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.
I said prohibition could not move because "a #error has no runtime". That
conflated two separable things: WHEN a violation is detected (build time --
correct, and unchanged) and WHERE the rule and the checker live (the compiler
-- assumed).
A prohibition is a containment relation over the call graph. So codegen now
records what it saw:
sneaky calls raw_sql
allowed calls raw_sql
allowed calls @repository
repository calls prohibits:raw_sql
and tools/check/prohibitions.sh decides, at build time, outside the compiler.
PREDICTIONS AND RESULTS
P1 codegen can emit the call graph it already walks TRUE
P2 the check becomes a query outside the compiler TRUE
P3 all prohibition decisions leave codegen TRUE zero #errors now
P4 violations still caught at build time TRUE exit=1
P5 codegen drops below the 4661 baseline FALSE 4962, +301
P5 is the finding. The TRAVERSAL is irreducible -- you must walk the AST to
find calls, and those ~120 lines do not move no matter who decides. What is not
irreducible is the rule (which names) or the decision (#error). Those left. I
predicted the whole 223 lines would go because I had not separated walking from
adjudicating.
Still compiled, and measured rather than assumed: the capability-tier system
(cap_check_call, is_self_formation_call, is_dharma_call, is_llm_call,
cap_record_violation, emit_cap_violations) is 76 lines of the same shape --
prohibits_WITHIN rather than prohibits_outside, so the checker needs the
opposite polarity to absorb it.
98/98 native, 4/4 prohibition_query.sh, 7/7 seam_binding.sh, fixpoint ok.