Re: mbrtowc, mbrlen: Work around a NetBSD bug in UTF-8 locales

> 	mbrtowc, mbrlen: Work around a NetBSD bug in UTF-8 locales.

After this patch, on NetBSD, a testdir of
  mbrtowc mbsrtowcs mbsnrtowcs mbsrtoc32s mbsnrtoc32s
produces these test failures:


FAIL: test-mbsnrtoc32s-3.sh
===========================

../../gltests/test-mbsnrtoc32s.c:234: assertion 'ret == 4' failed
[1]   Abort trap (core dumped) LC_ALL="${testlocale}" ${CHECKER} ./test-mbsnr...
FAIL test-mbsnrtoc32s-3.sh (exit status: 134)

FAIL: test-mbsnrtowcs-3.sh
==========================

../../gltests/test-mbsnrtowcs.c:231: assertion 'ret == 4' failed
[1]   Abort trap (core dumped) LC_ALL="${testlocale}" ${CHECKER} ./test-mbsnr...
FAIL test-mbsnrtowcs-3.sh (exit status: 134)

FAIL: test-mbsrtoc32s-3.sh
==========================

../../gltests/test-mbsrtoc32s.c:234: assertion 'ret == 4' failed
[1]   Abort trap (core dumped) LC_ALL="${testlocale}" ${CHECKER} ./test-mbsrt...
FAIL test-mbsrtoc32s-3.sh (exit status: 134)

FAIL: test-mbsrtowcs-3.sh
=========================

../../gltests/test-mbsrtowcs.c:231: assertion 'ret == 4' failed
[1]   Abort trap (core dumped) LC_ALL="${testlocale}" ${CHECKER} ./test-mbsrt...
FAIL test-mbsrtowcs-3.sh (exit status: 134)


The cause is that the mbstate_t handling in rpl_mbrtowc is not exactly
compatible with the one in mbsrtowcs (due to the 'void *header' pointer).
So, we need to override mbsrtowcs as well. Another reason to do so is,
of course, the handling of invalid byte sequences.


2026-06-02  Bruno Haible  <[email protected]>

	mbrtowc: Work around a NetBSD bug in UTF-8 locales, part 2.
	* m4/mbsrtowcs.m4 (gl_FUNC_MBSRTOWCS): Also set REPLACE_MBSRTOWCS
	to 1 if gl_MBRTOWC_INVALID_UTF8 reports "no".
	* m4/mbsnrtowcs.m4 (gl_FUNC_MBSNRTOWCS): Also set REPLACE_MBSNRTOWCS
	to 1 if gl_MBRTOWC_INVALID_UTF8 reports "no".

diff --git a/m4/mbsnrtowcs.m4 b/m4/mbsnrtowcs.m4
index 500964f8e4..089f58d6df 100644
--- a/m4/mbsnrtowcs.m4
+++ b/m4/mbsnrtowcs.m4
@@ -1,5 +1,5 @@
 # mbsnrtowcs.m4
-# serial 11
+# serial 12
 dnl Copyright (C) 2008, 2010-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -38,6 +38,13 @@ AC_DEFUN([gl_FUNC_MBSNRTOWCS]
           *) REPLACE_MBSNRTOWCS=1 ;;
         esac
       fi
+      if test $REPLACE_MBSNRTOWCS = 0; then
+        gl_MBRTOWC_INVALID_UTF8
+        case "$gl_cv_func_mbrtowc_invalid_UTF8" in
+          *yes) ;;
+          *) REPLACE_MBSNRTOWCS=1 ;;
+        esac
+      fi
     fi
   fi
 ])
diff --git a/m4/mbsrtowcs.m4 b/m4/mbsrtowcs.m4
index df48432b2b..233fdcbc3a 100644
--- a/m4/mbsrtowcs.m4
+++ b/m4/mbsrtowcs.m4
@@ -1,5 +1,5 @@
 # mbsrtowcs.m4
-# serial 19
+# serial 20
 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,
@@ -41,6 +41,13 @@ AC_DEFUN([gl_FUNC_MBSRTOWCS]
           *) REPLACE_MBSRTOWCS=1 ;;
         esac
       fi
+      if test $REPLACE_MBSRTOWCS = 0; then
+        gl_MBRTOWC_INVALID_UTF8
+        case "$gl_cv_func_mbrtowc_invalid_UTF8" in
+          *yes) ;;
+          *) REPLACE_MBSRTOWCS=1 ;;
+        esac
+      fi
     fi
   fi
 ])