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7 commits

Author SHA1 Message Date
Gergo Magyar
5165d71d7b fix(cfg): harvest C++ structured-binding defs (auto [a,b]=e) (#2195)
The C++ def/use harvester only recorded a def when an init_declarator's
declarator was a plain identifier, so a structured binding (auto [a,b] = mk(),
incl. the auto& reference form whose binding sits under a reference_declarator)
declared only the first name in phase 1 and emitted ZERO defs in phase 2 — a,b
were walked as spurious uses and later use(a)/use(b) resolved to a synthetic
module binding, silently corrupting REACHING_DEF/taint for an idiomatic C++17
shape. Unwrap the structured_binding_declarator in both phases and def every
identifier leaf; result-of-initializer flows to the whole list. Inert for C
(no structured bindings). Characterization tests added (plain + reference form).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 18:39:28 +00:00
Gergo Magyar
213ae2526e style(cfg): apply prettier + drop unused imports across the PDG files (#2195)
The merge of main into this branch pulled in the stricter quality gates
(prettier --check . and eslint .), which surfaced pre-existing formatting in the
PDG/CFG rollout (line-width wrapping across the visitor + harvest files, bench,
tests) plus 9 no-unused-imports errors. Mechanical autofix only — npm run
format + lint:fix equivalent, scoped to gitnexus/: removes unused FunctionCfg/
SiteRecord type imports left by the U8 helper consolidation and stale
FinalizerFrame imports in python.ts/ruby.ts. No behavior change: tsc clean, cfg
unit suite 617 passed, eslint 0 errors. (gitnexus-web class-order noise is a
local tailwind-plugin artifact CI does not flag — left untouched.)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 17:29:48 +00:00
Gergo Magyar
f47e952ba1 test(cfg): consolidate copied visitor-test helpers into cfg-harness (#2195 U8)
The 13 *-visitor.test.ts files each copied a byte-identical set of CFG-shape
helpers (edgeKinds/block/reaches/reachable/bindingIdx/allSites/hasAnySites,
~380 lines total). Export them once from test/helpers/cfg-harness.ts and import
per file (only the subset each references). Also drop each file's local
exitReachableFromAll — a re-implementation of the production
isExitReachableFromAllBlocks (semantically identical: false iff some
entry-reachable non-EXIT block can't reach EXIT) — and point its live call
sites at the already-imported production function. Pure test-only mechanical
move, behavior-preserving: tsc clean, test/unit/cfg/ 613 passed unchanged.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 16:54:45 +00:00
Gergo Magyar
3f17cb7fd5 test(cfg): isolate the non-terminating-loop hazard in worker CDG asserts (#2195 U3)
The pipeline-pdg worker-mode blocks asserted a whole-fixture cdg>0
aggregate (satisfied by any branching fn) while the comment claimed it
proved the non-terminating-loop EXIT-reachability end-to-end. Add a per-
language `hazard` marker + isolate the assertion: locate the hazard
function's BasicBlocks by its anchor and assert >=1 CDG edge is sourced
within it (a marker mutation now fails the test — non-vacuous). C# keeps
the aggregate (its fixture has no infinite loop). Comments corrected.

Switch the 7 visitor unit tests (java/csharp/dart/kotlin/php/swift/c-cpp)
from the local exitReachableFromAll CFG-shape helper to the production
isExitReachableFromAllBlocks + computeControlDependence on the hazard
function, matching go/python/ruby/rust/vue. 241 unit + 30 pipeline green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 16:16:12 +00:00
Gergo Magyar
bbee2da92e fix(cfg): synthetic-escape pass restores CDG for exit-unreachable cycles (#2195 U1)
Unconditional goto-cycles (C/C++/C#/Go) wire a backward seq edge with no
structural exit-escape edge, so EXIT becomes non-reverse-reachable and
emitFileCdg silently skipped ALL control-dependence for the function.

