Survive static destruction order failure in AWSLogging accessors#3874
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makxenov wants to merge 1 commit into
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Survive static destruction order failure in AWSLogging accessors#3874makxenov wants to merge 1 commit into
makxenov wants to merge 1 commit into
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The logger is held in two namespace-scope shared_ptr statics. AWS clients owned by other translation units can be destroyed after these statics (the order of static destruction across translation units is unspecified) and may still call GetLogSystem()/Push/PopLogger while unwinding at process exit. Once the shared_ptrs have been destroyed, those calls touch freed objects. Move the two shared_ptrs into a LoggingSet struct guarded by a trivially destructible bool flag, LoggingSetAlive, which stays readable until the very end of the process. ~LoggingSet clears the flag; afterwards the accessors behave as if no logger is installed instead of reading the destroyed members.
makxenov
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Description of changes:
The logger is held in two namespace-scope shared_ptr statics. AWS clients owned by other translation units can be destroyed after these statics (the order of static destruction across translation units is unspecified) and may still call GetLogSystem()/Push/PopLogger while unwinding at process exit. Once the shared_ptrs have been destroyed, those calls touch freed objects.
Move the two shared_ptrs into a LoggingSet struct guarded by a trivially destructible bool flag, LoggingSetAlive, which stays readable until the very end of the process. ~LoggingSet clears the flag; afterwards the accessors behave as if no logger is installed instead of reading the destroyed members.
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