Remove configure-time thread safety checking (thread_test.c).

This testing was useful when it was written, nigh twenty years ago,
but it seems fairly pointless for any platform built in the last
dozen or more years.  (Compare also the comments at 8a2121185.)
Also we now have reports that the test program itself fails under
ThreadSanitizer.  Rather than invest effort in fixing it, let's
just drop it, and assume that the few people who still care
already know they need to use --disable-thread-safety.

Back-patch into v14, for consistency with 8a2121185.

Discussion: https://postgr.es/m/CADhDkKzPSiNvA3Hyq+wSR_icuPmazG0cFe=YnC3U-CFcYLc8Xw@mail.gmail.com
This commit is contained in:
Tom Lane 2021-07-24 12:16:39 -04:00
parent 678f5448c2
commit 76fa3db336
3 changed files with 57 additions and 636 deletions

View File

@ -1,433 +0,0 @@
/*-------------------------------------------------------------------------
*
* thread_test.c
* libc threading test program
*
* Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* config/thread_test.c
*
* This program tests to see if your standard libc functions use
* pthread_setspecific()/pthread_getspecific() to be thread-safe.
* See src/port/thread.c for more details.
*
* This program first tests to see if each function returns a constant
* memory pointer within the same thread, then, assuming it does, tests
* to see if the pointers are different for different threads. If they
* are, the function is thread-safe.
*
*-------------------------------------------------------------------------
*/
/* We cannot use c.h, as port.h will not exist yet */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <sys/types.h>
#include <pwd.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <pthread.h>
/* CYGWIN requires this for MAXHOSTNAMELEN */
#ifdef __CYGWIN__
#include <sys/param.h>
#endif
#ifdef WIN32
#define MAXHOSTNAMELEN 63
#include <winsock2.h>
#endif
#define TEMP_FILENAME_1 "thread_test.1"
#define TEMP_FILENAME_2 "thread_test.2"
static void func_call_1(void);
static void func_call_2(void);
static pthread_mutex_t init_mutex = PTHREAD_MUTEX_INITIALIZER;
static volatile int thread1_done = 0;
static volatile int thread2_done = 0;
static volatile int errno1_set = 0;
static volatile int errno2_set = 0;
#ifndef HAVE_STRERROR_R
static char *strerror_p1;
static char *strerror_p2;
static int strerror_threadsafe = 0;
#endif
#if !defined(WIN32) && !defined(HAVE_GETPWUID_R)
static struct passwd *passwd_p1;
static struct passwd *passwd_p2;
static int getpwuid_threadsafe = 0;
#endif
#if !defined(HAVE_GETADDRINFO) && !defined(HAVE_GETHOSTBYNAME_R)
static struct hostent *hostent_p1;
static struct hostent *hostent_p2;
static char myhostname[MAXHOSTNAMELEN];
static int gethostbyname_threadsafe = 0;
#endif
static int platform_is_threadsafe = 1;
int
main(int argc, char *argv[])
{
pthread_t thread1,
thread2;
int rc;
#ifdef WIN32
WSADATA wsaData;
int err;
#endif
if (argc > 1)
{
fprintf(stderr, "Usage: %s\n", argv[0]);
return 1;
}
/* Send stdout to 'config.log' */
close(1);
dup(5);
#ifdef WIN32
err = WSAStartup(MAKEWORD(2, 2), &wsaData);
if (err != 0)
{
fprintf(stderr, "Cannot start the network subsystem - %d**\nexiting\n", err);
exit(1);
}
#endif
#if !defined(HAVE_GETADDRINFO) && !defined(HAVE_GETHOSTBYNAME_R)
if (gethostname(myhostname, MAXHOSTNAMELEN) != 0)
{
fprintf(stderr, "Cannot get local hostname **\nexiting\n");
exit(1);
}
#endif
/* Hold lock until we are ready for the child threads to exit. */
