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@@ -1,82 +0,0 @@
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-From ee4af2ed0b7322884ec4ff537564683c3749b813 Mon Sep 17 00:00:00 2001
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-From: Jonathan Wakely <jwakely@redhat.com>
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-Date: Thu, 22 Dec 2022 09:56:47 +0000
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-Subject: [PATCH] libstdc++: Avoid recursion in __nothrow_wait_cv::wait
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- [PR105730]
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-
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-The commit r12-5877-g9e18a25331fa25 removed the incorrect
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-noexcept-specifier from std::condition_variable::wait and gave the new
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-symbol version @@GLIBCXX_3.4.30. It also redefined the original symbol
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-std::condition_variable::wait(unique_lock<mutex>&)@GLIBCXX_3.4.11 as an
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-alias for a new symbol, __gnu_cxx::__nothrow_wait_cv::wait, which still
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-has the incorrect noexcept guarantee. That __nothrow_wait_cv::wait is
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-just a wrapper around the real condition_variable::wait which adds
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-noexcept and so terminates on a __forced_unwind exception.
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-
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-This doesn't work on uclibc, possibly due to a dynamic linker bug. When
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-__nothrow_wait_cv::wait calls the condition_variable::wait function it
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-binds to the alias symbol, which means it just calls itself recursively
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-until the stack overflows.
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-
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-This change avoids the possibility of a recursive call by changing the
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-__nothrow_wait_cv::wait function so that instead of calling
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-condition_variable::wait it re-implements it. This requires accessing
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-the private _M_cond member of condition_variable, so we need to use the
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-trick of instantiating a template with the member-pointer of the private
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-member.
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-
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-libstdc++-v3/ChangeLog:
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-
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- PR libstdc++/105730
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- * src/c++11/compatibility-condvar.cc (__nothrow_wait_cv::wait):
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- Access private data member of base class and call its wait
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- member.
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-
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-Signed-off-by: Gleb Mazovetskiy <glex.spb@gmail.com>
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----
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- .../src/c++11/compatibility-condvar.cc | 22 ++++++++++++++++++-
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- 1 file changed, 21 insertions(+), 1 deletion(-)
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-
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-diff --git a/libstdc++-v3/src/c++11/compatibility-condvar.cc b/libstdc++-v3/src/c++11/compatibility-condvar.cc
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-index e3a8b8403ca..3cef3bc0714 100644
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---- a/libstdc++-v3/src/c++11/compatibility-condvar.cc
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-+++ b/libstdc++-v3/src/c++11/compatibility-condvar.cc
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-@@ -67,6 +67,24 @@ _GLIBCXX_END_NAMESPACE_VERSION
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- && defined(_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
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- namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
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- {
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-+namespace
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-+{
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-+ // Pointer-to-member for private std::condition_variable::_M_cond member.
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-+ std::__condvar std::condition_variable::* __base_member;
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-+
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-+ template<std::__condvar std::condition_variable::*X>
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-+ struct cracker
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-+ { static std::__condvar std::condition_variable::* value; };
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-+
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-+ // Initializer for this static member also initializes __base_member.
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-+ template<std::__condvar std::condition_variable::*X>
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-+ std::__condvar std::condition_variable::*
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-+ cracker<X>::value = __base_member = X;
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-+
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-+ // Explicit instantiation is allowed to access the private member.
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-+ template class cracker<&std::condition_variable::_M_cond>;
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-+}
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-+
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- struct __nothrow_wait_cv : std::condition_variable
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- {
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- void wait(std::unique_lock<std::mutex>&) noexcept;
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-@@ -76,7 +94,9 @@ __attribute__((used))
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- void
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- __nothrow_wait_cv::wait(std::unique_lock<std::mutex>& lock) noexcept
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- {
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-- this->condition_variable::wait(lock);
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-+ // In theory this could be simply this->std::condition_variable::wait(lock)
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-+ // but with uclibc that binds to the @GLIBCXX_3.4.11 symbol, see PR 105730.
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-+ (this->*__base_member).wait(*lock.mutex());
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- }
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- } // namespace __gnu_cxx
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-
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---
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-2.31.1
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-
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Romain Naour