diff --git a/pkgs/gcc/gcc.yaml b/pkgs/gcc/gcc.yaml
index 8710ab881..48c667af5 100644
--- a/pkgs/gcc/gcc.yaml
+++ b/pkgs/gcc/gcc.yaml
@@ -6,10 +6,17 @@ dependencies:
 
 defaults:
   relocatable: false
+  version: 4.9.2
+
+when version == '4.9.2':
+    sources:
+    - key: tar.bz2:eaqmtauvqvvkcp62b4xtur4ujedvp7be
+      url: http://ftpmirror.gnu.org/gcc/gcc-4.9.2/gcc-4.9.2.tar.bz2
+when version == '5.1.0':
+    sources:
+    - key: tar.bz2:w7np36e4xmhcamz5x5nvgsjrtlqg4pi2
+      url: http://ftpmirror.gnu.org/gcc/gcc-5.1.0/gcc-5.1.0.tar.bz2
 
-sources:
-- key: tar.bz2:eaqmtauvqvvkcp62b4xtur4ujedvp7be
-  url: http://ftpmirror.gnu.org/gcc/gcc-4.9.2/gcc-4.9.2.tar.bz2
 
 build_stages:
   # Make gcc automatically embed RPATH to the proper libstdc++, libgfortran,