1 files changed, 4 insertions, 0 deletions
diff --git a/common.mk b/common.mk
index 9520cbf34d..62c8e4871f 100644
--- a/common.mk
+++ b/common.mk
@@ -17,6 +17,10 @@ RUBYLIB       = $(PATH_SEPARATOR)
 RUBYOPT       = -
 RUN_OPTS      = --disable-gems
 
+GEM_HOME =
+GEM_PATH =
+GEM_VENDOR =
+
 SPEC_GIT_BASE = git://github.com/ruby
 MSPEC_GIT_URL = $(SPEC_GIT_BASE)/mspec.git
 RUBYSPEC_GIT_URL = $(SPEC_GIT_BASE)/rubyspec.git