1 files changed, 1 insertions, 1 deletions
diff --git a/main.c b/main.c
index e76228713f..0d0ec147cd 100644
--- a/main.c
+++ b/main.c
@@ -23,7 +23,7 @@
 #ifdef HAVE_LOCALE_H
 #include <locale.h>
 #endif
-#if RUBY_DEVEL && !defined RUBY_DEBUG_ENV
+#if defined RUBY_DEVEL && !defined RUBY_DEBUG_ENV
 # define RUBY_DEBUG_ENV 1
 #endif
 #if defined RUBY_DEBUG_ENV && !RUBY_DEBUG_ENV