buildMozillaMach: Add RELRHACK_LINKER patch (#401323)

pkgs/applications/networking/browsers/firefox/build-fix-RELRHACK_LINKER-setting-when-linker-name-i.patch

@@ -0,0 +1,57 @@
+From 45d40b3eeb393051bd3a49feebcefe39dc6e4e93 Mon Sep 17 00:00:00 2001
+From: Peter Collingbourne <pcc@google.com>
+Date: Wed, 23 Apr 2025 21:13:38 -0700
+Subject: [PATCH] build: fix RELRHACK_LINKER setting when linker name is target
+ triple prefixed
+
+RELRHACK_LINKER is used as the name of a binary installed in a
+directory specified with -B to override the linker. Both Clang and
+GCC will only look for a binary named "ld" (or "ld.$fuse_ld_setting"
+if -fuse-ld= is specified) in the -B directories, which means that
+if the linker name does not follow this pattern, for example if it
+is named $target_triple-ld", the relrhack linker will not be found,
+the compiler will use the normal linker and the link will fail. To fix
+this problem, use the correct pattern to name the relrhack executable.
+---
+ toolkit/moz.configure | 16 ++++++++--------
+ 1 file changed, 8 insertions(+), 8 deletions(-)
+
+diff --git a/toolkit/moz.configure b/toolkit/moz.configure
+index 6c47287a5b..1a9c368e5e 100644
+--- a/toolkit/moz.configure
++++ b/toolkit/moz.configure
+@@ -1843,23 +1843,23 @@ with only_when("--enable-compile-environment"):
+     use_relrhack = depends(which_elf_hack)(lambda x: x == "relr")
+     set_config("RELRHACK", True, when=use_relrhack)
+ 
+-    @depends(c_compiler, linker_ldflags, when=use_relrhack)
+-    def relrhack_real_linker(c_compiler, linker_ldflags):
++    @depends(linker_ldflags, when=use_relrhack)
++    def relrhack_linker(linker_ldflags):
+         ld = "ld"
+         for flag in linker_ldflags:
+             if flag.startswith("-fuse-ld="):
+                 ld = "ld." + flag[len("-fuse-ld=") :]
++        return ld
++
++    set_config("RELRHACK_LINKER", relrhack_linker)
++
++    @depends(c_compiler, relrhack_linker, when=use_relrhack)
++    def relrhack_real_linker(c_compiler, ld):
+         ld = check_cmd_output(
+             c_compiler.compiler, f"--print-prog-name={ld}", *c_compiler.flags
+         )
+         return ld.rstrip()
+ 
+-    @depends(relrhack_real_linker, when=use_relrhack)
+-    def relrhack_linker(ld):
+-        return os.path.basename(ld)
+-
+-    set_config("RELRHACK_LINKER", relrhack_linker)
+-
+     std_filesystem = host_cxx_compiler.try_run(
+         header="#include <filesystem>",
+         body='auto foo = std::filesystem::absolute("");',
+-- 
+2.49.0.805.g082f7c87e0-goog
+

pkgs/applications/networking/browsers/firefox/common.nix

@@ -357,6 +357,10 @@ buildStdenv.mkDerivation {
       # Fix for missing vector header on macOS
       # https://bugzilla.mozilla.org/show_bug.cgi?id=1939405
       ./firefox-mac-missing-vector-header.patch
+
+      # https://bugzilla.mozilla.org/show_bug.cgi?id=1962497
+      # https://phabricator.services.mozilla.com/D246545
+      ./build-fix-RELRHACK_LINKER-setting-when-linker-name-i.patch
     ]
     ++ extraPatches;