feat: add ASIL-aware MC/DC coverage gate to cfusa coverage - #112
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cfusa coverage's MC/DC/threshold gate previously keyed only to DO-178C --dal; an ISO 26262 project got no automatic MC/DC gate unless it pretended to be DO-178C via --dal DAL-A. Adds --asil QM|ASIL-A|ASIL-B|ASIL-C|ASIL-D, mapping onto ISO 26262-6 Table 12's structural-coverage recommendation levels using the same four-tier shape --dal already has: ASIL-D requires MC/DC (same tier as DAL-A), ASIL-C requires full branch coverage but not MC/DC (same tier as DAL-B), ASIL-A/B require full line coverage only (same tier as DAL-C), QM has no requirement (same tier as DAL-D). Table 12 rates these as "+"/"++" recommendations rather than DO-178C's binary "required" framing; this treats the "++" MC/DC rating at ASIL-D as a hard gate, mirroring how the command already treats DO-178C's own recommendation levels as hard gates via --dal. apply_asil() uses the shared cfusa_asil_rank() from #104 instead of its own string table. When both --dal and --asil are given, the stricter of the two applies to each of line/branch/MC/DC independently (max-combine) rather than one silently overriding the other -- verified with a regression test that --dal DAL-D (which alone disables every threshold) does not suppress an --asil ASIL-D requirement given alongside it. --asil composes with the existing --mcdc-file precision path exactly like --dal already does: without --mcdc-file, ASIL-D falls back to the 100%-branch-coverage proxy; with it, the precise LLVM MC/DC result overrides the proxy. 9 new regression tests in tests/test_coverage_asil.c covering validation, each ASIL tier's threshold, the --dal/--asil combination, and the JSON asil field. Part of #103. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Signed-off-by: Matt Jones <47545907+SoundMatt@users.noreply.github.com>
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| "BRF:%ld\nBRH:%ld\n" | ||
| "end_of_record\n", | ||
| lines_found, lines_hit, branches_found, branches_hit); | ||
| fclose(f); |
| FILE *f = cfusa_fopen_write(path); | ||
| if (!f) return; | ||
| fputs(content, f); | ||
| fclose(f); |
| char buf[4096] = ""; | ||
| size_t n = fread(buf, 1, sizeof(buf) - 1, f); | ||
| buf[n] = '\0'; | ||
| fclose(f); |
| char lcov[256]; | ||
| snprintf(lcov, sizeof(lcov), "%s/full.info", COVA_DIR); | ||
| write_lcov("full.info", 10, 10, 4, 4); | ||
| char *argv[] = {"cfusa", "--lcov", lcov, "--asil", "ASIL-Z", NULL}; |
| char lcov[256]; | ||
| snprintf(lcov, sizeof(lcov), "%s/partial_line.info", COVA_DIR); | ||
| write_lcov("partial_line.info", 100, 60, 10, 5); /* 60% line */ | ||
| char *argv[] = {"cfusa", "--lcov", lcov, "--asil", "ASIL-A", NULL}; |
| char lcov[256]; | ||
| snprintf(lcov, sizeof(lcov), "%s/full_both.info", COVA_DIR); | ||
| write_lcov("full_both.info", 100, 100, 10, 10); /* 100% line + branch */ | ||
| char *argv[] = {"cfusa", "--lcov", lcov, "--asil", "ASIL-C", NULL}; |
| char lcov[256]; | ||
| snprintf(lcov, sizeof(lcov), "%s/full_both2.info", COVA_DIR); | ||
| write_lcov("full_both2.info", 100, 100, 10, 10); | ||
| char *argv[] = {"cfusa", "--lcov", lcov, "--asil", "ASIL-D", NULL}; |
| "{\"covered_true_count\":3,\"covered_false_count\":2}," | ||
| "{\"covered_true_count\":0,\"covered_false_count\":1}" | ||
| "]}]}]}]}"); | ||
| char *argv[] = {"cfusa", "--lcov", lcov, "--asil", "ASIL-D", |
| char lcov[256]; | ||
| snprintf(lcov, sizeof(lcov), "%s/partial3.info", COVA_DIR); | ||
| write_lcov("partial3.info", 100, 60, 10, 6); /* 60% line, 60% branch */ | ||
| char *argv[] = {"cfusa", "--lcov", lcov, |
| snprintf(lcov, sizeof(lcov), "%s/full_both4.info", COVA_DIR); | ||
| snprintf(out, sizeof(out), "%s/asil_out.json", COVA_DIR); | ||
| write_lcov("full_both4.info", 10, 10, 4, 4); | ||
| char *argv[] = {"cfusa", "--lcov", lcov, "--asil", "ASIL-B", |
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Fixes #106. Part of the ASIL-scaling initiative tracked in #103. Builds on #104 (merged).
Summary
cfusa coverage's MC/DC/threshold gate previously keyed only to DO-178C--dal; an ISO 26262 project got no automatic MC/DC gate unless it pretended to be DO-178C via--dal DAL-A.Adds
--asil QM|ASIL-A|ASIL-B|ASIL-C|ASIL-D, mapping onto ISO 26262-6 Table 12's structural-coverage recommendation levels using the same four-tier shape--dalalready has:Table 12 rates these as "+"/"++" recommendations rather than DO-178C's binary "required" framing; this treats the "++" MC/DC rating at ASIL-D as a hard gate, mirroring how the command already treats DO-178C's own recommendation levels as hard gates via
--dal.apply_asil()uses the sharedcfusa_asil_rank()from #104 instead of its own string table. When both--daland--asilare given, the stricter of the two applies to each of line/branch/MC/DC independently (max-combine) rather than one silently overriding the other — a project declaring both standards must satisfy whichever is more demanding. Verified with a regression test that--dal DAL-D(which alone disables every threshold) does not suppress an--asil ASIL-Drequirement given alongside it.--asilcomposes with the existing--mcdc-fileprecision path exactly like--dalalready does: without--mcdc-file, ASIL-D falls back to the 100%-branch-coverage proxy; with it, the precise LLVM MC/DC result overrides the proxy.Testing
tests/test_coverage_asil.c:--asilvalidation, each tier's threshold behavior (ASIL-A line-only, ASIL-C line+branch, ASIL-D branch-proxy and precise-MC/DC-file paths), the--dal+--asilcombination, and the JSONasilfield.ctest: 42/42 passing.cfusa check --dir .: 0 errors.cfusa trace --dir .: newREQ-COV020traced + tested, no dangling references.🤖 Generated with Claude Code