New cfg/synthetic-escape.ts: a pure deterministic SCC routine (iterative
Tarjan, sorted adjacency) + augmentForPostDom(cfg). No-op when EXIT is
already reverse-reachable (terminating fns + visitor-escaped loops are
byte-identical — returns the same object). Otherwise it batch-bridges
every exit-less SCC by adding an ANALYSIS-ONLY escape edge from the SCC's
controlling block (highest out-degree branch; lowest-index tie-break) to
EXIT, on a shallow-cloned FunctionCfg — never mutating persisted
cfg.edges. emitFileCdg threads that augmented view through BOTH
isExitReachableFromAllBlocks AND computeControlDependence (the Ferrante
walk re-reads cfg.edges, so a tree-only augmentation would be wrong).

Precision (anti-masking): only a trapped region containing a control
point (>=2-successor block) is bridged — a branch-less trapped region
carries no recoverable control-dependence and is indistinguishable from a
genuine construction anomaly, so it stays on the skip path (the existing
disconnected-block skip test still skips, skippedUnsoundFunctions===1). A
residual non-cycle dangling block is never bridged.

repro `void handler(int a){ start: if(a>0){work();} goto start; }`:
before exitReachable=false/CDG=0 → after one synthetic 2->1 edge,
exitReachable=true, exact CDG = {2->2:T,2->2:F,2->3:T,2->4:T,2->4:F}
(pinned exactly, not CDG>0 — catches a wrong representative). AC2 property
test extended to the augmented graph; per-language goto-cycle regressions
(C/C++/C#/Go). 199 cfg tests green; bench --check fingerprints unchanged
(analysis-only, zero persisted drift).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 15:58:50 +00:00
Gergo Magyar
b294a387a5 feat(cfg): call-site sites[] taint substrate for C-family (#2195 U6)
Extend the C/C++/C#/Java/Go harvests with the call-site sites[] taint
substrate (SiteRecord/SiteArgOccurrence), mirroring the TS shape so the
shared taint matcher consumes all languages uniformly. Extract the
grammar-agnostic site machinery into cfg/visitors/call-site-harvest.ts
(CallSiteFactAccumulator -- names no language); each harvest adds only its
per-grammar visitCall/walkChain over its call node (C/C++ call_expression,
C# invocation_expression, Java method_invocation, Go call_expression).

INERT BY DESIGN: no C-family taint model exists (registerBuiltinTaintModels
is TS/JS only), so getSourceSinkConfig returns undefined for these
languages and the harvested sites produce ZERO TAINTED edges -- the
positive source->sink->TAINTED path is deferred with the model authoring.

sites emitted only when non-empty; facts-only attachment, block/edge
topology unchanged (pre-existing topology + def/use tests byte-identical).
23 new substrate tests; 574 green across the cfg/taint/emit suites; gate
green; tsc clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 11:56:21 +00:00
Gergo Magyar
018635074a feat(cfg): C and C++ CFG visitor + def/use harvest (#2195 U2)
Add createCCfgVisitor/createCppCfgVisitor over a shared CCfgWalk core.
Grammar introspection confirmed tree-sitter-c and tree-sitter-cpp share
every control-flow node type/field, so CppCfgWalk extends CCfgWalk with
only the C++-only nodes (try/catch/throw/for_range_loop/lambda) via a
visitExtra hook -- no language conditionals (AGENTS no-language-naming).
Wire both into c-cpp.ts providers.

Harvest (c-cpp-harvest.ts): two-phase binding table + per-statement
defs/uses/mayDefs (no sites[] yet -- U6). Edge kinds match the TS
contract; functionStartColumn populated; non-terminating loops (for(;;),
while(1)) emit the structural exit-escape edge so EXIT stays
reverse-reachable and CDG is not silently skipped -- verified against the
production post-dominator + control-dependence solvers (for(;;) -> 3 CDG
edges). buildFunctionCfg returns undefined rather than throwing.

23 real-parser regression tests; grammar-literal gate green (literals
validated against both grammars). Documented gaps: C++ RAII destructors,
setjmp/longjmp, computed goto (route to EXIT + warn).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 10:59:00 +00:00