libstdc++: Allow std::condition_variable waits to be cancelled [PR103382]
std::condition_variable::wait(unique_lock<mutex>&) is incorrectly marked noexcept, which means that the __forced_unwind exception used by NPTL cancellation will terminate the process. It should allow exceptions to pass through, so that a thread can be cleanly cancelled when waiting on a condition variable. The new behaviour is exported as a new version of the symbol, to avoid an ABI break for existing code linked to the non-throwing definition of the function. Code linked against older releases will have a reference to the @GLIBCXX_3.4.11 version, andcode compiled against the new libstdc++ will get a reference to the @@GLIBCXX_3.4.30 version. libstdc++-v3/ChangeLog: PR libstdc++/103382 * config/abi/pre/gnu.ver (GLIBCXX_3.4.11): Do not export old symbol if .symver renaming is supported. (GLIBCXX_3.4.30): Export new symbol if .symver renaming is supported. * doc/xml/manual/evolution.xml: Document change. * doc/html/manual/api.html: Regenerate. * include/bits/std_mutex.h (__condvar::wait, __condvar::wait_until): Remove noexcept. * include/std/condition_variable (condition_variable::wait): Likewise. * src/c++11/condition_variable.cc (condition_variable::wait): Likewise. * src/c++11/compatibility-condvar.cc (__nothrow_wait_cv::wait): Define nothrow wrapper around std::condition_variable::wait and export the old symbol as an alias to it. * testsuite/30_threads/condition_variable/members/103382.cc: New test.
This commit is contained in:
parent
db5fa0837e
commit
9e18a25331
|
@ -1285,7 +1285,6 @@ GLIBCXX_3.4.11 {
|
||||||
# condition_variable
|
# condition_variable
|
||||||
_ZNSt18condition_variable10notify_allEv;
|
_ZNSt18condition_variable10notify_allEv;
|
||||||
_ZNSt18condition_variable10notify_oneEv;
|
_ZNSt18condition_variable10notify_oneEv;
|
||||||
_ZNSt18condition_variable4waitERSt11unique_lockISt5mutexE;
|
|
||||||
_ZNSt18condition_variableC1Ev;
|
_ZNSt18condition_variableC1Ev;
|
||||||
_ZNSt18condition_variableC2Ev;
|
_ZNSt18condition_variableC2Ev;
|
||||||
_ZNSt18condition_variableD1Ev;
|
_ZNSt18condition_variableD1Ev;
|
||||||
|
@ -1295,6 +1294,12 @@ GLIBCXX_3.4.11 {
|
||||||
_ZNSt22condition_variable_anyD1Ev;
|
_ZNSt22condition_variable_anyD1Ev;
|
||||||
_ZNSt22condition_variable_anyD2Ev;
|
_ZNSt22condition_variable_anyD2Ev;
|
||||||
|
|
||||||
|
#ifndef HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT
|
||||||
|
# The original definition of this symbol gets versioned as @GLIBCXX_3.4.11
|
||||||
|
# if ".symver" is supported, or as @@GLIBCXX_3.4.11 otherwise.
|
||||||
|
_ZNSt18condition_variable4waitERSt11unique_lockISt5mutexE;
|
||||||
|
#endif
|
||||||
|
|
||||||
# thread
|
# thread
|
||||||
_ZNSt6thread4joinEv;
|
_ZNSt6thread4joinEv;
|
||||||
_ZNSt6thread6detachEv;
|
_ZNSt6thread6detachEv;
|
||||||
|
@ -2401,6 +2406,11 @@ GLIBCXX_3.4.30 {
|
||||||
|
|
||||||
_ZSt21__glibcxx_assert_fail*;
|
_ZSt21__glibcxx_assert_fail*;
|
||||||
|
|
||||||
|
#ifdef HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT
|
||||||
|
# The new definition of this symbol gets versioned as @@GLIBCXX_3.4.30
|
||||||
|
_ZNSt18condition_variable4waitERSt11unique_lockISt5mutexE;
|
||||||
|
#endif
|
||||||
|
|
||||||
} GLIBCXX_3.4.29;
|
} GLIBCXX_3.4.29;
|
||||||
|
|
||||||
# Symbols in the support library (libsupc++) have their own tag.
|
# Symbols in the support library (libsupc++) have their own tag.
|
||||||
|
|
|
@ -450,4 +450,9 @@ options for <code class="option">--enable-libstdcxx-allocator</code> were remove
|
||||||
For the <code class="literal">new</code> option, <code class="classname">std::allocator</code>
|
For the <code class="literal">new</code> option, <code class="classname">std::allocator</code>
|
||||||
no longer derives from <code class="classname">__gnu_cxx::new_allocator</code>;
|
no longer derives from <code class="classname">__gnu_cxx::new_allocator</code>;
|
||||||
they both derive from <code class="classname">std::__new_allocator</code> instead.
