www-client/chromium: do a better job of forcing Clang

When enabling the Rust eclass, we started directly using
`llvm-r1_pkg_setup`, assuming that this combination would be
sufficicent, however due to forcing `CC` (etc) to variations
on `${CHOST}-clang" _before_ calling `llvm-r1_pkg_setup`,
these would always be forced to the newest version in
`PATH` instead of the one matching `LLVM_SLOT` due to
the eclass fixing the version before doing any `PATH`
manipulation.

To ensure a consistent build environment, we will:

1. Explicitly include `-${LLVM_SLOT}` in `CC`, `CPP`, `CXX`
2. Set these variables (and `AR` and `NM`) after `llvm-r1_pkg_setup`
   has done its PATH manipulation.

Bug: https://bugs.gentoo.org/935689
Signed-off-by: Matt Jolly <kangie@gentoo.org>

4 files changed, 32 insertions, 36 deletions

diff --git a/www-client/chromium/chromium-130.0.6723.116-r1.ebuild b/www-client/chromium/chromium-130.0.6723.116-r1.ebuild
index 4c3745081087..7d3695283e2d 100644
--- a/www-client/chromium/chromium-130.0.6723.116-r1.ebuild
+++ b/www-client/chromium/chromium-130.0.6723.116-r1.ebuild
@@ -50,7 +50,6 @@ if [[ ${SLOT} != "0/dev" ]]; then
 	KEYWORDS="~amd64 ~arm64 ~ppc64"
 fi
 
-
 IUSE_SYSTEM_LIBS="+system-harfbuzz +system-icu +system-png +system-zstd"
 IUSE="+X ${IUSE_SYSTEM_LIBS} bindist cups debug ffmpeg-chromium gtk4 +hangouts headless kerberos +official pax-kernel pgo +proprietary-codecs pulseaudio"
 IUSE+=" qt5 qt6 +screencast selinux test +vaapi +wayland +widevine cpu_flags_ppc_vsx3"
@@ -309,24 +308,21 @@ pkg_setup() {
 			die "Please switch to a different linker."
 		fi
 
-		# We're forcing Clang here. User choice is respected via llvm_slot_# USE flags.
+		llvm-r1_pkg_setup
+		rust_pkg_setup
+
+		# Forcing clang; respect llvm_slot_x to enable selection of impl from LLVM_COMPAT
 		AR=llvm-ar
-		CPP="${CHOST}-clang++ -E"
+		CPP="${CHOST}-clang++-${LLVM_SLOT} -E"
 		NM=llvm-nm
-		CC=${CHOST}-clang
-		CXX=${CHOST}-clang++
+		CC="${CHOST}-clang-${LLVM_SLOT}"
+		CXX="${CHOST}-clang++-${LLVM_SLOT}"
 
 		if tc-is-cross-compiler; then
 			use pgo && die "The pgo USE flag cannot be used when cross-compiling"
-			CPP="${CBUILD}-clang++ -E"
+			CPP="${CBUILD}-clang++-${LLVM_SLOT} -E"
 		fi
 
-		llvm-r1_pkg_setup
-		rust_pkg_setup
-
-		einfo "Using LLVM/Clang slot ${LLVM_SLOT} to build"
-		einfo "Using Rust slot ${RUST_SLOT}, ${RUST_TYPE} to build"
-
 		# I hate doing this but upstream Rust have yet to come up with a better solution for
 		# us poor packagers. Required for Split LTO units, which are required for CFI.
 		export RUSTC_BOOTSTRAP=1
diff --git a/www-client/chromium/chromium-131.0.6778.85.ebuild b/www-client/chromium/chromium-131.0.6778.85.ebuild
index d33fbf3daff5..2cf96bc2284c 100644
--- a/www-client/chromium/chromium-131.0.6778.85.ebuild
+++ b/www-client/chromium/chromium-131.0.6778.85.ebuild
@@ -311,21 +311,21 @@ pkg_setup() {
 			die "Please switch to a different linker."
 		fi
 
