jmap_dumper: validate the resolved GUObjectArray against the struct invariants (fixes #30, UE 5.8 empty dumps) - #31
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September 18, 2026 19:26
…nvariants and walk to the real base when a neighbouring member was matched (UE 5.8 shipping builds resolve to ObjAvailableListEstimateCount, +0x68 — trumank#30)
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On UE 5.8 shipping builds (Dark and Darker build 25384861, and the Spellsided report in #30) patternsleuth resolves
GUObjectArrayto a neighbouring member ofFUObjectArray—ObjAvailableListEstimateCountat +0x68 — because 5.8 movedObjObjectsto the front of the struct. The>= 508gospel layout is right, the base is wrong, so the dumper reads a zeroed struct and writes 0 objects.This PR validates the resolved address against the struct's own invariants (readable chunk table,
0 < NumElements <= MaxElements,NumChunks == ceil(NumElements / 65536) <= MaxChunks, readable first chunk) and, when it fails, walks ±0x200 in 8-byte steps to the first address that satisfies them, logging the adjustment. User-supplied--guobject-arrayoverrides are never touched.Verified against the frozen 5.8 game in a sandbox:
GUObjectArray pattern resolved to 0x14DFE3468 … using 0x14DFE3400 (-0x68)→ 48,599 objects / 7,693 vtables (previously 0 / 0). Offsets checked against Epic's 5.8UObjectArray.h.