diff --git a/Library/Homebrew/cmd/--env.rb b/Library/Homebrew/cmd/--env.rb
index 64838a5c01..6807bf3495 100644
--- a/Library/Homebrew/cmd/--env.rb
+++ b/Library/Homebrew/cmd/--env.rb
@@ -16,8 +16,9 @@ module Homebrew extend self
   end
 
   def build_env_keys env
-    %w[ CC CXX LD CFLAGS CXXFLAGS CPPFLAGS LDFLAGS MACOSX_DEPLOYMENT_TARGET
-      MAKEFLAGS PKG_CONFIG_PATH HOMEBREW_BUILD_FROM_SOURCE HOMEBREW_DEBUG
+    %w[ CC CXX LD CFLAGS CXXFLAGS CPPFLAGS CMAKE_PREFIX_PATH
+      CMAKE_INBLUDE_PATH LDFLAGS MACOSX_DEPLOYMENT_TARGET MAKEFLAGS
+      PKG_CONFIG_PATH HOMEBREW_BUILD_FROM_SOURCE HOMEBREW_DEBUG
       HOMEBREW_MAKE_JOBS HOMEBREW_VERBOSE HOMEBREW_USE_CLANG HOMEBREW_USE_GCC
       HOMEBREW_USE_LLVM HOMEBREW_SVN ].select{ |key| env[key] }
   end