1 files changed, 32 insertions, 2 deletions

diff --git a/gl/m4/wctype.m4 b/gl/m4/wctype.m4
index 7483c4f..6a1b6f0 100644
--- a/gl/m4/wctype.m4
+++ b/gl/m4/wctype.m4
@@ -1,6 +1,8 @@
+# wctype.m4 serial 2
+
 dnl A placeholder for ISO C99 <wctype.h>, for platforms that lack it.
 
-dnl Copyright (C) 2006, 2007 Free Software Foundation, Inc.
+dnl Copyright (C) 2006-2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -9,6 +11,7 @@ dnl Written by Paul Eggert.
 
 AC_DEFUN([gl_WCTYPE_H],
 [
+  AC_REQUIRE([AC_PROG_CC])
   AC_CHECK_FUNCS_ONCE([iswcntrl])
   if test $ac_cv_func_iswcntrl = yes; then
     HAVE_ISWCNTRL=1
@@ -30,7 +33,27 @@ AC_DEFUN([gl_WCTYPE_H],
   WCTYPE_H=wctype.h
   if test $ac_cv_header_wctype_h = yes; then
     if test $ac_cv_func_iswcntrl = yes; then
-      WCTYPE_H=
+      dnl Linux libc5 has an iswprint function that returns 0 for all arguments.
+      dnl The other functions are likely broken in the same way.
+      AC_CACHE_CHECK([whether iswcntrl works], [gl_cv_func_iswcntrl_works],
+        [
+          AC_TRY_RUN([#include <stddef.h>
+                      #include <stdio.h>
+                      #include <time.h>
+                      #include <wchar.h>
+                      #include <wctype.h>
+                      int main () { return iswprint ('x') == 0; }],
+            [gl_cv_func_iswcntrl_works=yes], [gl_cv_func_iswcntrl_works=no],
+            [AC_TRY_COMPILE([#include <stdlib.h>
+                          #if __GNU_LIBRARY__ == 1
+                          Linux libc5 i18n is broken.
+                          #endif], [],
+              [gl_cv_func_iswcntrl_works=yes], [gl_cv_func_iswcntrl_works=no])
+            ])
+        ])
+      if test $gl_cv_func_iswcntrl_works = yes; then
+        WCTYPE_H=
+      fi
     fi
     dnl Compute NEXT_WCTYPE_H even if WCTYPE_H is empty,
     dnl for the benefit of builds from non-distclean directories.
@@ -41,4 +64,11 @@ AC_DEFUN([gl_WCTYPE_H],
   fi
   AC_SUBST([HAVE_WCTYPE_H])
   AC_SUBST([WCTYPE_H])
+
+  if test "$gl_cv_func_iswcntrl_works" = no; then
+    REPLACE_ISWCNTRL=1
+  else
+    REPLACE_ISWCNTRL=0
+  fi
+  AC_SUBST([REPLACE_ISWCNTRL])
 ])