Renderer allocates 'zero sized' hunk chunks
wtfbbqhax opened this issue · comments
GeneratePermanentShader allocates zero sized chunks via Hunk_Alloc. This may be benign but it probably is not.
First it updates state
Hunk_SwapBanks();
The size of the allocated block will be different depending on HUNK_DEBUG
#ifdef HUNK_DEBUG
size += sizeof(hunkblock_t);
#endif
// round to cacheline
size = (size+31)&~31;
With HUNK_DEBUG enabled size += 0
-> size = 64
Without size=0
It may cause a problem in release, or it may cause a problem in Debug builds which is not clear. Pointers are often tested on truthiness alone, rather than knowing the size of the allocation.
I added a counter to this and found it happens quite a lot, from startup loading ui main menu
p count_zero_sized_allocs
(int) $0 = 558
Adding a early return null
and the menu is still loaded, no issue, but it actually resulted in more memory allocation in most cases. The only values that decreased are "low tempHighwater", "high permanent" and "total hunks in use".
high tempHighwater is more than 2x the original
Interesting behavior