fix(verilog): declare the enums a spec imports (Closes #2316)

[gHashTag]

Closes #2316

What was wrong

gen_verilog_expr lowers Enum.variant to the flat identifier Enum_variant
whichever spec declared the enum. gen_verilog declared the matching
localparam only for enums a spec declares itself, so an enum arriving
through use produced a reference with nothing declaring it:

gen/mac.v:100: error: Unable to bind wire/reg/memory `Trit_neg' in `ZeroDSP_MAC.extract_trit.extract_trit_body'

specs/fpga/mac.t27 does use base::ops;, and base/ops.t27 declares
Trit = enum(i8) { neg = -1, zero = 0, pos = 1 }.

Enums only, not use_resolve::resolve

resolve() splices whole declarations -- functions, structs, constants -- and
the Verilog backend cannot lower most of them, while 492 of the 650 specs carry
a use line. An enum is the one case where the backend already does everything
except emit the declaration, so use_resolve::imported_enums returns
(enum, [(variant, value)]) and nothing else, and the backend emits it through
the same gen_verilog_enum a same-spec enum goes through.

Two filters keep the blast radius where it belongs:

• Referenced only -- an enum the module never names emits nothing.
  specs/fpga/uart.t27 imports both modules that declare Trit and never
  mentions it; its output is byte-identical to before. There is a test for
  exactly this.
• Never shadow -- a name the module already declares is dropped. A
  redeclaration is a compile error, so this pass may only ever ADD a declaration
  that nothing else provides.

Measured

The prebuilt t27c at fb88da234 regenerates mac.v byte-identical to the
fpga-verilog artifact of run 32358697899, so it is a faithful stand-in for the
emitter. With the three localparam lines at the exact position the enum
section occupies and nothing else changed:

	iverilog -g2012 -DSIMULATION gen/mac.v
as generated	28 errors
after	22 errors, 0 mentioning Trit_

Across all 650 specs, the ones that carry a use, reference Enum.variant, and
do not declare that enum locally are exactly six, and all six want Trit:
fpga/mac.t27, nn/attention.t27, nn/hslm.t27, vsa/ops.t27, and the two
demos/jones_topology_* -- the last two import only base::types, which is
NOPARSE, so they are unchanged by this.

What this does NOT do

fpga-conformance stays red at 4/32. mac.v still fails on 22 errors, and
26 of the 28 failing modules fail on a defect this PR does not touch: a
struct-typed function parameter is declared as one scalar and then referenced
through <param>_<field> names nothing declares -- word_raw,
mac_units_status, cfg_addr_width, 202 distinct identifiers. The emitter is
internally inconsistent there (packed bit-slices in some places, per-field regs
in others, <param>_<field> matching neither); picking one representation is a
design decision, not a repair. bridge.v (cross-spec calls to functions defined
inside other modules -- illegal in Verilog whatever file set you compile) and
zerodsp_top.v (a structural wrapper the loop compiles without its five
dependencies) are the remaining two.

gen-verilog-for-simulation / icarus-simulate are deliberately left on the
source-only path, so no .trinity/icarus-baselines/ entry moves.

Verification, and its limits

• iverilog before/after on the real artifact, above. This is the load-bearing
  evidence.
• bootstrap/tests/verilog_imported_enum.rs asserts the property directly --
  every Enum_variant identifier the output USES is one it DECLARES -- on
  mac.t27, on uart.t27 as the control, and on a spec tree the test owns. Run
  against the current artifact the first and third fail (3 undeclared each) and
  the control passes, which is what a test for this defect should do.
• That test does not gate anything today. cargo test -p t27c was removed
  from corpus-ratchet in fix(corpus-ratchet): remove the t27c test step; it was measured on the wrong tree #2293 because master has 13 failing tests; per the
  note left there it should return as a ratchet, not a plain gate. Nothing in CI
  currently compiles bootstrap/tests/**.
• The change was type-checked with rustc --edition 2021 --crate-type lib --emit=metadata over compiler.rs + use_resolve.rs: identical error and
  warning set to master (one unresolved serde import, 8 warnings), and a
  deliberately planted type error in the new code was caught, so the check is
  not vacuous.

