "yes" ]] && tc-ld-is-lld ; then
 			local version_lld=$(ld.lld --version 2>/dev/null | awk '{ print $2 }')
 			[[ -n ${version_lld} ]] && version_lld=$(ver_cut 1 "${version_lld}")
 			[[ -z ${version_lld} ]] && die "Failed to read ld.lld version!"
@@ -485,7 +503,7 @@ pkg_setup() {
 				eerror "You will be unable to link ${CATEGORY}/${PN}. To proceed you have the following options:"
 				eerror "  - Manually switch rust version using 'eselect rust' to match used LLVM version"
 				eerror "  - Switch to dev-lang/rust[system-llvm] which will guarantee matching version"
-				eerror "  - Build ${CATEGORY}/${PN} without USE=lto"
+				eerror "  - Build ${CATEGORY}/${PN} without lto"
 				eerror "  - Rebuild lld with llvm that was used to build rust (may need to rebuild the whole "
 				eerror "    llvm/clang/lld/rust chain depending on your @world updates)"
 				die "LLVM version used by Rust (${version_llvm_rust}) does not match with ld.lld version (${version_lld})!"
@@ -546,6 +564,8 @@ pkg_setup() {
 		export LC_ALL=C
 	fi
 
+	export use_lto
+
 	CONFIG_CHECK="~SECCOMP"
 	WARNING_SECCOMP="CONFIG_SECCOMP not set! This system will be unable to play DRM-protected content."
 	linux-info_pkg_setup
@@ -569,7 +589,7 @@ src_unpack() {
 }
 
 src_prepare() {
-	if use lto; then
+	if [[ ${use_lto} == "yes" ]]; then
 		rm -v "${WORKDIR}"/firefox-patches/*-LTO-Only-enable-LTO-*.patch || die
 	fi
 
@@ -899,13 +919,7 @@ src_configure() {
 		mozconfig_add_options_ac '+x11' --enable-default-toolkit=cairo-gtk3-x11-only
 	fi
 
-	# LTO is handled via configure.
-	# -Werror=lto-type-mismatch -Werror=odr are going to fail with GCC,
-	# bmo#1516758, bgo#942288
-	filter-lto
-	filter-flags -Werror=lto-type-mismatch -Werror=odr
-
-	if use lto ; then
+	if [[ ${use_lto} == "yes" ]]; then
 		if use clang ; then
 			# Upstream only supports lld or mold when using clang.
 			if tc-ld-is-mold ; then
@@ -1080,7 +1094,7 @@ src_configure() {
 src_compile() {
 	local virtx_cmd=
 
-	if tc-ld-is-mold && use lto; then
+	if tc-ld-is-mold && [[ ${use_lto} == "yes" ]]; then
 		# increase ulimit with mold+lto, bugs #892641, #907485
 		if ! ulimit -n 16384 1>/dev/null 2>&1 ; then
 			ewarn "Unable to modify ulimits - building with mold+lto might fail due to low ulimit -n resources."
diff --git a/www-client/firefox/firefox-132.0-r1.ebuild b/www-client/firefox/firefox-132.0-r1.ebuild
index 858c6586a808..42cdfb7c9604 100644
--- a/www-client/firefox/firefox-132.0-r1.ebuild
+++ b/www-client/firefox/firefox-132.0-r1.ebuild
@@ -472,9 +472,10 @@ pkg_setup() {
 		fi
 
 		if use pgo ; then
-			if [[ ${use_lto} == "no" ]]; then
-				eerror "Building ${PN} with USE=pgo requires LTO!"
-				die "Please fix your CFLAGS/CXXFLAGS."
+			if [[ ${use_lto} == "no" ]] ; then
+				elog "Building ${PN} with USE=pgo requires LTO, however this was not detected in your environment."
+				elog "Forcing LTO, however it is recommended to enable LTO explicitly."
+				use_lto=yes
 			fi
 			if ! has userpriv ${FEATURES} ; then
 				eerror "Building ${PN} with USE=pgo and FEATURES=-userpriv is not supported!"
@@ -583,7 +584,7 @@ src_unpack() {
 }
 
 src_prepare() {
-	if [[ ${use_lto} = "yes" ]]; then
+	if [[ ${use_lto} == "yes" ]]; then
 		rm -v "${WORKDIR}"/firefox-patches/*-LTO-Only-enable-LTO-*.patch || die
 	fi
 
@@ -902,7 +903,7 @@ src_configure() {
 		mozconfig_add_options_ac '+x11' --enable-default-toolkit=cairo-gtk3-x11-only
 	fi
 
-	if [[ ${use_lto} = "yes" ]] ; then
+	if [[ ${use_lto} == "yes" ]] ; then
 		if use clang ; then
 			# Upstream only supports lld or mold when using clang.
 			if tc-ld-is-mold ; then
diff --git a/www-client/firefox/firefox-132.0.1-r1.ebuild b/www-client/firefox/firefox-132.0.1-r1.ebuild
index c767c09e4a2a..56c448010e00 100644
--- a/www-client/firefox/firefox-132.0.1-r1.ebuild
+++ b/www-client/firefox/firefox-132.0.1-r1.ebuild
@@ -470,9 +470,10 @@ pkg_setup() {
 		fi
 
 		if use pgo ; then
-			if [[ ${use_lto} == "no" ]]; then
-				eerror "Building ${PN} with USE=pgo requires LTO!"
-				die "Please fix your CFLAGS/CXXFLAGS."
+			if [[ ${use_lto} == "no" ]] ; then
+				elog "Building ${PN} with USE=pgo requires LTO, however this was not detected in your environment."
+				elog "Forcing LTO, however it is recommended to enable LTO explicitly."
+				use_lto=yes
 			fi
 			if ! has userpriv ${FEATURES} ; then
 				eerror "Building ${PN} with USE=pgo and FEATURES=-userpriv is not supported!"
@@ -581,7 +582,7 @@ src_unpack() {
 }
 
 src_prepare() {
-	if [[ ${use_lto} = "yes" ]]; then
+	if [[ ${use_lto} == "yes" ]]; then
 		rm -v "${WORKDIR}"/firefox-patches/*-LTO-Only-enable-LTO-*.patch || die
 	fi
 
@@ -900,7 +901,7 @@ src_configure() {
 		mozconfig_add_options_ac '+x11' --enable-default-toolkit=cairo-gtk3-x11-only
 	fi
 
-	if [[ ${use_lto} = "yes" ]] ; then
+	if [[ ${use_lto} == "yes" ]] ; then
 		if use clang ; then
 			# Upstream only supports lld or mold when using clang.
 			if tc-ld-is-mold ; then