Compiling a testdir with Oracle Developer Studio 12.6 (SunPRO C) on Linux, I get this compilation error:
CC -m64 -O -DHAVE_CONFIG_H -DEXEEXT=\"\" -DEXEEXT=\"\" -I. -I../../gltests -I.. -DGNULIB_STRICT_CHECKING=1 -DIN_GNULIB_TESTS=1 -I. -I../../gltests -I.. -I../../gltests/.. -I../gllib -I../../gltests/../gllib -I/home/bruno/inst-x86_64-64-suncc/include -Wall -Wno-error -g -c -o test-pthread-c++.o ../../gltests/test-pthread-c++.cc "../gllib/pthread.h", line 2436: Error: Cannot return extern "C" int(volatile int*,int) from a function that should return int(*)(pthread_mutex_t*,int). "../gllib/pthread.h", line 2463: Error: Cannot return extern "C" int(volatile int*) from a function that should return int(*)(pthread_mutex_t*). "../gllib/pthread.h", line 2490: Error: Cannot return extern "C" int(volatile int*) from a function that should return int(*)(pthread_mutex_t*). "../gllib/pthread.h", line 2517: Error: Cannot return extern "C" int(volatile int*) from a function that should return int(*)(pthread_mutex_t*). "../gllib/pthread.h", line 2544: Error: Cannot return extern "C" int(volatile int*) from a function that should return int(*)(pthread_mutex_t*). 5 Error(s) detected. make[4]: *** [Makefile:25912: test-pthread-c++.o] Error 2 The cause is that the generated pthread.h overrides pthread_spinlock_t, although it shouldn't: On glibc, the pthread spinlock functions exist and work fine. This patch fixes it. 2024-03-28 Bruno Haible <br...@clisp.org> pthread-h: Fix override of pthread_spinlock_t with non-GNU compilers. * m4/pthread-spin.m4 (gl_PTHREAD_SPIN): Define through AC_DEFUN_ONCE. Require gl_PTHREAD_H_DEFAULTS, not gl_PTHREAD_H. * m4/pthread_h.m4 (gl_PTHREAD_H): Invoke gl_PTHREAD_SPIN. * lib/pthread.in.h (pthread_spinlock_t, GNULIB_defined_pthread_spin_types): Don't define if HAVE_PTHREAD_SPIN_INIT && !REPLACE_PTHREAD_SPIN_INIT. * modules/pthread-h (Files): Add m4/pthread-spin.m4. diff --git a/lib/pthread.in.h b/lib/pthread.in.h index cd705fbd18..81598616df 100644 --- a/lib/pthread.in.h +++ b/lib/pthread.in.h @@ -417,16 +417,21 @@ typedef pthread_mutex_t pthread_spinlock_t; #else # if @HAVE_PTHREAD_SPINLOCK_T@ /* <pthread.h> exists and defines pthread_spinlock_t. */ -# if !(((__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7) \ - || __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 1)) \ - || (((__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)) \ - && !defined __ANDROID__) \ - || __clang_major__ >= 3)) \ - && !defined __ibmxl__) +# if !@HAVE_PTHREAD_SPIN_INIT@ || @REPLACE_PTHREAD_SPIN_INIT@ +/* If the 'pthread-spin' module is in use, it defines all the pthread_spin* + functions. Prepare for it by overriding pthread_spinlock_t if that might + be needed. */ +# if !(((__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7) \ + || __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 1)) \ + || (((__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)) \ + && !defined __ANDROID__) \ + || __clang_major__ >= 3)) \ + && !defined __ibmxl__) /* We can't use GCC built-ins. Approximate spinlocks with mutexes. */ -# if !GNULIB_defined_pthread_spin_types -# define pthread_spinlock_t pthread_mutex_t -# define GNULIB_defined_pthread_spin_types 1 +# if !GNULIB_defined_pthread_spin_types +# define pthread_spinlock_t pthread_mutex_t +# define GNULIB_defined_pthread_spin_types 1 +# endif # endif # endif # else diff --git a/m4/pthread-spin.m4 b/m4/pthread-spin.m4 index 05c38ba3cc..deb463774d 100644 --- a/m4/pthread-spin.m4 +++ b/m4/pthread-spin.m4 @@ -1,12 +1,12 @@ -# pthread-spin.m4 serial 6 +# pthread-spin.m4 serial 7 dnl Copyright (C) 2019-2024 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. -AC_DEFUN([gl_PTHREAD_SPIN], +AC_DEFUN_ONCE([gl_PTHREAD_SPIN], [ - AC_REQUIRE([gl_PTHREAD_H]) + AC_REQUIRE([gl_PTHREAD_H_DEFAULTS]) AC_REQUIRE([AC_CANONICAL_HOST]) if { case "$host_os" in mingw* | windows*) true;; *) false;; esac; } \ diff --git a/m4/pthread_h.m4 b/m4/pthread_h.m4 index c33afa0ce2..9954c81c17 100644 --- a/m4/pthread_h.m4 +++ b/m4/pthread_h.m4 @@ -1,4 +1,4 @@ -# pthread_h.m4 serial 9 +# pthread_h.m4 serial 10 dnl Copyright (C) 2009-2024 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 +41,8 @@ AC_DEFUN_ONCE([gl_PTHREAD_H] if test $ac_cv_type_pthread_spinlock_t != yes; then HAVE_PTHREAD_SPINLOCK_T=0 fi + dnl Set HAVE_PTHREAD_SPIN_INIT, REPLACE_PTHREAD_SPIN_INIT. + gl_PTHREAD_SPIN dnl Constants may be defined as C preprocessor macros or as enum items. diff --git a/modules/pthread-h b/modules/pthread-h index 6daa6d02a7..241671404c 100644 --- a/modules/pthread-h +++ b/modules/pthread-h @@ -5,6 +5,7 @@ Files: lib/pthread.in.h m4/pthread_h.m4 m4/threadlib.m4 +m4/pthread-spin.m4 Depends-on: extensions