On a recent mingw, the new wctob() test fails to compile:
../../gltests/test-wctob.c:24:18: error: initialization of 'int
(*)(rpl_wint_t)' {aka 'int (*)(unsigned int)'} from incompatible pointer type
'int (__attribute__((cdecl)) *)(wint_t)' {aka 'int (__attribute__((cdecl))
*)(short unsigned int)'} [-Wincompatible-pointer-types]
24 | SIGNATURE_CHECK (wctob, int, (wint_t));
| ^~~~~
This patch adds a workaround: It enables a wctob override.
2026-09-20 Bruno Haible <[email protected]>
wctob: Fix parameter type on mingw.
* m4/wctob.m4 (gl_FUNC_WCTOB): If the gnulib headers override wint_t,
set REPLACE_WCTOB.
* modules/wctob (Files): Add wint_t.m4.
* doc/posix-functions/wctob.texi: Mention the problem on newer mingw.
diff --git a/doc/posix-functions/wctob.texi b/doc/posix-functions/wctob.texi
index 284530bb3d..e524427c39 100644
--- a/doc/posix-functions/wctob.texi
+++ b/doc/posix-functions/wctob.texi
@@ -13,6 +13,9 @@
This function is missing on some platforms:
Minix 3.1.8, HP-UX 11.00, mingw.
@item
+This function takes only a 16-bit integer argument on some platforms:
+mingw 14.
+@item
This function clobbers caller-owned registers on some platforms:
Cygwin 1.7.5.
@item
diff --git -w a/m4/wctob.m4 b/m4/wctob.m4
index 127fd18dc5..811657af8b 100644
--- a/m4/wctob.m4
+++ b/m4/wctob.m4
@@ -1,5 +1,5 @@
# wctob.m4
-# serial 17
+# serial 18
dnl Copyright (C) 2008-2026 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -15,7 +15,12 @@ AC_DEFUN([gl_FUNC_WCTOB]
HAVE_WCTOB=0
else
HAVE_WCTOB=1
-
+ dnl When we override wint_t, we also need to override the wctob function,
+ dnl since it takes a wint_t as parameter.
+ AC_REQUIRE([gt_TYPE_WINT_T])
+ if test $GNULIBHEADERS_OVERRIDE_WINT_T = 1; then
+ REPLACE_WCTOB=1
+ else
dnl Solaris 9 has the wctob() function but it does not work.
dnl Cygwin 1.7.2 has the wctob() function but it clobbers caller-owned
dnl registers, see <https://cygwin.com/ml/cygwin/2010-05/msg00015.html>.
@@ -25,8 +30,8 @@ AC_DEFUN([gl_FUNC_WCTOB]
AC_CACHE_CHECK([whether wctob works],
[gl_cv_func_wctob_works],
[
- dnl Initial guess, used when cross-compiling or when no suitable locale
- dnl is present.
+ dnl Initial guess, used when cross-compiling or when no suitable
+ dnl locale is present.
changequote(,)dnl
case "$host_os" in
# Guess no on Solaris <= 9 and Cygwin.
@@ -91,15 +96,15 @@ AC_DEFUN([gl_FUNC_WCTOB]
*yes) ;;
*) REPLACE_WCTOB=1 ;;
esac
- dnl When we adjust mbrtowc in the C locale, we need to adjust wctob as
well,
- dnl for consistency.
+ dnl When we adjust mbrtowc in the C locale, we need to adjust wctob
+ dnl as well, for consistency.
AC_REQUIRE([gl_MBRTOWC_C_LOCALE])
case "$gl_cv_func_mbrtowc_C_locale_sans_EILSEQ" in
*yes) ;;
- *) REPLACE_WCTOB=1
- ;;
+ *) REPLACE_WCTOB=1 ;;
esac
fi
+ fi
])
# Prerequisites of lib/wctob.c.
diff --git a/modules/wctob b/modules/wctob
index cfd3b898d1..96d562986f 100644
--- a/modules/wctob
+++ b/modules/wctob
@@ -4,6 +4,7 @@ wctob() function: convert wide character to unibyte character.
Files:
lib/wctob.c
m4/wctob.m4
+m4/wint_t.m4
m4/mbrtowc.m4
m4/locale-en.m4
m4/locale-fr.m4
