On vxworks, after destroying the semaphore used to implement a mutex,
__gthread_mutex_lock fails and __gnu_cxx::__mutex::lock calls
__throw_concurrence_lock_error. Nothing ensures the mutex_pool
mutexes survive init-once objects containing _Safe_sequence_base. If
such an object completes construction before mutex_pool
initialization, it will be registered for atexit destruction after the
mutex_pool mutexes, so the _M_detach_all() call in the
_Safe_sequence_base dtor will use already-destructed mutexes, and
basic_string/requirements/citerators_cc fails calling terminate.
This patch fixes this problem by ensuring the mutex pool completes
construction before any _Safe_sequence_base-containing object, so that
the mutex pool survives them all.
Regstrapped on x86_64-linux-gnu.
Tested on arm-vxworks7 (gcc-12) and arm-eabi (trunk). Ok to install?
for libstdc++-v3/ChangeLog
* include/debug/safe_base.h (_Safe_sequence_base): Ensure
the mutex pool survives *this.
---
libstdc++-v3/include/debug/safe_base.h | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/libstdc++-v3/include/debug/safe_base.h
b/libstdc++-v3/include/debug/safe_base.h
index 1dfa9f68b65b5..d4ba404cdac6e 100644
--- a/libstdc++-v3/include/debug/safe_base.h
+++ b/libstdc++-v3/include/debug/safe_base.h
@@ -203,7 +203,15 @@ namespace __gnu_debug
// Initialize with a version number of 1 and no iterators
_Safe_sequence_base() _GLIBCXX_NOEXCEPT
: _M_iterators(0), _M_const_iterators(0), _M_version(1)
- { }
+ {
+ // Make sure the mutex_pool machinery is initialized before any
+ // full object containing a _Safe_sequence_base completes
+ // construction, so that any local static mutexes in the mutex
+ // pool won't be destructed before our destructor runs;
+ // _M_detach_all could fail otherwise, on targets whose mutexes
+ // stop working after being destroyed.
+ (void)this->_M_get_mutex();
+ }
#if __cplusplus >= 201103L
_Safe_sequence_base(const _Safe_sequence_base&) noexcept
--
Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/
Free Software Activist GNU Toolchain Engineer
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