diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index d11aeefd3790ebcaeed5b32c1d7b2804d8c50222..8c4614a3dd69373ec511a58d6966584896d64548 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -322,7 +322,10 @@ protected
         raise
       end
     end
-  rescue
+  rescue SystemCallError
+    # usually because exec could not be find the command that was requested
+    raise
+  rescue 
     raise BuildError.new(cmd, args, $?)
   end