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

libs/libcmt/towupper.obj exact-match ledger

This atomic lane starts from campaign commit 6f29c473. The object was MISSING at config index 820, absent from config/parked.json, every Git ref, worktree, and existing object log. The January target contains one function and no owned runtime data.

Plain-English behavior

towupper preserves the wide end-of-file marker. In the ordinary C locale it converts ASCII a through z to uppercase by subtracting 32 and returns every other character unchanged. In the Xbox CRT's nominal non-C-locale path it performs a lowercase-character classification call for values below 256 but still returns the original character.

Provenance and target inventory

The XDK 3911 libcmt.lib archive has SHA-256 60aa4c87c97eeb6662b31d9d37cf3caba1afabaec72c47b090e7a0ce8b632f55. Its obj\i386\towupper.obj member has SHA-256 36b1d99ed21417a7bc8f417a2cb96abce22024d16220a96b5526f755d8f0815b, compiler identifier 0x001c2426, ordinary C CodeView/line records, and source path d:\xbox-finalfre\private\sdktools\crt\crtw32\convert\towupper.c. This is direct Microsoft XDK CRT C provenance, not vendor assembly.

The archive member is itself strict-exact to the January runtime function:

• _towupper: 0x47/0x47, two relocations, normalized SHA-256 00ac224ed8e7c868ef9200556ebed5929194870b6050fa7ba34a75a3cebc0216;
• DIR32 at +0x11 to ___lc_handle + 8, proving the LC_CTYPE slot;
• REL32 at +0x3c to _iswctype + 0;
• external, one-byte-aligned, pick-no-duplicates .text COMDAT;
• no aliases and no target-owned .rdata, .data, or .bss.

The admitted towlower.obj is the exact inverse-shape donor. Its proven 16-bit wint_t/wctype_t, locale-index, WEOF, and ternary-return topology were mirrored while changing only the case range, arithmetic direction, and classification mask that the January towupper bytes prove.

Experiment matrix

ID	Source shape	Size T/B	Relocs T/B	Base hash	First divergence	Object result	Decision
E01	January/XDK donor topology: early WEOF return, C-locale ternary ASCII fold, then sub-256 iswctype(character, 2)	0x47/0x47	2/2	00ac224ed8e7...	none	sole function and all ownership exact	accepted on first compile

Any later experiment must vary one evidence-backed source factor, record all strict measurements here, and be reverted unless it improves the complete object result.

Strict verification

XDK 3911 CL 13.00.9254.1 compiled the accepted source with libcmt's exact /O1 /Gy /I"xbox/include" flags. The hardened comparator reports section_infos_equal: 0x47/0x47, both relocation addresses/types/destinations/addends exact, and normalized SHA-256 00ac224ed8e7c868ef9200556ebed5929194870b6050fa7ba34a75a3cebc0216. Independent COFF inspection confirms external linkage, one-byte alignment, and pick-no-duplicates COMDAT selection. Candidate .drectve and CodeView sections are discardable compiler metadata rather than runtime ownership.

The full halobetacache_build and libcmt_build pass. Regenerated progress reports 328/833 objects overall, 267/468 Halo objects, and 61/212 libcmt objects. Libcmt has 82/476 exact functions and 4,170/55,015 exact code bytes. This object contributes one object, one function, and 71 bytes from its fixed baseline. Data is unchanged. The semantic audit scans 431 units, evaluates 3,519 functions, accepts 3,435 exact functions, and reports zero unit errors.

The clean-commit fail-closed per-unit regression snapshot/check was followed by deletion of the generated object and a forced rebuild. _towupper remained still_exact, with no failures, warnings, changed non-exact siblings, newly exact surprises, or ownership changes. The complete tooling suite passes 179/179 tests.

House/Berth and original-bug audit

The candidate is readable typed C with explicit narrow types, named parameters, ordinary conditions, and no hidden byte control. It uses no assembly, volatile, forced inlining, undefined behavior, type-punning, opaque code-generation cast, packing/alignment trick, flag change, byte patch, or comparator waiver. The multiple source returns are the same measured natural CRT topology already proven necessary for the inverse towlower object; the compiler still emits one coherent function and the source remains clear.

The ignored classification result is preserved exactly because both January and the authentic XDK member prove it. This lane does not label it a definite original bug: the call may intentionally preserve CRT side effects or validation even though it does not map the character. A corrected locale-aware implementation would require a proven mapping API and is outside this exact reconstruction.