Random crashes in mac and linux "haxe" tests

[tobil4sk]

Test MacOS (Arm64) (4.3.4) / haxe

/Users/runner/work/_temp/72bb127a-6426-4be2-86ed-fce9d29fd2ee.sh: line 1: 15185 Segmentation fault: 11  bin/TestMain
Error: Process completed with exit code 139.

Test MacOS (Arm64) (latest) / haxe

Memory exhausted.
/Users/runner/work/_temp/d85ca6f0-43ca-4142-8d9d-60a39b2041fe.sh: line 1:  5788 Trace/BPT trap: 5       bin/TestMain
 try HXCPP_GC_BIG_BLOCKS.
Error: Process completed with exit code 133.

[tobil4sk]

Also seen on Linux:

Test Linux (64bit) (4.3.4) / haxe

Memory exhausted.
 try HXCPP_GC_BIG_BLOCKS.
/home/runner/work/_temp/53f21ede-c89c-4655-996f-755fa9b20bf1.sh: line 1:  3647 Illegal instruction     (core dumped) bin/TestMain
Error: Process completed with exit code 132.

[Aidan63]

I can re-create this locally in WSL, it always occurs in the TestGCThreaded test. I'm assuming what's happening is that some objects aren't being collected causing it to run out of memory in this high allocation test? I'll try and bisect which commit this started occurring on.

[Aidan63]

I've gone all the way back to 05/06/2025 when the millisecond resolution timer was added and the illegal instruction error still occurs, so it seems like this has been around for a while but has only just started cropping up in the CI?

Disabling the generation GC also makes no difference, the error still occurs. Maybe we do need to enable big blocks, but I can't see why the memory would be exhausted with those tests.

[tobil4sk]

Is there anything specific that needs to be done to reproduce it? or just running it a couple times until it crashes?

[Aidan63]

Yeah, I've been checking out hxcpp commits and then close / relevant haxe commits and building them together (I'm compiling the hxcpp tests with debug as well).

I've then been running while ./bin/TestMain-debug; do :; done to run the tests until they return a non zero exit.

When attaching a debugger the error occurs when allocating one of the wrapper classes in the TestGCThreaded test, it's hitting the final path where all allocation attempts return null.