Files
el/docs/v1/experiments/cycles/09-policy-inside-the-compiler.md
T
bigmerge c6ba0677f0 log v1 experiments: nineteen cycles, organised by the method that produced them
cycles/    one file per Ishikawa -> scientific method -> Six Sigma loop, named
           for the DEFECT not the fix, carrying the commit record as written at
           the time
findings/  what the cycles produced, cross-cut: live bugs, architecture answers,
           and defects in my own measurement

The organising finding is that predictions which came back FALSE produced every
significant result. Eleven of sixty-one failed, and those eleven found: that the
arity table was not drifted but 40% incomplete; that the AST traversal is
irreducible and only rules and judgments move; that guards could refuse through
the seam after all; and that routing el_bin_lookup through the gate did NOT fix
the SIGSEGV, because the fallback strlen was the hazard -- a wrong fix I would
otherwise have shipped as verified.

One cycle was run without committing predictions first and had to be discarded
as rigged. It is kept, in full, as 18-async-half-expressible.md.
2026-08-17 10:52:17 -05:00

2.0 KiB

policy inside the compiler

One Ishikawa → scientific method → Six Sigma loop. The record below is the commit message as written at the time, before the outcome was known to anyone reading this file.

Record — c2d9596

EXPERIMENT: the capability tier becomes shipped policy plus a query

Capability differs from prohibits_outside in one way that matters: a utility
program cannot be trusted to declare its own restrictions, because it would
declare none. So the policy comes from OUTSIDE the program -- it ships with the
language as data, editable without a compiler release.

  tools/check/capabilities.rel   18 names that were string literals in codegen
  tools/check/capabilities.sh    the query that decides

PREDICTIONS AND RESULTS
  P1 codegen emits kind + call graph, drops the 4 name tests   TRUE  zero #errors
  P2 the 18 literals become a data file                        TRUE
  P3 the checker catches capability violations                 TRUE  exit=1
  P4 codegen drops ~76 lines                                   TRUE  4963 -> 4881
  P5 below the 4661 baseline                                   FALSE ~+230

TWO DEFECTS THE HARNESS FOUND THAT READING WOULD NOT HAVE

1. Calls inside main became invisible. cg_fn returns early for main -- C
   provides its own -- so hooking the recording there left every call in main
   unrecorded: a blind spot exactly where a program does its work. The old
   cap_check_call ran from cg_expr and did see main. Moved the recording to
   cg_expr.

2. Caller attribution was stale. __cg_current_fn kept whatever cg_fn set last,
   so a violation in main was reported against the previously emitted function.
   The test still PASSED, because the violation was detected -- only the name
   was wrong, and a diagnostic naming the wrong fn is worse than none. Fixed at
   all three main-emission sites; the first patch missed two because the live
   path is codegen_streaming.

98/98 native, 7/7 + 4/4 + 5/5 integration, fixpoint ok.

Record — 29f78f9

land capability-as-policy: eighteen literals become a data file