diff --git a/ChangeLog b/ChangeLog
index 79ad079da..3796ae85f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2012-08-07 Peter Stephenson
+
+ * YAMAMOTO Takashi: 30599: Src/compat.c, Src/zsh.h: don't
+ use the replacement wcwidth if not ISO-10646 as the assumptions
+ it makes probably won't work.
+
2012-07-27 Peter Stephenson
* 30590: Doc/Makefile.in, Doc/.distfiles: work around problem
@@ -16467,5 +16473,5 @@
*****************************************************
* This is used by the shell to define $ZSH_PATCHLEVEL
-* $Revision: 1.5684 $
+* $Revision: 1.5685 $
*****************************************************
diff --git a/Src/compat.c b/Src/compat.c
index e36de3219..6d08dab94 100644
--- a/Src/compat.c
+++ b/Src/compat.c
@@ -630,7 +630,7 @@ strtoul(nptr, endptr, base)
#endif /* HAVE_STRTOUL */
/**/
-#ifdef BROKEN_WCWIDTH
+#if defined(BROKEN_WCWIDTH) && defined(__STDC_ISO_10646__)
/*
* This is an implementation of wcwidth() and wcswidth() (defined in
@@ -949,5 +949,5 @@ int mk_wcswidth_cjk(const wchar_t *pwcs, size_t n)
#endif /* 0 */
/**/
-#endif /* BROKEN_WCWIDTH */
+#endif /* BROKEN_WCWIDTH && __STDC_ISO_10646__ */
diff --git a/Src/zsh.h b/Src/zsh.h
index cc3a67008..afe22f059 100644
--- a/Src/zsh.h
+++ b/Src/zsh.h
@@ -2678,7 +2678,7 @@ typedef wint_t convchar_t;
#define MB_METASTRWIDTH(str) mb_metastrlen(str, 1)
#define MB_METASTRLEN2(str, widthp) mb_metastrlen(str, widthp)
-#ifdef BROKEN_WCWIDTH
+#if defined(BROKEN_WCWIDTH) && defined(__STDC_ISO_10646__)
#define WCWIDTH(wc) mk_wcwidth(wc)
#else
#define WCWIDTH(wc) wcwidth(wc)