Wasm: Question: conservative gc and heap_segment_allocated #8205
Description
In https://raw.githubusercontent.com/dotnet/corert/master/src/Native/gc/gc.cpp at line 17681 there is (this is too big a file for github to view normally, hence no permalink)
(printfs mine obviously)
heap_segment* seg = find_segment (interior, FALSE);
if (seg
#ifdef FEATURE_CONSERVATIVE_GC
&& (GCConfig::GetConservativeGC() || interior <= heap_segment_allocated(seg))
#endif
)
{
// If interior falls within the first free object at the beginning of a generation,
// we don't have brick entry for it, and we may incorrectly treat it as on large object heap.
int align_const = get_alignment_constant (heap_segment_read_only_p (seg)
#ifdef FEATURE_CONSERVATIVE_GC
|| (GCConfig::GetConservativeGC() && !heap_segment_uoh_p (seg))
#endif
);
#ifdef FEATURE_CONSERVATIVE_GC
printf("conservative gc\n");
#endif
if (interior >= heap_segment_allocated(seg))
{
printf("interior %08x seg %d heap_segment_allocated(seg) %08x\n", interior, seg, heap_segment_allocated(seg));
}
assert (interior < heap_segment_allocated (seg));
The first if condition has GCConfig::GetConservativeGC() || interior <= heap_segment_allocated(seg) so its possible to get inside with interior > heap_segment_allocated(seg) when GetConservativeGC() is true . A few lines later, there is the assert on interior < heap_segment_allocated (seg) which would fail in this scenario . I'm hitting this assert, so if this assert looks correct for conservative GC then I've got something wrong somewhere else. Can someone confirm this assert is valid for conservative GC?
Thanks.