pthread_mutex_lock(&init_mutex);
rc = pthread_create(&thread1, NULL, (void *(*) (void *)) func_call_1, NULL);
if (rc != 0)
{
fprintf(stderr, "Failed to create thread 1: %s **\nexiting\n",
strerror(errno));
exit(1);
}
rc = pthread_create(&thread2, NULL, (void *(*) (void *)) func_call_2, NULL);
if (rc != 0)
{
/*
* strerror() might not be thread-safe, and we already spawned thread
* 1 that uses it, so avoid using it.
*/
fprintf(stderr, "Failed to create thread 2 **\nexiting\n");
exit(1);
}
while (thread1_done == 0 || thread2_done == 0)
sched_yield(); /* if this is a portability problem, remove it */
/* Test things while we have thread-local storage */
/* If we got here, we didn't exit() from a thread */
#ifdef WIN32
printf("Your GetLastError() is thread-safe.\n");
#else
printf("Your errno is thread-safe.\n");
#endif
#ifndef HAVE_STRERROR_R
if (strerror_p1 != strerror_p2)
strerror_threadsafe = 1;
#endif
#if !defined(WIN32) && !defined(HAVE_GETPWUID_R)
if (passwd_p1 != passwd_p2)
getpwuid_threadsafe = 1;
#endif
#if !defined(HAVE_GETADDRINFO) && !defined(HAVE_GETHOSTBYNAME_R)
if (hostent_p1 != hostent_p2)
gethostbyname_threadsafe = 1;
#endif
/* close down threads */
pthread_mutex_unlock(&init_mutex); /* let children exit */
pthread_join(thread1, NULL); /* clean up children */
pthread_join(thread2, NULL);
/* report results */
#ifdef HAVE_STRERROR_R
printf("Your system has strerror_r(); it does not need strerror().\n");
#else
printf("Your system uses strerror() which is ");
if (strerror_threadsafe)
printf("thread-safe.\n");
else
{
printf("not thread-safe. **\n");
platform_is_threadsafe = 0;
}
#endif
#ifdef WIN32
printf("getpwuid_r()/getpwuid() are not applicable to Win32 platforms.\n");
#elif defined(HAVE_GETPWUID_R)
printf("Your system has getpwuid_r(); it does not need getpwuid().\n");
#else
printf("Your system uses getpwuid() which is ");
if (getpwuid_threadsafe)
printf("thread-safe.\n");
else
{
printf("not thread-safe. **\n");
platform_is_threadsafe = 0;
}
#endif
#ifdef HAVE_GETADDRINFO
printf("Your system has getaddrinfo(); it does not need gethostbyname()\n"
" or gethostbyname_r().\n");
#elif defined(HAVE_GETHOSTBYNAME_R)
printf("Your system has gethostbyname_r(); it does not need gethostbyname().\n");
#else
printf("Your system uses gethostbyname which is ");
if (gethostbyname_threadsafe)
printf("thread-safe.\n");
else
{
printf("not thread-safe. **\n");
platform_is_threadsafe = 0;
}
#endif
if (platform_is_threadsafe)
{
printf("\nYour platform is thread-safe.\n");
return 0;
}
else
{
printf("\n** YOUR PLATFORM IS NOT THREAD-SAFE. **\n");
return 1;
}
}
/*
* func_call_1
*/
static void
func_call_1(void)
{
#if !defined(HAVE_GETPWUID_R) || \
(!defined(HAVE_GETADDRINFO) && \
!defined(HAVE_GETHOSTBYNAME_R))
void *p;
#endif
#ifdef WIN32
HANDLE h1;
#else
int fd;
#endif
unlink(TEMP_FILENAME_1);
/* Set errno = EEXIST */
/* create, then try to fail on exclusive create open */
/*
* It would be great to check errno here but if errno is not thread-safe
* we might get a value from the other thread and mis-report the cause of
* the failure.
*/
#ifdef WIN32
if ((h1 = CreateFile(TEMP_FILENAME_1, GENERIC_WRITE, 0, NULL, OPEN_ALWAYS, 0, NULL)) ==
INVALID_HANDLE_VALUE)
#else
if ((fd = open(TEMP_FILENAME_1, O_RDWR | O_CREAT, 0600)) < 0)
#endif
{
fprintf(stderr, "Could not create file %s in current directory\n",
TEMP_FILENAME_1);
exit(1);
}
#ifdef WIN32
if (CreateFile(TEMP_FILENAME_1, GENERIC_WRITE, 0, NULL, CREATE_NEW, 0, NULL)
