Hi, On 2010-04-05 I reported: > A simplified test case is attached. It crashes when optimized with -O2 > and works fine without optimization: > ... > The same behaviour also occurs when the test case uses the gnulib replacement > of mbsrtowcs. Therefore I think it's not a bug in Cygwin's mbsrtowcs function.
It turned out to be a very nasty bug in Cygwin's wctob() function. Reported at <http://cygwin.com/ml/cygwin/2010-05/msg00015.html>. This adds a workaround, so that the gnulib tests for Cygwin now pass. 2010-05-02 Bruno Haible <br...@clisp.org> wctob: Work around nasty Cygwin 1.7.2 bug. * m4/wctob.m4 (gl_FUNC_WCTOB): Detect the Cygwin bug. * doc/posix-functions/wctob.texi: Mention the Cygwin bug. --- doc/posix-functions/wctob.texi.orig Sun May 2 13:14:53 2010 +++ doc/posix-functions/wctob.texi Sun May 2 12:45:50 2010 @@ -12,6 +12,9 @@ This function is missing on some platforms: HP-UX 11.00, IRIX 5.3, Solaris 2.6, mingw, Interix 3.5. @item +This function clobbers caller-owned registers on some platforms: +Cygwin 1.7.2. +...@item This function does not work on some platforms: Solaris 9. @item --- m4/wctob.m4.orig Sun May 2 13:14:53 2010 +++ m4/wctob.m4 Sun May 2 13:14:38 2010 @@ -1,4 +1,4 @@ -# wctob.m4 serial 4 +# wctob.m4 serial 5 dnl Copyright (C) 2008-2010 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -17,6 +17,8 @@ else dnl Solaris 9 has the wctob() function but it does not work. + dnl Cygwin 1.7.2 has the wctob() function but it clobbers caller-owned + dnl registers, see <http://cygwin.com/ml/cygwin/2010-05/msg00015.html>. AC_REQUIRE([AC_PROG_CC]) AC_REQUIRE([gt_LOCALE_FR]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles @@ -27,14 +29,35 @@ dnl is present. changequote(,)dnl case "$host_os" in - # Guess no on Solaris <= 9. - solaris2.[1-9] | solaris2.[1-9].*) + # Guess no on Solaris <= 9 and Cygwin. + solaris2.[1-9] | solaris2.[1-9].* | cygwin*) gl_cv_func_wctob_works="guessing no" ;; # Guess yes otherwise. *) gl_cv_func_wctob_works="guessing yes" ;; esac changequote([,])dnl - if test $LOCALE_FR != none; then + case "$host_os" in + cygwin*) + AC_TRY_RUN([ +#include <locale.h> +#include <wchar.h> + +register long global __asm__ ("%ebx"); + +int main () +{ + setlocale (LC_ALL, "en_US.UTF-8"); + + global = 0x12345678; + if (wctob (0x00FC) != -1) + return 1; + if (global != 0x12345678) + return 2; + return 0; +}], [:], [gl_cv_func_wctob_works=no], [:]) + ;; + esac + if test "$gl_cv_func_wctob_works" != no && test $LOCALE_FR != none; then AC_TRY_RUN([ #include <locale.h> #include <string.h>
