"Error: key not found: :core2" on Travis-CI about legacy-linuxbrew HOT 1 CLOSED

diff --git a/Library/Homebrew/os/linux/hardware.rb b/Library/Homebrew/os/linux/hardware.rb
index 39ca96a..f6d88e7 100644
--- a/Library/Homebrew/os/linux/hardware.rb
+++ b/Library/Homebrew/os/linux/hardware.rb
@@ -1,5 +1,9 @@
 module LinuxCPUs
-  OPTIMIZATION_FLAGS = {}.freeze
+  OPTIMIZATION_FLAGS = {
+    :penryn => '-march=core2 -msse4.1',
+    :core2 => '-march=core2',
+    :core => '-march=prescott',
+  }.freeze
   def optimization_flags; OPTIMIZATION_FLAGS; end

   # Linux supports x86 only, and universal archs do not apply