diff --git a/Library/ENV/4.3/cc b/Library/ENV/4.3/cc
index 2ce4bf73d5..c1adc56992 100755
--- a/Library/ENV/4.3/cc
+++ b/Library/ENV/4.3/cc
@@ -149,6 +149,9 @@ class Cmd
       "-fuse-linker-plugin"
       # clang doesn't support these flags
       args << arg unless tool =~ /^clang/
+    when "-Wno-deprecated-register"
+      # older gccs don't support these flags
+      args << arg unless tool =~ /^gcc-4.[02]/
     when /^-W[alp],/, /^-Wno-/
       args << arg
     when /^-W.*/