From 5feb40015695ca27cd3ca51a7c09ca1787fd4483 Mon Sep 17 00:00:00 2001
From: Bruno Haible <bruno@clisp.org>
Date: Fri, 22 Dec 2006 16:27:26 +0000
Subject: [PATCH] Add comments.

---
 lib/wctype_.h | 16 +++++++++++++---
 m4/wctype.m4  |  2 ++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/lib/wctype_.h b/lib/wctype_.h
index 11efbbb558..77a68143c5 100644
--- a/lib/wctype_.h
+++ b/lib/wctype_.h
@@ -18,13 +18,19 @@
 
 /* Written by Bruno Haible and Paul Eggert.  */
 
-/* iswctype, towctrans, towlower, towupper, wctrans, wctype,
-   wctrans_t, and wctype_t are not yet implemented.  */
+/*
+ * ISO C 99 <wctype.h> for platforms that lack it.
+ * <http://www.opengroup.org/susv3xbd/wctype.h.html>
+ *
+ * iswctype, towctrans, towlower, towupper, wctrans, wctype,
+ * wctrans_t, and wctype_t are not yet implemented.
+ */
 
 #ifndef _GL_WCTYPE_H
 #define _GL_WCTYPE_H
 
-/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
+/* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>.
+   Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
    <wchar.h>.
    BSD/OS 4.1 has a bug: <stdio.h> and <time.h> must be included before
    <wchar.h>.  */
@@ -32,10 +38,14 @@
 #include <time.h>
 #include <wchar.h>
 
+/* Include the original <wctype.h> if it exists.
+   BeOS 5 has the functions but no <wctype.h>.  */
 #if @HAVE_WCTYPE_H@
 # include @ABSOLUTE_WCTYPE_H@
 #endif
 
+/* IRIX 5.3 has a bug: its isw* macros reference an undefined variable
+   _ctmp_.  */
 #if @HAVE_WCTYPE_CTMP_BUG@
 static wint_t _ctmp_;
 #endif
diff --git a/m4/wctype.m4 b/m4/wctype.m4
index 4fd392e97c..357c7a5f98 100644
--- a/m4/wctype.m4
+++ b/m4/wctype.m4
@@ -27,6 +27,8 @@ AC_DEFUN([gl_WCTYPE_H],
   WCTYPE_H=wctype.h
   HAVE_WCTYPE_CTMP_BUG=0
   if test $ac_cv_header_wctype_h = yes; then
+    dnl IRIX 5.3 has a bug: its isw* macros reference an undefined variable
+    dnl _ctmp_. Test against this bug.
     AC_CACHE_CHECK([whether wctype macros need _ctmp_ declared],
       [gl_cv_wctype_ctmp_bug],
       [gl_cv_wctype_ctmp_bug=no
-- 
2.30.2