-		# Forcing clang; user choice respected by llvm_slot_x USE
+		llvm-r1_pkg_setup
+		rust_pkg_setup
+
+		# Forcing clang; respect llvm_slot_x to enable selection of impl from LLVM_COMPAT
 		AR=llvm-ar
-		CPP="${CHOST}-clang++ -E"
+		CPP="${CHOST}-clang++-${LLVM_SLOT} -E"
 		NM=llvm-nm
-		CC=${CHOST}-clang
-		CXX=${CHOST}-clang++
+		CC="${CHOST}-clang-${LLVM_SLOT}"
+		CXX="${CHOST}-clang++-${LLVM_SLOT}"
 
 		if tc-is-cross-compiler; then
 			use pgo && die "The pgo USE flag cannot be used when cross-compiling"
-			CPP="${CBUILD}-clang++ -E"
+			CPP="${CBUILD}-clang++-${LLVM_SLOT} -E"
 		fi
 
-		llvm-r1_pkg_setup
-		rust_pkg_setup
-
 		# I hate doing this but upstream Rust have yet to come up with a better solution for
 		# us poor packagers. Required for Split LTO units, which are required for CFI.
 		export RUSTC_BOOTSTRAP=1
diff --git a/www-client/chromium/chromium-132.0.6834.15.ebuild b/www-client/chromium/chromium-132.0.6834.15.ebuild
index aa8e823dc2a0..d2ff0ec11a6d 100644
--- a/www-client/chromium/chromium-132.0.6834.15.ebuild
+++ b/www-client/chromium/chromium-132.0.6834.15.ebuild
@@ -310,21 +310,21 @@ pkg_setup() {
 			die "Please switch to a different linker."
 		fi
 
-		# Forcing clang; user choice respected by llvm_slot_x USE
+		llvm-r1_pkg_setup
+		rust_pkg_setup
+
+		# Forcing clang; respect llvm_slot_x to enable selection of impl from LLVM_COMPAT
 		AR=llvm-ar
-		CPP="${CHOST}-clang++ -E"
+		CPP="${CHOST}-clang++-${LLVM_SLOT} -E"
 		NM=llvm-nm
-		CC=${CHOST}-clang
-		CXX=${CHOST}-clang++
+		CC="${CHOST}-clang-${LLVM_SLOT}"
+		CXX="${CHOST}-clang++-${LLVM_SLOT}"
 
 		if tc-is-cross-compiler; then
 			use pgo && die "The pgo USE flag cannot be used when cross-compiling"
-			CPP="${CBUILD}-clang++ -E"
+			CPP="${CBUILD}-clang++-${LLVM_SLOT} -E"
 		fi
 
-		llvm-r1_pkg_setup
-		rust_pkg_setup
-
 		# I hate doing this but upstream Rust have yet to come up with a better solution for
 		# us poor packagers. Required for Split LTO units, which are required for CFI.
 		export RUSTC_BOOTSTRAP=1
diff --git a/www-client/chromium/chromium-133.0.6847.2.ebuild b/www-client/chromium/chromium-133.0.6847.2.ebuild
index 455597b1a1c8..c74866a48601 100644
--- a/www-client/chromium/chromium-133.0.6847.2.ebuild
+++ b/www-client/chromium/chromium-133.0.6847.2.ebuild
@@ -319,21 +319,21 @@ pkg_setup() {
 			die "Please switch to a different linker."
 		fi
 
-		# Forcing clang; user choice respected by llvm_slot_x USE
+		llvm-r1_pkg_setup
+		rust_pkg_setup
+
+		# Forcing clang; respect llvm_slot_x to enable selection of impl from LLVM_COMPAT
 		AR=llvm-ar
-		CPP="${CHOST}-clang++ -E"
+		CPP="${CHOST}-clang++-${LLVM_SLOT} -E"
 		NM=llvm-nm
-		CC=${CHOST}-clang
-		CXX=${CHOST}-clang++
+		CC="${CHOST}-clang-${LLVM_SLOT}"
+		CXX="${CHOST}-clang++-${LLVM_SLOT}"
 
 		if tc-is-cross-compiler; then
 			use pgo && die "The pgo USE flag cannot be used when cross-compiling"
-			CPP="${CBUILD}-clang++ -E"
+			CPP="${CBUILD}-clang++-${LLVM_SLOT} -E"
 		fi
 
-		llvm-r1_pkg_setup
-		rust_pkg_setup
-
 		# I hate doing this but upstream Rust have yet to come up with a better solution for
 		# us poor packagers. Required for Split LTO units, which are required for CFI.
 		export RUSTC_BOOTSTRAP=1