diff --git a/ChangeLog b/ChangeLog
index 37652f567f..d790a7cc19 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Nov 13 19:50:30 2001  WATANABE Hirofumi  <eban@ruby-lang.org>
+
+	* configure.in: do not override CC if set.
+
 Tue Nov 13 16:49:16 2001  Usaku Nakamura <usa@ruby-lang.org>
 
 	* win32/win32.c (mypopen): return error status instead of calling
diff --git a/configure.in b/configure.in
index 390daf410a..83a90037d9 100644
--- a/configure.in
+++ b/configure.in
@@ -11,14 +11,14 @@ AC_SUBST(TEENY)
 dnl checks for alternative programs
 AC_ARG_WITH(gcc, [--without-gcc             never use gcc], [
 	case $withval in
-	no)	CC=cc
+	no)	: ${CC=cc}
 		without_gcc=yes;;
-	yes)	CC=gcc
+	yes)	: ${CC=gcc}
 		without_gcc=no;;
 	*)	CC=$withval
 		without_gcc=$withval;;
 	esac], [
-	  CC=gcc
+	  : ${CC=gcc}
 	  without_gcc=no])
 dnl If the user switches compilers, we can't believe the cache
 if test ! -z "$ac_cv_prog_CC" -a ! -z "$CC" -a "$CC" != "$ac_cv_prog_CC"