!= INVALID_HANDLE_VALUE)
#else
if (open(TEMP_FILENAME_1, O_RDWR | O_CREAT | O_EXCL, 0600) >= 0)
#endif
{
fprintf(stderr,
"Could not generate failure for exclusive file create of %s in current directory **\nexiting\n",
TEMP_FILENAME_1);
exit(1);
}
/*
* Wait for other thread to set errno. We can't use thread-specific
* locking here because it might affect errno.
*/
errno1_set = 1;
while (errno2_set == 0)
sched_yield();
#ifdef WIN32
if (GetLastError() != ERROR_FILE_EXISTS)
#else
if (errno != EEXIST)
#endif
{
#ifdef WIN32
fprintf(stderr, "GetLastError() not thread-safe **\nexiting\n");
#else
fprintf(stderr, "errno not thread-safe **\nexiting\n");
#endif
unlink(TEMP_FILENAME_1);
exit(1);
}
#ifdef WIN32
CloseHandle(h1);
#else
close(fd);
#endif
unlink(TEMP_FILENAME_1);
#ifndef HAVE_STRERROR_R
/*
* If strerror() uses sys_errlist, the pointer might change for different
* errno values, so we don't check to see if it varies within the thread.
*/
strerror_p1 = strerror(EACCES);
#endif
#if !defined(WIN32) && !defined(HAVE_GETPWUID_R)
passwd_p1 = getpwuid(0);
p = getpwuid(1);
if (passwd_p1 != p)
{
printf("Your getpwuid() changes the static memory area between calls\n");
passwd_p1 = NULL; /* force thread-safe failure report */
}
#endif
#if !defined(HAVE_GETADDRINFO) && !defined(HAVE_GETHOSTBYNAME_R)
/* threads do this in opposite order */
hostent_p1 = gethostbyname(myhostname);
p = gethostbyname("localhost");
if (hostent_p1 != p)
{
printf("Your gethostbyname() changes the static memory area between calls\n");
hostent_p1 = NULL; /* force thread-safe failure report */
}
#endif
thread1_done = 1;
pthread_mutex_lock(&init_mutex); /* wait for parent to test */
pthread_mutex_unlock(&init_mutex);
}
/*
* func_call_2
*/
static void
func_call_2(void)
{
#if !defined(HAVE_GETPWUID_R) || \
(!defined(HAVE_GETADDRINFO) && \
!defined(HAVE_GETHOSTBYNAME_R))
void *p;
#endif
unlink(TEMP_FILENAME_2);
/* Set errno = ENOENT */
/* This will fail, but we can't check errno yet */
if (unlink(TEMP_FILENAME_2) != -1)
{
fprintf(stderr,
"Could not generate failure for unlink of %s in current directory **\nexiting\n",
TEMP_FILENAME_2);
exit(1);
}
/*
* Wait for other thread to set errno. We can't use thread-specific
* locking here because it might affect errno.
*/
errno2_set = 1;
while (errno1_set == 0)
sched_yield();
#ifdef WIN32
if (GetLastError() != ENOENT)
#else
if (errno != ENOENT)
#endif
{
#ifdef WIN32
fprintf(stderr, "GetLastError() not thread-safe **\nexiting\n");
#else
fprintf(stderr, "errno not thread-safe **\nexiting\n");
#endif
exit(1);
}
#ifndef HAVE_STRERROR_R
/*
* If strerror() uses sys_errlist, the pointer might change for different
* errno values, so we don't check to see if it varies within the thread.
*/
strerror_p2 = strerror(EINVAL);
#endif
#if !defined(WIN32) && !defined(HAVE_GETPWUID_R)
passwd_p2 = getpwuid(2);
p = getpwuid(3);
if (passwd_p2 != p)
{
printf("Your getpwuid() changes the static memory area between calls\n");
passwd_p2 = NULL; /* force thread-safe failure report */
}
#endif
#if !defined(HAVE_GETADDRINFO) && !defined(HAVE_GETHOSTBYNAME_R)
/* threads do this in opposite order */
hostent_p2 = gethostbyname("localhost");
p = gethostbyname(myhostname);
if (hostent_p2 != p)
{
printf("Your gethostbyname() changes the static memory area between calls\n");
hostent_p2 = NULL; /* force thread-safe failure report */
}
#endif
thread2_done = 1;
pthread_mutex_lock(&init_mutex); /* wait for parent to test */
pthread_mutex_unlock(&init_mutex);
}

