Using the reproduction steps Tim shared [1], this patch fixes the
redeclaration on MinGW:
depbase=`echo nanosleep.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
x86_64-w64-mingw32-gcc -DHAVE_CONFIG_H -I. -I.. -DGNULIB_STRICT_CHECKING=1
-g -O2 -MT nanosleep.o -MD -MP -MF $depbase.Tpo -c -o nanosleep.o nanosleep.c
&&\
mv -f $depbase.Tpo $depbase.Po
nanosleep.c:97:1: error: redefinition of 'nanosleep'
97 | nanosleep (const struct timespec *requested_delay,
| ^~~~~~~~~
In file included from /usr/share/mingw-w64/include/time.h:323,
from ./time.h:54,
from nanosleep.c:23:
/usr/share/mingw-w64/include/pthread_time.h:79:39: note: previous
definition of 'nanosleep' with type 'int(const struct timespec *, struct
timespec *)'
79 | WINPTHREAD_NANOSLEEP_DECL int __cdecl nanosleep(const struct
timespec *request, struct timespec *remain)
| ^~~~~~~~~
make[4]: *** [Makefile:2248: nanosleep.o] Error 1
I left the cross guess as "no" so the function gets replaced. This is
because MinGW does not use QueryPerformanceCounter, so I assume that
does not work as well for small durations [2].
I'm not sure if that is correct and/or if it should be documented. So I
will hold off pushing for review.
Collin
[1] https://savannah.gnu.org/bugs/?67704
[2]
https://github.com/mingw-w64/mingw-w64/blob/master/mingw-w64-libraries/winpthreads/src/nanosleep.c
>From 863693dd36aeab6803dbb46566f066f98339a0b5 Mon Sep 17 00:00:00 2001
Message-ID: <863693dd36aeab6803dbb46566f066f98339a0b5.1763263302.git.collin.fu...@gmail.com>
From: Collin Funk <[email protected]>
Date: Sat, 15 Nov 2025 19:11:53 -0800
Subject: [PATCH] nanosleep: Avoid a redefinition on MinGW.
Reported by Tim Ruehsen in
<https://savannah.gnu.org/bugs/?67704>.
* m4/nanosleep.m4 (gl_FUNC_NANOSLEEP): Check for nanosleep is found in
-lpthread.
---
ChangeLog | 8 ++++++++
m4/nanosleep.m4 | 5 +++--
2 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index bce004b202..ce925711b0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2025-11-15 Collin Funk <[email protected]>
+
+ nanosleep: Avoid a redefinition on MinGW.
+ Reported by Tim Ruehsen in
+ <https://savannah.gnu.org/bugs/?67704>.
+ * m4/nanosleep.m4 (gl_FUNC_NANOSLEEP): Check for nanosleep is found in
+ -lpthread.
+
2025-11-15 Paul Eggert <[email protected]>
-Wunused-const-variable started in GCC 6.1 not 4.4
diff --git a/m4/nanosleep.m4 b/m4/nanosleep.m4
index 81c45d8a31..a02ee233eb 100644
--- a/m4/nanosleep.m4
+++ b/m4/nanosleep.m4
@@ -1,5 +1,5 @@
# nanosleep.m4
-# serial 47
+# serial 48
dnl Copyright (C) 1999-2001, 2003-2025 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -24,9 +24,10 @@ AC_DEFUN([gl_FUNC_NANOSLEEP]
# Solaris 2.5.1 needs -lposix4 to get the nanosleep function.
# Solaris 7 prefers the library name -lrt to the obsolescent name -lposix4.
+ # MinGW uses needs -lpthread to get the nanosleep function.
NANOSLEEP_LIB=
AC_SUBST([NANOSLEEP_LIB])
- AC_SEARCH_LIBS([nanosleep], [rt posix4],
+ AC_SEARCH_LIBS([nanosleep], [rt posix4 pthread],
[test "$ac_cv_search_nanosleep" = "none required" ||
NANOSLEEP_LIB=$ac_cv_search_nanosleep])
if test "x$ac_cv_search_nanosleep" != xno; then
--
2.51.1
