Materialization ABI and linking

MCT participates in object and image generation. The backend translates program decisions into target-compatible bytes and metadata. Linking must resolve symbols and relocations without accidentally relying on retained artifacts from an earlier build.

V81 changes native sources including native_body.n, mct.n, mct_object.n, mct_link.n and mct_image_elf.n. Their responsibilities include stack intervals, temporaries, arguments, returns, symbol alignment and alignment against final virtual addresses.

ABI details remain significant when the source is unchanged. Aggregates may travel by reference on Win64 or through a realigned argument area on SysV. Validation includes direct and indirect calls, aggregate returns, nesting and recursion.

The linked runtime must match the symbols emitted by the compiler. Successful analysis does not resolve a missing export. Provider identity, dependencies and library search rules are part of the reproduction.

Caches contain derived materials. Cache identity must change when the emitter contract changes. V81 rejects corrupt materials even after their manifest digests are recomputed: a matching digest does not validate an altered artifact's internal structure.

Retain source, IR or material, object, image and process output separately when investigating regressions. Printed output alone can conceal differences in layout, linkage and sections that surface in another program.