222
configure vendored
View File

@ -11939,121 +11939,6 @@ if test "$ac_res" != no; then :
fi
# Required for thread_test.c on Solaris
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing sched_yield" >&5
$as_echo_n "checking for library containing sched_yield... " >&6; }
if ${ac_cv_search_sched_yield+:} false; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
/* Override any GCC internal prototype to avoid an error.
Use char because int might match the return type of a GCC
builtin and then its argument prototype would still apply. */
#ifdef __cplusplus
extern "C"
#endif
char sched_yield ();
int
main ()
{
return sched_yield ();
;
return 0;
}
_ACEOF
for ac_lib in '' rt; do
if test -z "$ac_lib"; then
ac_res="none required"
else
ac_res=-l$ac_lib
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
ac_cv_search_sched_yield=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
if ${ac_cv_search_sched_yield+:} false; then :
break
fi
done
if ${ac_cv_search_sched_yield+:} false; then :
else
ac_cv_search_sched_yield=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_sched_yield" >&5
$as_echo "$ac_cv_search_sched_yield" >&6; }
ac_res=$ac_cv_search_sched_yield
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
fi
# Required for thread_test.c on Solaris 2.5:
# Other ports use it too (HP-UX) so test unconditionally
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing gethostbyname_r" >&5
$as_echo_n "checking for library containing gethostbyname_r... " >&6; }
if ${ac_cv_search_gethostbyname_r+:} false; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
/* Override any GCC internal prototype to avoid an error.
Use char because int might match the return type of a GCC
builtin and then its argument prototype would still apply. */
#ifdef __cplusplus
extern "C"
#endif
char gethostbyname_r ();
int
main ()
{
return gethostbyname_r ();
;
return 0;
}
_ACEOF
for ac_lib in '' nsl; do
if test -z "$ac_lib"; then
ac_res="none required"
else
ac_res=-l$ac_lib
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
ac_cv_search_gethostbyname_r=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
if ${ac_cv_search_gethostbyname_r+:} false; then :
break
fi
done
if ${ac_cv_search_gethostbyname_r+:} false; then :
else
ac_cv_search_gethostbyname_r=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_gethostbyname_r" >&5
$as_echo "$ac_cv_search_gethostbyname_r" >&6; }
ac_res=$ac_cv_search_gethostbyname_r
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
fi
# Cygwin:
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing shmget" >&5
$as_echo_n "checking for library containing shmget... " >&6; }
@ -12170,6 +12055,62 @@ fi
if test "$enable_thread_safety" = yes; then
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing gethostbyname_r" >&5
$as_echo_n "checking for library containing gethostbyname_r... " >&6; }
if ${ac_cv_search_gethostbyname_r+:} false; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
/* Override any GCC internal prototype to avoid an error.
Use char because int might match the return type of a GCC
builtin and then its argument prototype would still apply. */
#ifdef __cplusplus
extern "C"
#endif
char gethostbyname_r ();
int
main ()
{
return gethostbyname_r ();
;
return 0;
}
_ACEOF
for ac_lib in '' nsl; do
if test -z "$ac_lib"; then
ac_res="none required"
else
ac_res=-l$ac_lib
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
ac_cv_search_gethostbyname_r=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
if ${ac_cv_search_gethostbyname_r+:} false; then :
break
fi
done
if ${ac_cv_search_gethostbyname_r+:} false; then :
else
ac_cv_search_gethostbyname_r=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_gethostbyname_r" >&5
$as_echo "$ac_cv_search_gethostbyname_r" >&6; }
ac_res=$ac_cv_search_gethostbyname_r
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing pthread_barrier_wait" >&5
$as_echo_n "checking for library containing pthread_barrier_wait... " >&6; }
if ${ac_cv_search_pthread_barrier_wait+:} false; then :
@ -19456,57 +19397,6 @@ fi
fi
fi
# Thread testing
# We have to run the thread test near the end so we have all our symbols
# defined. Cross compiling throws a warning.
#
if test "$enable_thread_safety" = yes; then
if test "$PORTNAME" != "win32"
then
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking thread safety of required library functions" >&5
$as_echo_n "checking thread safety of required library functions... " >&6; }
_CFLAGS="$CFLAGS"
_LIBS="$LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
LIBS="$LIBS $PTHREAD_LIBS"
if test "$cross_compiling" = yes; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: maybe" >&5
$as_echo "maybe" >&6; }
{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING:
*** Skipping thread test program because of cross-compile build.
" >&5
$as_echo "$as_me: WARNING:
*** Skipping thread test program because of cross-compile build.
" >&2;}
else
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
#include "$srcdir/config/thread_test.c"
_ACEOF
if ac_fn_c_try_run "$LINENO"; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
$as_echo "yes" >&6; }
else
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
$as_echo "no" >&6; }
as_fn_error $? "thread test program failed
This platform is not thread-safe. Check the file 'config.log' for the
exact reason, or use --disable-thread-safety to disable thread safety." "$LINENO" 5
fi
rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
conftest.$ac_objext conftest.beam conftest.$ac_ext
fi
CFLAGS="$_CFLAGS"
LIBS="$_LIBS"
else
{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: *** skipping thread test on Win32" >&5
$as_echo "$as_me: WARNING: *** skipping thread test on Win32" >&2;}
fi
fi
# If compiler will take -Wl,--as-needed (or various platform-specific
# spellings thereof) then add that to LDFLAGS. This is much easier than
# trying to filter LIBS to the minimum for each executable.

