fix(native_comp): add option to enable/disable relinking *.eln files

Relinking the /usr/local/lib/gcc/10/libgcc_s.1.dylib shared library
within bundled *.eln files is still causing issues with code signing, so
I'm adding an option to toggle *.eln file re-linking on/off, with it on
by default.

build-emacs-for-macos

@@ -107,7 +107,7 @@ class Build
     handle_native_lisp(app)
     add_cli_helper(app)
 
-    LibEmbedder.new(app, brew_dir, extra_libs).embed
+    LibEmbedder.new(app, brew_dir, extra_libs, optsion[:relink_eln]).embed
     GccLibEmbedder.new(app, gcc_info).embed if options[:native_comp]
 
     archive_build(build_dir) if options[:archive]
@@ -157,11 +157,22 @@ class Build
   end
 
   def extra_libs
-    @extra_libs ||= [
+    return @extra_libs if @extra_libs
+
+    libs = [
       File.join(brew_dir, 'opt/expat/lib/libexpat.1.dylib'),
       File.join(brew_dir, 'opt/libiconv/lib/libiconv.2.dylib'),
       File.join(brew_dir, 'opt/zlib/lib/libz.1.dylib')
     ]
+
+    if options[:native_comp]
+      libgcc_s = File.join(
+        brew_dir, 'lib', 'gcc', gcc_info.major_version, 'libgcc_s.1.dylib'
+      )
+      libs << libgcc_s if File.exist?(libgcc_s)
+    end
+
+    @extra_libs = libs
   end
 
   def download_tarball(sha)
@@ -755,7 +766,7 @@ class LibEmbedder < AbstractEmbedder
   attr_reader :lib_source
   attr_reader :extra_libs
 
-  def initialize(app, lib_source, extra_libs = [])
+  def initialize(app, lib_source, extra_libs = [], embed_eln_files = true)
     super(app)
 
     @lib_source = lib_source
@@ -777,7 +788,7 @@ class LibEmbedder < AbstractEmbedder
         rel_path = Pathname.new(lib_dir).relative_path_from(
           Pathname.new(File.dirname(binary))
         ).to_s
-        eln_files.each { |f| copy_libs(f, rel_path) }
+        eln_files.each { |f| copy_libs(f, rel_path) } if embed_eln_files
       end
     end
   end
@@ -1086,6 +1097,12 @@ if __FILE__ == $PROGRAM_NAME
         cli_options[:native_full_aot] = v
       end
 
+      opts.on('--[no-]relink-eln-files',
+              'Enable/disable re-linking shared libraries in bundled *.eln ' \
+              'files (default: enabled)') do |v|
+        cli_options[:relink_eln] = v
+      end
+
       opts.on('--[no-]rsvg',
               'Enable/disable SVG image support via librsvg ' \
               '(default: enabled)') do |v|