From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Cheng Zhao <zcbenz@gmail.com>
Date: Tue, 2 Aug 2022 11:53:00 +0900
Subject: fix: link with @loader_path/libffmpeg.dylib

Submitted to https://chromium-review.googlesource.com/c/chromium/third_party/ffmpeg/+/3803946.

When building with `is_component_build=false is_component_ffmpeg=true`,
we must manually instruct executables to link with the ffmpeg.dylib,
which is generated at the @loader_path, where for most targets is the
out/{Release,Debug} dir.

Using @rpath is wrong because the @rpath of most targets does not
include the out dir, and the linker won't be able to find ffmpeg.dylib
because of so.

diff --git a/BUILD.gn b/BUILD.gn
index 0ac39bfbd05f56c5601a231249f1d9286d7d8da7..1bc23f7fa8ddcccc543d23b5353326df58475a87 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -448,7 +448,7 @@ if (is_component_ffmpeg) {
 
     if (!is_component_build) {
       if (is_mac) {
-        ldflags += [ "-Wl,-install_name,@rpath/libffmpeg.dylib" ]
+        ldflags += [ "-Wl,-install_name,@loader_path/libffmpeg.dylib" ]
       } else if (is_linux) {
         all_dependent_configs =
             [ "//build/config/gcc:rpath_for_built_shared_libraries" ]