View File

@ -1178,17 +1178,13 @@ AC_SEARCH_LIBS(shm_unlink, rt)
AC_SEARCH_LIBS(clock_gettime, [rt posix4])
# Solaris:
AC_SEARCH_LIBS(fdatasync, [rt posix4])
# Required for thread_test.c on Solaris
AC_SEARCH_LIBS(sched_yield, rt)
# Required for thread_test.c on Solaris 2.5:
# Other ports use it too (HP-UX) so test unconditionally
AC_SEARCH_LIBS(gethostbyname_r, nsl)
# Cygwin:
AC_SEARCH_LIBS(shmget, cygipc)
# *BSD:
AC_SEARCH_LIBS(backtrace_symbols, execinfo)
if test "$enable_thread_safety" = yes; then
AC_SEARCH_LIBS(gethostbyname_r, nsl)
AC_SEARCH_LIBS(pthread_barrier_wait, pthread)
fi
@ -2362,38 +2358,6 @@ if test "$enable_tap_tests" = yes; then
fi
fi
# Thread testing
# We have to run the thread test near the end so we have all our symbols
# defined. Cross compiling throws a warning.
#
if test "$enable_thread_safety" = yes; then
if test "$PORTNAME" != "win32"
then
AC_MSG_CHECKING([thread safety of required library functions])
_CFLAGS="$CFLAGS"
_LIBS="$LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
LIBS="$LIBS $PTHREAD_LIBS"
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[#include "$srcdir/config/thread_test.c"]])],
[AC_MSG_RESULT(yes)],
[AC_MSG_RESULT(no)
AC_MSG_ERROR([thread test program failed
This platform is not thread-safe. Check the file 'config.log' for the
exact reason, or use --disable-thread-safety to disable thread safety.])],
[AC_MSG_RESULT(maybe)
AC_MSG_WARN([
*** Skipping thread test program because of cross-compile build.
])])
CFLAGS="$_CFLAGS"
LIBS="$_LIBS"
else
AC_MSG_WARN([*** skipping thread test on Win32])
fi
fi
# If compiler will take -Wl,--as-needed (or various platform-specific
# spellings thereof) then add that to LDFLAGS. This is much easier than
# trying to filter LIBS to the minimum for each executable.