|
they both derive from <code class="classname">std::__new_allocator</code> instead.
|
||||||
|
</p><p>
|
||||||
|
<code class="function">std::condition_variable::wait</code> changed to be
|
||||||
|
<code class="code">noexcept(false)</code> to allow thread cancellation exceptions to
|
||||||
|
be thrown from <code class="function">pthread_cond_wait</code> without aborting
|
||||||
|
the process.
|
||||||
</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="abi.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="appendix_porting.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="backwards.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ABI Policy and Guidelines </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Backwards Compatibility</td></tr></table></div></body></html>
|
</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="abi.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="appendix_porting.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="backwards.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ABI Policy and Guidelines </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Backwards Compatibility</td></tr></table></div></body></html>
|
|
@ -1041,6 +1041,13 @@ no longer derives from <classname>__gnu_cxx::new_allocator</classname>;
|
||||||
they both derive from <classname>std::__new_allocator</classname> instead.
|
they both derive from <classname>std::__new_allocator</classname> instead.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
<function>std::condition_variable::wait</function> changed to be
|
||||||
|
<code>noexcept(false)</code> to allow thread cancellation exceptions to
|
||||||
|
be thrown from <function>pthread_cond_wait</function> without aborting
|
||||||
|
the process.
|
||||||
|
</para>
|
||||||
|
|
||||||
</section>
|
</section>
|
||||||
|
|
||||||
</section>
|
</section>
|
||||||
|
|
|
@ -149,7 +149,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
||||||
|
|
||||||
// Expects: Calling thread has locked __m.
|
// Expects: Calling thread has locked __m.
|
||||||
void
|
void
|
||||||
wait(mutex& __m) noexcept
|
wait(mutex& __m)
|
||||||
{
|
{
|
||||||
int __e __attribute__((__unused__))
|
int __e __attribute__((__unused__))
|
||||||
= __gthread_cond_wait(&_M_cond, __m.native_handle());
|
= __gthread_cond_wait(&_M_cond, __m.native_handle());
|
||||||
|
@ -157,14 +157,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
||||||
}
|
}
|
||||||
|
|
||||||
void
|
void
|
||||||
wait_until(mutex& __m, timespec& __abs_time) noexcept
|
wait_until(mutex& __m, timespec& __abs_time)
|
||||||
{
|
{
|
||||||
__gthread_cond_timedwait(&_M_cond, __m.native_handle(), &__abs_time);
|
__gthread_cond_timedwait(&_M_cond, __m.native_handle(), &__abs_time);
|
||||||
}
|
}
|
||||||
|
|
||||||
#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
|
#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
|
||||||
void
|
void
|
||||||
wait_until(mutex& __m, clockid_t __clock, timespec& __abs_time) noexcept
|
wait_until(mutex& __m, clockid_t __clock, timespec& __abs_time)
|
||||||
{
|
{
|
||||||
pthread_cond_clockwait(&_M_cond, __m.native_handle(), __clock,
|
pthread_cond_clockwait(&_M_cond, __m.native_handle(), __clock,
|
||||||
&__abs_time);
|
&__abs_time);
|
||||||
|
|
|
@ -92,7 +92,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
||||||
notify_all() noexcept;
|
notify_all() noexcept;
|
||||||
|
|
||||||
void
|
void
|
||||||
wait(unique_lock<mutex>& __lock) noexcept;
|
wait(unique_lock<mutex>& __lock);
|
||||||
|
|
||||||
template<typename _Predicate>
|
template<typename _Predicate>
|
||||||
void
|
void
|
||||||
|
|
|
@ -54,4 +54,35 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
||||||
_GLIBCXX_END_NAMESPACE_VERSION
|
_GLIBCXX_END_NAMESPACE_VERSION
|
||||||
} // namespace std
|
} // namespace std
|
||||||
|
|
||||||
|
#if ! _GLIBCXX_INLINE_VERSION
|
||||||
|
// XXX GLIBCXX_ABI Deprecated
|
||||||
|
// gcc-12.1
|
||||||
|
// std::condition_variable::wait changed to noexcept(false)
|
||||||
|
#if defined(_GLIBCXX_SYMVER_GNU) && defined(_GLIBCXX_SHARED) \
|
||||||
|
&& defined(_GLIBCXX_HAVE_AS_SYMVER_DIRECTIVE) \
|
||||||
|
&& defined(_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
|
||||||
|
namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
|
||||||
|
{
|
||||||
|
struct __nothrow_wait_cv : std::condition_variable
|
||||||
|
{
|
||||||
|
void wait(std::unique_lock<std::mutex>&) noexcept;
|
||||||
|
};
|
||||||
|
|
||||||
|
__attribute__((used))
|
||||||
|
void
|
||||||
|
__nothrow_wait_cv::wait(std::unique_lock<std::mutex>& lock) noexcept
|
||||||
|
{
|
||||||
|
this->condition_variable::wait(lock);
|
||||||
|
}
|
||||||
|
} // namespace __gnu_cxx
|
||||||
|
|
||||||
|
// Export a noexcept wrapper around std::condition_variable::wait
|
||||||
|
// with the original @GLIBCXX_3.4.11 symbol version.
