diff --git a/ChangeLog b/ChangeLog
index eef9b690b7..5aed647b40 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Sep 16 08:57:52 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* configure.in (strict_warnflags): separate strict flags from
+	  warnflags only for core.  [ruby-dev:46105]
+
 Sun Sep 16 08:16:05 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* .editorconfig: add.  [ruby-core:47548] [Feature #7030]
diff --git a/Makefile.in b/Makefile.in
index 309e39e2dd..8087065bea 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -56,7 +56,7 @@ CFLAGS = @CFLAGS@ $(ARCH_FLAG)
 cflags = @cflags@
 optflags = @optflags@
 debugflags = @debugflags@
-warnflags = @warnflags@
+warnflags = @warnflags@ @strict_warnflags@
 INCFLAGS = -I. -I$(arch_hdrdir) -I$(hdrdir) -I$(srcdir)
 XCFLAGS = @XCFLAGS@
 CPPFLAGS = @CPPFLAGS@ $(INCFLAGS)
diff --git a/configure.in b/configure.in
index fd374b928a..a5a5a21ae9 100644
--- a/configure.in
+++ b/configure.in
@@ -630,8 +630,7 @@ if test "$GCC" = yes; then
     [
       # ANSI (no XCFLAGS because this is C only)
       RUBY_TRY_CFLAGS(-ansi -std=iso9899:199409, [
-        RUBY_APPEND_OPTION(warnflags, -ansi -std=iso9899:199409)
-        RUBY_APPEND_OPTION(rb_cv_warnflags, -ansi -std=iso9899:199409)
+        RUBY_APPEND_OPTION(strict_warnflags, -ansi -std=iso9899:199409)
       ])
     ])
 
@@ -2956,6 +2955,7 @@ AC_SUBST(cxxflags, ["$orig_cxxflags "'${optflags} ${debugflags} ${warnflags}'])d
 AC_SUBST(optflags)dnl
 AC_SUBST(debugflags)dnl
 AC_SUBST(warnflags)dnl
+AC_SUBST(strict_warnflags)dnl
 AC_SUBST(XCFLAGS)dnl
 AC_SUBST(XLDFLAGS)dnl
 AC_SUBST(EXTLDFLAGS)dnl