Fix use of compiler command in linker script.

Author: aardvark179

lib/cext/linker.rb

@@ -76,7 +76,7 @@ def self.compile_if_needed(files)
       files.map do |file|
         if file.end_with?('.c')
           objfile = "#{File.dirname(file)}/#{File.basename(file, '.*')}.#{RbConfig::CONFIG['OBJEXT']}"
-          compile = RbConfig::CONFIG['COMPILE_C'].gsub('$<', file).gsub('$@', objfile)
+          compile = RbConfig::CONFIG['TRUFFLE_RAW_COMPILE_C'].gsub('$<', file).gsub('$@', objfile)
           compile = compile.sub('$(INCFLAGS)', @incflags.join(' '))
           compile = compile.sub('$(COUTFLAG)', '')
           if system(compile)

lib/truffle/rbconfig-for-mkmf.rb

@@ -147,6 +147,7 @@
   cxx_flags = "$(INCFLAGS) $(CPPFLAGS) $(CXXFLAGS) $(COUTFLAG) -xc++"
   opt_command = "#{opt} #{opt_passes} $@ -o $@"
 
+  mkconfig["TRUFFLE_RAW_COMPILE_C"] = for_file.call("$(CC)", c_flags, opt_command)
   mkconfig['COMPILE_C']   = with_conditional_preprocessing.call(
     for_pipe.call("$(CC)", c_flags, opt_command),
     for_file.call("$(CC)", c_flags, opt_command))