Tracy-instrumented application crashes in Tracy's static intializers when started through RenderDoc

[simonvanbernem]

When I try to start my game, which is instrumented using tracy, in RenderDoc, the game instantly crashes due to a static variable of Tracy's moodycamel queue failing to initialize. The actual violation is a nullptr dereference inside a critical section of malloc.

This is a bug that seems to be the result of some weird interaction and the tool RenderDoc: I originally thought this was an issue with RenderDoc, and reported it, but the maintainer pointed out to me that this is actually a crash in my application (see the issue at RenderDoc's Github for details).

The stacktrace shows that the crash happens, when malloc tries to take a lock duing the initialization of a ProducerToken inside of Tracy:

RtlpWaitOnCriticalSection
RtlpEnterCriticalSectionContended
RtlEnterCriticalSection
__acrt_lock Line 55 at minkernel\crts\ucrt\src\appcrt\internal\locks.cpp(55)
heap_alloc_dbg_internal Line 309 at minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp(309)
heap_alloc_dbg Line 450 at minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp(450)
_malloc_dbg Line 496 at minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp(496)
tracy::moodycamel::ConcurrentQueueDefaultTraits::WORKAROUND_malloc Line 224 at B:\spaced\source\tracy\client\tracy_concurrentqueue.h(224)
tracy::moodycamel::ConcurrentQueueDefaultTraits::malloc Line 226 at B:\spaced\source\tracy\client\tracy_concurrentqueue.h(226)
tracy::moodycamel::ConcurrentQueuetracy::QueueItem,tracy::moodycamel::ConcurrentQueueDefaultTraits::create<tracy::moodycamel::ConcurrentQueuetracy::QueueItem,tracy::moodycamel::ConcurrentQueueDefaultTraits::ExplicitProducer,tracy::moodycamel::ConcurrentQueuetracy::QueueItem,tracy::moodycamel::ConcurrentQueueDefaultTraits *> Line 1428 at B:\spaced\source\tracy\client\tracy_concurrentqueue.h(1428)
tracy::moodycamel::ConcurrentQueuetracy::QueueItem,tracy::moodycamel::ConcurrentQueueDefaultTraits::recycle_or_create_producer Line 1366 at B:\spaced\source\tracy\client\tracy_concurrentqueue.h(1366)
tracy::moodycamel::ConcurrentQueuetracy::QueueItem,tracy::moodycamel::ConcurrentQueueDefaultTraits::recycle_or_create_producer Line 1346 at B:\spaced\source\tracy\client\tracy_concurrentqueue.h(1346)
tracy::moodycamel::ProducerToken::ProducerTokentracy::QueueItem,tracy::moodycamel::ConcurrentQueueDefaultTraits Line 1458 at B:\spaced\source\tracy\client\tracy_concurrentqueue.h(1458)
tracy::`dynamic initializer for 's_token_detail'' Line 975 at B:\spaced\source\tracy\client\TracyProfiler.cpp(975)
__dyn_tls_init Line 79 at d:\agent_work\5\s\src\vctools\crt\vcstartup\src\tls\tlsdyn.cpp(79)
LdrpCallInitRoutine
LdrpCallTlsInitializers
LdrpInitializeThread
_LdrpInitialize
LdrpInitialize
LdrInitializeThunk

The maintainer of RenderDocs guess on the bug is the following:

If I had to guess I'd say that your code enters a critical section in some static initialiser that runs on thread attach, but the critical section isn't initialised until after main() is entered. RenderDoc injects a thread to insert its hooks which will run before main(), so any global initialisers that are fragile like this can break.

Now. I don't really know if this a bug in your code, or moodycamels, or even MSVC C++ library, but since you have comments in TracyProfiler.cpp that mention binary sections and initialization just above the code in question (lines 974 and 975) I hope that you might know how to fix this.

I am on tracy version 0.7

If you need to repro the issue, I can send you my application+renderdoc and instructions on how to repro. It should take only a couple of minutes.

[wolfpld]

Sorry, I can't reproduce this. On my side RenderDoc is able to correctly launch a profiled application.

Have you tried compiling your program with TRACY_DELAYED_INIT define?

[simonvanbernem]

TRACY_DELAYED_INIT did the trick, thanks! I can send you my application for repro if you want to dig into this, although I understand if you don't want to.

[wolfpld]

Sure, I can take a look.

[simonvanbernem]

I sent you a mail with a link to my OneDrive.

[wolfpld]

Closing, as a workaround exists.