diff --git a/lib/rscons/builder.rb b/lib/rscons/builder.rb
index fe54565..95da69f 100644
--- a/lib/rscons/builder.rb
+++ b/lib/rscons/builder.rb
@@ -1,6 +1,6 @@
 module Rscons
   class Builder
-    def self.makes_object_file?(env, fname)
+    def self.produces?(env, suffix)
       false
     end
   end
diff --git a/lib/rscons/builders/cc.rb b/lib/rscons/builders/cc.rb
index d7af459..7b91cdf 100644
--- a/lib/rscons/builders/cc.rb
+++ b/lib/rscons/builders/cc.rb
@@ -8,10 +8,8 @@ module Rscons
       'CEXTS' => ['.c'],
     }
 
-    def self.makes_object_file?(env, fname)
-      env['CEXTS'].find do |cext|
-        fname =~ /#{cext}$/
-      end
+    def self.produces?(env, suffix)
+      suffix == env['OBJSUFFIX']
     end
 
     def run(env, target, source)
diff --git a/lib/rscons/builders/program.rb b/lib/rscons/builders/program.rb
index b457036..8eb60da 100644
--- a/lib/rscons/builders/program.rb
+++ b/lib/rscons/builders/program.rb
@@ -16,7 +16,7 @@ module Rscons
         if source =~ /#{env['OBJSUFFIX']}$/ or source =~ /#{env['LIBSUFFIX']}$/
           source
         else
-          builder_class = env.builders.values.find { |klass| klass.makes_object_file?(env, source) }
+          builder_class = env.builders.values.find { |klass| klass.produces?(env, env['OBJSUFFIX']) }
           if builder_class
             builder = builder_class.new
             builder.run(env, env.stem(source) + env['OBJSUFFIX'], source)