fruix/docs/PROGRESS.md

Progress

2026-04-01 — Phase 1.1 started: Guile verified on FreeBSD amd64

Completed work:

• installed/confirmed guile3-3.0.10
• added a reusable verification harness:
  • tests/guile/run-phase1-verification.sh
  • tests/guile/verify-phase1.scm
  • tests/guile/modules/phase1/sample.scm
• verified the following on FreeBSD 15.0-STABLE amd64:
  • module loading
  • deterministic output generation
  • file I/O
  • process handling with primitive-fork/waitpid
  • loopback TCP sockets
  • FFI calls into libc
  • execution of Guix bootstrap-related code from (guix build make-bootstrap)
• wrote the results to docs/reports/phase1-guile-freebsd.md

Notable findings:

• guile3 and guile-3.0 are present, but there is no unversioned guile binary
• system* and open-pipe* currently segfault on this host (exit 139)
• despite that crash, the lower-level process primitives needed for further investigation do work

Current assessment:

• Phase 1.1 has a solid amd64 smoke-verification baseline
• Phase 1.1 is not fully complete yet because i386 has not been checked and the subprocess crash needs investigation
• verification harness committed as e380e88 (Add FreeBSD Guile verification harness)

2026-04-01 — Phase 1.1 follow-up: subprocess crash isolated

Completed work:

• added a dedicated subprocess diagnostic harness:
  • tests/guile/run-subprocess-diagnostics.sh
  • tests/guile/posix-spawn-freebsd-diagnostics.c
• reproduced crashes for:
  • system*
  • spawn
  • open-pipe*
• confirmed all three fail with SIGSEGV / exit 139
• confirmed native FreeBSD posix_spawn + posix_spawn_file_actions_addclosefrom_np works in a standalone C program
• confirmed FreeBSD behavior that triggers gnulib replacement logic:
  • posix_spawn_file_actions_adddup2 accepts an invalid fd in the gnulib probe
  • posix_spawn_file_actions_addopen accepts an invalid fd in the gnulib probe
  • posix_spawnp accepts a shebang-less executable script in the gnulib security probe
• wrote the analysis to docs/reports/phase1-guile-subprocess-crash.md

Conclusion:

• this is most likely an upstream Guile/gnulib ABI bug on FreeBSD, not a Guix-specific problem
• likely sequence:
  1. gnulib enables REPLACE_POSIX_SPAWN=1
  2. Guile still enables HAVE_POSIX_SPAWN_FILE_ACTIONS_ADDCLOSEFROM_NP
  3. Guile passes a gnulib replacement posix_spawn_file_actions_t object to native posix_spawn_file_actions_addclosefrom_np
  4. libc interprets gnulib struct fields as a native pointer and crashes
• evidence from the lldb core matches this hypothesis (*fa = 0x0000000600000008, consistent with gnulib _allocated=8, _used=6)

Current assessment:

• Phase 1.1 amd64 investigation is now much stronger and has a concrete root-cause hypothesis
• the next practical step is to validate a workaround or patch in Guile so subprocess helpers stop crashing
• after that, continue with Phase 1.2 (minimal native build environment / GNU Hello)

Recent commits:

• e380e88 — Add FreeBSD Guile verification harness
• cd721b1 — Update progress after Guile verification

Next recommended step:

1. patch or locally validate a fix for the addclosefrom_np / REPLACE_POSIX_SPAWN mismatch
2. re-run both Guile test harnesses after the fix
3. once subprocess behavior is stable, continue with Phase 1.2 (minimal native build environment / GNU Hello)