Open the LUAI_ASSERT macro, and then run this code, it will get an assertion failure.
I'm not seeing this on MacOS (neither x86_64 nor ARM v8), but I do see this on Debian Linux 10.8 (for x86_64)
The issue is on line 66 of ldebug.c. The bug is in the assertion, the value of 'i' in this test is -1, which makes the second test of the assertion use the index -1 for the array f->abslineinfo. I don't believe there's anything wrong with the code beyond the assertion.
I changed the assertion to:
lua_assert(i == -1 || (i >= 0 && i < f->sizeabslineinfo && f->abslineinfo[i].pc <= pc));.
and all seems to be fine now.
Gé
