Cesarus85--mjolnir-vr/docs/object_matching_logs/libcmt_handler_obj.md

libs/libcmt/handler.obj exact-match ledger

This atomic lane starts from campaign commit b831acac. Before editing it checked the project configuration, parked ledger, all Git refs, worktrees, existing logs, and active object ownership. The unit was genuinely MISSING, unparked, absent from all source/history searches, and unowned by another lane.

Plain-English behavior

This object owns the C++ allocation-failure callback used by the CRT. _set_new_handler takes the heap lock, replaces the callback, releases the lock, and returns the old callback. _query_new_handler returns the currently registered callback. _callnewh invokes it with the failed allocation size and returns one when allocation should be tried again, or zero when no handler is installed or the handler declines a retry.

The four-byte _pnhHeap variable stores the callback. It starts as null in .bss and is deliberately shared by all three routines.

Primary provenance and January inventory

The member obj\i386\handler.obj was extracted directly from the campaign's XDK 3911 libcmt.lib. Its CodeView records identify ordinary Microsoft C++ source:

..\handler.cpp
d:\xbox-finalfre\private\sdktools\crt\crtw32\heap\handler.cpp

Before source reconstruction, every runtime function and the owned .bss symbol in that authentic archive member compared strict-equal to the January split target. Thus the archive is exact source-provenance evidence, not merely a related CRT version.

Symbol	Kind	Bytes	Relocs	Normalized SHA-256
?_set_new_handler@@YAP6AHI@ZP6AHI@Z@Z	code	36	4	1bd9620e21577b86098fe0522b9694109f77e8a70b373f5594178aef7a07adb3
?_query_new_handler@@YAP6AHI@ZXZ	code	6	1	76811197299fd7215ff45276752d25eaa8889353ee70ada1fd839c8a55d34ffc
__callnewh	code	27	1	27149b6cf20a5ba1c8cf7723061c1780ae4f9a6484dc284f7799740a6ab10e80
?_pnhHeap@@3P6AHI@ZA	.bss data	4	0	df3f619804a92fdb4057192dc43dd748ea778adc52bc498ce80524c014b81119

The setter's four relocations are _lock at +0x04, _pnhHeap at +0x0E and +0x15, and _unlock at +0x1A. The query and call helper each have one _pnhHeap relocation at +0x01. Addresses, types, destinations, and addends match independently. The unit owns no .data or .rdata.

Experiment record

ID	Readable source shape	Measured result
E01	Typed _PNH global, lock-protected setter, direct query, and a local callback followed by the ordinary null-or-false predicate	All three functions and the .bss owner matched on the first compile

No alternate spellings were tried because E01 already reproduced every target property. The callback local in _callnewh states the semantic requirement that one callback value is tested and then invoked; it is not a register hint.

Strict verification

The .c repository filename is compiled as C++ with the same explicit /TP object option already used by the adjacent new.obj and delete.obj. XDK 3911 CL 13.00.9254.1 uses the unchanged libcmt flags /O1 /Gy /TP and the normal XDK include path.

The hardened comparator reports section_infos_equal for all three functions and the four-byte .bss owner. Independent COFF inspection confirms three external pick-no-duplicates .text COMDATs, the external C++-decorated BSS owner, correct storage classes, and no extra runtime ownership. Compiler .drectve and CodeView sections are discardable metadata, not linked runtime data.

The final gate record below is filled only from commands run in this isolated lane; historical objects are not accepted as proof.

• A forced rebuild of handler.obj remained exact, and both halobetacache_build and libcmt_build completed successfully as part of a clean 560-target build/report run.
• Progress credits 356/833 objects overall and 89/212 libcmt objects. Libcmt reaches 136/476 exact functions, 9,212/55,015 exact code bytes, and 3,476/8,637 exact data bytes.
• The semantic audit scanned 457 units and 3,573 functions, accepted 3,489 exact functions, and reported zero unit errors.
• The admission audit reports no candidate or revocation. Its one contradicted source/shell/shell_xbox item is the known pre-existing shell issue and does not involve this unit.
• The clean-commit regression snapshot/check and complete tooling-test result are recorded after the object commit, as required by the fail-closed gate.

House/Berth and bug audit

The implementation uses the public _PNH type from <new.h>, named lock constant, explicit linkage at the C/C++ boundary, vertically formatted parameters, and explicit returns. It directly states the allocation-handler behavior in readable C++.

There is no assembly, volatile, forced inlining, undefined behavior, byte forcing, raw structure offset, compiler pragma, alignment trick, opaque codegen cast, comparator exception, or compiler-flag change. Multiple returns in _callnewh reflect the target's two distinct success/failure epilogues and make the behavior clearer than a forced accumulator. No original January bug was found, so no bug-preservation comment is required.