Hello GCC hackers, and thank you very much for your precious work here. I've been observing somewhat random GCC segfaults in my C++ 20 codebase for a while. By "random" I mean that if I rerun the cmake build after a failure, 75% out of the time it will succeed, and it might fail again the next time I try running the build. I have every reason to believe that the issue is not with my code because: 1) At the second (or more rarely third) attempt at running the build, it succeeds. 2) Clang does not segfault on the same codebase, and indeed produces correct code.
The codebase is fairly large and heavily templatized, so I know that the the compiler allocates a seemingly inordinate amount of memory (using top, I've seen it reach a RES size of 1.6GB and a VIRT size of 4GB), so I initially attributed the segfaults to lack of enough memory on my computer (16GB, with chrome running...). Now I turned on swap (32GB), and I see that even when gcc is running, there is plenty of available memory, so this is not a plausible cause. The possibility of a hardware glitch in my system also does not hold much water, as neither clang nor any other piece of software seems to exhibit any instability. It'd be great if I could get some guidance on how to investigate this issue further. If it were of value to the developers, I'd be happy to file a bug report, but given the randomness of the issue, I doubt that they'd be able to reproduce the problem even with a preprocessed file. What then is my path forward? Here's some information that might be relevant: $ cat /etc/debian_version 11.1 $ gcc --version gcc (Debian 10.2.1-6) 10.2.1 20210110 Copyright (C) 2020 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Thanks for any help! -- Alex Baretta t: 650-383-0227
