Strip darwin C-ext to remove paths to C files

... which are only valid in the build environment.

Author: larskanis

ext/extconf.rb

@@ -330,3 +330,20 @@ module PG
 create_header()
 create_makefile( "pg_ext" )
 
+if gem_platform
+	# exercise the strip command on native binary gems
+	# This approach borrowed from
+	# https://github.com/rake-compiler/rake-compiler-dock/blob/38066d479050f4fdb3956469255b35a05e5949ef/test/rcd_test/ext/mri/extconf.rb#L97C1-L110C42
+	strip_tool = RbConfig::CONFIG['STRIP']
+	strip_tool += ' -x' if RUBY_PLATFORM =~ /darwin/
+		File.open('Makefile.new', 'w') do |o|
+		o.puts 'hijack: all strip'
+		o.puts
+		o.write(File.read('Makefile'))
+		o.puts
+		o.puts 'strip: $(DLLIB)'
+		o.puts "\t$(ECHO) Stripping $(DLLIB)"
+		o.puts "\t$(Q) #{strip_tool} $(DLLIB)"
+	end
+	File.rename('Makefile.new', 'Makefile')
+end