From f8a28f990a8ec421cbda2a4f55ec587f27d5d2b4 Mon Sep 17 00:00:00 2001
From: Mike Hommey <mh+mozilla@glandium.org>
Date: Thu, 25 May 2023 01:49:06 +0000
Subject: [PATCH] Bug 1834678 - Change the llvm-config trick for
 cross-compilation. r=gfx-reviewers,gw

Contrary to ld64, lld doesn't ignore libraries it's given on the command
line, and -lLLVM-14 ends up as a link error when using lld.

So instead of relying on the flags llvm-config outputs to be kind of
ignored, we replace them at the source by wrapping llvm-config itself.

Differential Revision: https://phabricator.services.mozilla.com/D178900
---
 gfx/wr/ci-scripts/etc/wr-darwin.meson                | 12 +-----------
 .../scripts/misc/wr-macos-cross-build-setup.sh       |  5 ++++-
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/gfx/wr/ci-scripts/etc/wr-darwin.meson b/gfx/wr/ci-scripts/etc/wr-darwin.meson
index 54499822254f..e6efc7deb13f 100644
--- a/gfx/wr/ci-scripts/etc/wr-darwin.meson
+++ b/gfx/wr/ci-scripts/etc/wr-darwin.meson
@@ -1,15 +1,5 @@
 [binaries]
-llvm-config = '/builds/worker/fetches/clang/bin/llvm-config'
-
-[properties]
-# When linking `libOSMesa.dylib` Meson uses options provided by `llvm-config`.
-# The binary for `llvm-config` in Firefox CI comes from a native Linux clang,
-# which gives the link options for the Linux libLLVM-11.so in the Linux clang.
-# However, we want to link against a native macOS clang's libLLVM.dylib, which
-# we have available in a separate directory.
-# Meson will still have -lLLVM-11 on the command line, but the linker will
-# only warn that it has the wrong format (because it's not for macOS).
-cpp_link_args = ['-L/builds/worker/fetches/clang-mac/clang/lib', '-lLLVM']
+llvm-config = '/builds/worker/fetches/clang-mac/clang/bin/llvm-config'
 
 [host_machine]
 system = 'darwin'
diff --git a/taskcluster/scripts/misc/wr-macos-cross-build-setup.sh b/taskcluster/scripts/misc/wr-macos-cross-build-setup.sh
index 4edba33e5e14..faca8d2142ea 100755
--- a/taskcluster/scripts/misc/wr-macos-cross-build-setup.sh
+++ b/taskcluster/scripts/misc/wr-macos-cross-build-setup.sh
@@ -29,7 +29,10 @@ END_PKGCONFIG_WRAPPER
 chmod +x "${TARGET_TRIPLE}-pkg-config"
 popd
 
-export PATH="${MOZ_FETCHES_DIR}/rustc/bin:${MOZ_FETCHES_DIR}/cctools/bin:${MOZ_FETCHES_DIR}/clang/bin:${MOZ_FETCHES_DIR}/wrench-deps/meson:${PATH}"
+[ -d "${MOZ_FETCHES_DIR}/clang-mac/clang" ] && cat > ${MOZ_FETCHES_DIR}/clang-mac/clang/bin/llvm-config <<EOF_LLVM_CONFIG
+#!/bin/sh
+${MOZ_FETCHES_DIR}/clang/bin/llvm-config "\$@" | sed 's,${MOZ_FETCHES_DIR}/clang,${MOZ_FETCHES_DIR}/clang-mac/clang,g;s,-lLLVM-[0-9]\+,-lLLVM,g'
+EOF_LLVM_CONFIG
 
 # The x86_64-darwin11-ld linker from cctools requires libraries provided
 # by clang, so we need to set LD_LIBRARY_PATH for that to work.