[github-actions]

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[github-actions]

PR Dashboard

Generated at: 2026-08-20 12:34:58 UTC

• fix(verilog): declare the enums a spec imports (Closes #2316) #2317 fix(verilog): declare the enums a spec imports (Closes #2316) | Created: 2026-08-20 | Updated: 2026-08-20 | 17 failing / 24 total
• fix(ci): one NOW entry per file, and retire merge=union #2298 fix(ci): one NOW entry per file, and retire merge=union | Created: 2026-08-20 | Updated: 2026-08-20 | 6 failing / 34 total
• ci: eleven merge-critical gates were silent on stacked PRs #2169 ci: eleven merge-critical gates were silent on stacked PRs | Created: 2026-08-14 | Updated: 2026-08-14 | 5 failing / 30 total
• corpus: freeze the damage, patch one class at a time, and say where one rule stops #2161 corpus: freeze the damage, patch one class at a time, and say where one rule stops | Created: 2026-08-14 | Updated: 2026-08-20 | 0 failing / 9 total
• tri triage: five ordered classes, and blocked is tested before actionable (#2156) #2157 tri triage: five ordered classes, and blocked is tested before actionable (#2156) | Created: 2026-08-14 | Updated: 2026-08-14 | 0 failing / 17 total
• parser: nesting decides the separator, never the terminator (#2127) #2151 parser: nesting decides the separator, never the terminator (#2127) | Created: 2026-08-14 | Updated: 2026-08-14 | 2 failing / 26 total
• Unbreak FPGA CI and correct two unbacked hardware claims #2081 Unbreak FPGA CI and correct two unbacked hardware claims | Created: 2026-08-11 | Updated: 2026-08-20 | 5 failing / 27 total
• feat(igla): Wave Loop 898 — module-scope [615][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1900 feat(igla): Wave Loop 898 — module-scope [615][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• chore: civilian mesh positioning — drop drone wording (bpsk.t27) #1874 chore: civilian mesh positioning — drop drone wording (bpsk.t27) | Created: 2026-08-07 | Updated: 2026-08-07 | 2 failing / 25 total
• feat(igla): Wave Loop 897 — module-scope [613][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1858 feat(igla): Wave Loop 897 — module-scope [613][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 896 — module-scope [611][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1856 feat(igla): Wave Loop 896 — module-scope [611][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 895 — module-scope [609][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1854 feat(igla): Wave Loop 895 — module-scope [609][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 894 — module-scope [607][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1852 feat(igla): Wave Loop 894 — module-scope [607][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 893 — module-scope [605][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1850 feat(igla): Wave Loop 893 — module-scope [605][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 892 — module-scope [603][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1847 feat(igla): Wave Loop 892 — module-scope [603][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 891 — module-scope [601][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1844 feat(igla): Wave Loop 891 — module-scope [601][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 0 failing / 4 total
• feat(igla): Wave Loop 890 — module-scope [599][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1842 feat(igla): Wave Loop 890 — module-scope [599][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 0 failing / 4 total
• feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1815 feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 1 total
• feat(igla): Wave Loop 882 — module-scope [583][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1813 feat(igla): Wave Loop 882 — module-scope [583][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 12 total
• feat(igla): Wave Loop 881 — module-scope [581][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1810 feat(igla): Wave Loop 881 — module-scope [581][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 12 total

Summary

Status	Count
Total Open PRs	20
PRs with Failing Checks	5
PRs with All Checks Green	15
READY	7
FAILING	5
PENDING	0

Seal Status

• ⚠️ STALE -- sha256(compiler.rs)=c3ec9fba947b != manifest seal=87e5cbd3ad94.
  The committed NMSE numbers were certified against an older compiler.rs.
  Run scripts/reseal-check.sh locally for the two-step reseal command (advisory; not a merge gate).