|
||||||
|
asm(
|
||||||
|
".symver _ZN9__gnu_cxx17__nothrow_wait_cv4waitERSt11unique_lockISt5mutexE,"
|
||||||
|
"_ZNSt18condition_variable4waitERSt11unique_lockISt5mutexE@GLIBCXX_3.4.11"
|
||||||
|
);
|
||||||
|
#endif
|
||||||
|
#endif
|
||||||
|
|
||||||
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
|
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
|
||||||
|
|
|
@ -36,7 +36,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
||||||
condition_variable::~condition_variable() noexcept = default;
|
condition_variable::~condition_variable() noexcept = default;
|
||||||
|
|
||||||
void
|
void
|
||||||
condition_variable::wait(unique_lock<mutex>& __lock) noexcept
|
condition_variable::wait(unique_lock<mutex>& __lock)
|
||||||
{
|
{
|
||||||
_M_cond.wait(*__lock.mutex());
|
_M_cond.wait(*__lock.mutex());
|
||||||
}
|
}
|
||||||
|
|
|
@ -0,0 +1,66 @@
|
||||||
|
// { dg-options "-pthread" }
|
||||||
|
// { dg-do run { target { *-*-linux* *-*-gnu* } } }
|
||||||
|
// { dg-require-effective-target c++11 }
|
||||||
|
// { dg-require-effective-target pthread }
|
||||||
|
// { dg-require-gthreads "" }
|
||||||
|
|
||||||
|
#include <condition_variable>
|
||||||
|
#include <chrono>
|
||||||
|
#include <mutex>
|
||||||
|
#include <thread>
|
||||||
|
|
||||||
|
// PR libstdc++/103382
|
||||||
|
|
||||||
|
template<typename F>
|
||||||
|
void
|
||||||
|
test_cancel(F wait)
|
||||||
|
{
|
||||||
|
std::mutex m;
|
||||||
|
std::condition_variable cv;
|
||||||
|
bool waiting = false;
|
||||||
|
|
||||||
|
std::thread t([&] {
|
||||||
|
std::unique_lock<std::mutex> lock(m);
|
||||||
|
waiting = true;
|
||||||
|
wait(cv, lock); // __forced_unwind exception should not terminate process.
|
||||||
|
});
|
||||||
|
|
||||||
|
// Ensure the condition variable is waiting before we cancel.
|
||||||
|
// This shouldn't be necessary because pthread_mutex_lock is not
|
||||||
|
// a cancellation point, but no harm in making sure we test what
|
||||||
|
// we intend to test: that cancel during a wait doesn't abort.
|
||||||
|
while (true)
|
||||||
|
{
|
||||||
|
std::unique_lock<std::mutex> lock(m);
|
||||||
|
if (waiting)
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
pthread_cancel(t.native_handle());
|
||||||
|
t.join();
|
||||||
|
}
|
||||||
|
|
||||||
|
int main()
|
||||||
|
{
|
||||||
|
test_cancel(
|
||||||
|
[](std::condition_variable& cv, std::unique_lock<std::mutex>& l) {
|
||||||
|
cv.wait(l);
|
||||||
|
});
|
||||||
|
|
||||||
|
test_cancel(
|
||||||
|
[](std::condition_variable& cv, std::unique_lock<std::mutex>& l) {
|
||||||
|
cv.wait(l, []{ return false; });
|
||||||
|
});
|
||||||
|
|
||||||
|
using mins = std::chrono::minutes;
|
||||||
|
|
||||||
|
test_cancel(
|
||||||
|
[](std::condition_variable& cv, std::unique_lock<std::mutex>& l) {
|
||||||
|
cv.wait_for(l, mins(1));
|
||||||
|
});
|
||||||
|
|
||||||
|
test_cancel(
|
||||||
|
[](std::condition_variable& cv, std::unique_lock<std::mutex>& l) {
|
||||||
|
cv.wait_until(l, std::chrono::system_clock::now() + mins(1));
|
||||||
|
});
|
||||||
|
}
|
Loading…
Reference in New Issue