pxx --version prints no build identity

Why run time, not build time

A binary cannot contain its own hash. A source commit embedded at build time would make the binary's bytes depend on git state, so selfcheck.sh, which rebuilds a bundle's binaries from the tarball where there is no .git, would stop reproducing MANIFEST.sha256. So the compiler hashes /proc/self/exe (SHA-256, in compiler.pas) and looks for that hash in records that already name binaries by hash:

A line is printed only when a record names the hash. A VERSION file that happens to sit nearby does not count.

tools/release.sh's build_dist now writes RELEASE-ID (tag, codename, source commit, and pin only when the release binary is the pinned one). The bundle's RELEASE.md lists it.

Measured (2026-09-29, fixedpoint d67ea56f34a7)

• The build: value equals sha256sum's first 12 digits for the binary with 0 to 63 extra bytes appended, which covers every padding case of the last block (64 of 64).
• A bundle made by the real build_dist (x86_64 only), then extracted fresh: compiler/pxx-x86_64 --version and compiler/pascal26 --version both print release: v0.1.0-beta.2 "Blaise" and source: ab6ab895b9bc. There is no pin: line, correctly, since that binary is not the pin.
• Checkout: a pin.log line in the real format that names the binary gives pin: v452 and source:, whether the binary sits in stable_linux_amd64/default/ or in compiler/. The make build gives local: with the stamp's source hash. A copy with no record gives local: not a pin or a release binary.
• --version takes about 0.5 s on this 8.8 MB binary, because of the hash.
• A Makefile row checks the build: line of both flags against sha256sum. The v451 pinned binary fails it.
• docs: reporting-bugs.md, release-notes/index.md and cli.md now ask for --version. They keep the sha256sum line for the v0.1.0-beta.1 archive, whose binary predates this change.