Point your $PATH to a recent mainline build and run:
./mcdc.shSymptom:
Double check LLVM version:
clang version 19.0.0git (/path/to/llvm-project/clang c19436eec1c236cbe622c04e33f35f1f9478fa15)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /path/to/llvm-project/build/bin
Press any key to continue...
llvm-cov: /path/to/llvm-project/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp:591: llvm::Error llvm::coverage::CoverageMapping::loadFunctionRecord(const llvm::coverage::CoverageMappingRecord&, llvm::IndexedInstrProfReader&): Assertion `NumConds == 0' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0. Program arguments: llvm-cov "llvm-cov show" --show-mcdc main -instr-profile main.profdata -output-dir=./garbage
#0 0x00005587d0576aaf llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /path/to/llvm-project/llvm/lib/Support/Unix/Signals.inc:727:3
#1 0x00005587d057479f llvm::sys::RunSignalHandlers() /path/to/llvm-project/llvm/lib/Support/Signals.cpp:105:20
#2 0x00005587d0574af6 SignalHandler(int) /path/to/llvm-project/llvm/lib/Support/Unix/Signals.inc:413:1
#3 0x00007f1e0970a520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
#4 0x00007f1e0975e9fc __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
#5 0x00007f1e0975e9fc __pthread_kill_internal ./nptl/pthread_kill.c:78:10
#6 0x00007f1e0975e9fc pthread_kill ./nptl/pthread_kill.c:89:10
#7 0x00007f1e0970a476 gsignal ./signal/../sysdeps/posix/raise.c:27:6
#8 0x00007f1e096f07f3 abort ./stdlib/abort.c:81:7
#9 0x00007f1e096f071b _nl_load_domain ./intl/loadmsgcat.c:1177:9
#10 0x00007f1e09701e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
#11 0x00005587d060ecd2 bool llvm::DenseMapBase<llvm::DenseMap<unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>, unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>::LookupBucketFor<unsigned long>(unsigned long const&, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>> const*&) const /path/to/llvm-project/llvm/include/llvm/ADT/DenseMap.h:665:7
#12 0x00005587d060ecd2 bool llvm::DenseMapBase<llvm::DenseMap<unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>, unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>::LookupBucketFor<unsigned long>(unsigned long const&, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>*&) /path/to/llvm-project/llvm/include/llvm/ADT/DenseMap.h:689:24
#13 0x00005587d060ecd2 llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>* llvm::DenseMapBase<llvm::DenseMap<unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>, unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>::InsertIntoBucketImpl<unsigned long>(unsigned long const&, unsigned long const&, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>*) /path/to/llvm-project/llvm/include/llvm/ADT/DenseMap.h:609:22
#14 0x00005587d060ecd2 llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>* llvm::DenseMapBase<llvm::DenseMap<unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>, unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>::InsertIntoBucket<unsigned long>(llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>*, unsigned long&&) /path/to/llvm-project/llvm/include/llvm/ADT/DenseMap.h:574:37
#15 0x00005587d060ecd2 llvm::DenseMapBase<llvm::DenseMap<unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>, unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>::FindAndConstruct(unsigned long&&) /path/to/llvm-project/llvm/include/llvm/ADT/DenseMap.h:365:29
#16 0x00005587d060ecd2 llvm::DenseMapBase<llvm::DenseMap<unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>, unsigned long, llvm::SmallVector<unsigned int, 0u>, llvm::DenseMapInfo<unsigned long, void>, llvm::detail::DenseMapPair<unsigned long, llvm::SmallVector<unsigned int, 0u>>>::operator[](unsigned long&&) /path/to/llvm-project/llvm/include/llvm/ADT/DenseMap.h:369:28
#17 0x00005587d060ecd2 llvm::coverage::CoverageMapping::loadFunctionRecord(llvm::coverage::CoverageMappingRecord const&, llvm::IndexedInstrProfReader&) /path/to/llvm-project/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp:660:74
#18 0x00005587d060efd0 llvm::Error::setChecked(bool) /path/to/llvm-project/llvm/include/llvm/Support/Error.h:307:22
#19 0x00005587d060efd0 llvm::Error::operator bool() /path/to/llvm-project/llvm/include/llvm/Support/Error.h:239:15
#20 0x00005587d060efd0 llvm::coverage::CoverageMapping::loadFromReaders(llvm::ArrayRef<std::unique_ptr<llvm::coverage::CoverageMappingReader, std::default_delete<llvm::coverage::CoverageMappingReader>>>, llvm::IndexedInstrProfReader&, llvm::coverage::CoverageMapping&) /path/to/llvm-project/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp:681:71
#21 0x00005587d060f629 llvm::Error::setChecked(bool) /path/to/llvm-project/llvm/include/llvm/Support/Error.h:307:22
#22 0x00005587d060f629 llvm::Error::operator bool() /path/to/llvm-project/llvm/include/llvm/Support/Error.h:239:15
#23 0x00005587d060f629 llvm::coverage::CoverageMapping::loadFromFile(llvm::StringRef, llvm::StringRef, llvm::StringRef, llvm::IndexedInstrProfReader&, llvm::coverage::CoverageMapping&, bool&, llvm::SmallVectorImpl<llvm::SmallVector<unsigned char, 10u>>*) /path/to/llvm-project/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp:740:66
#24 0x00005587d06100cd llvm::Error::setChecked(bool) /path/to/llvm-project/llvm/include/llvm/Support/Error.h:307:22
#25 0x00005587d06100cd llvm::Error::operator bool() /path/to/llvm-project/llvm/include/llvm/Support/Error.h:239:15
#26 0x00005587d06100cd llvm::coverage::CoverageMapping::load(llvm::ArrayRef<llvm::StringRef>, llvm::StringRef, llvm::vfs::FileSystem&, llvm::ArrayRef<llvm::StringRef>, llvm::StringRef, llvm::object::BuildIDFetcher const*, bool) /path/to/llvm-project/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp:768:80
#27 0x00005587d036c352 llvm::Expected<std::unique_ptr<llvm::coverage::CoverageMapping, std::default_delete<llvm::coverage::CoverageMapping>>>::takeError() /path/to/llvm-project/llvm/include/llvm/Support/Error.h:603:15
#28 0x00005587d036c352 (anonymous namespace)::CodeCoverageTool::load() /path/to/llvm-project/llvm/tools/llvm-cov/CodeCoverage.cpp:486:41
#29 0x00005587d0370364 (anonymous namespace)::CodeCoverageTool::doShow(int, char const**, llvm::function_ref<int (int, char const**)>) (.constprop.0) /path/to/llvm-project/llvm/tools/llvm-cov/CodeCoverage.cpp:1143:3
#30 0x00005587d0376110 (anonymous namespace)::CodeCoverageTool::run((anonymous namespace)::CodeCoverageTool::Command, int, char const**) /path/to/llvm-project/llvm/tools/llvm-cov/CodeCoverage.cpp:980:18
#31 0x00005587d0376a1f showMain(int, char const**) /path/to/llvm-project/llvm/tools/llvm-cov/CodeCoverage.cpp:1348:1
#32 0x00005587d035809d std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>::~basic_string() /usr/include/c++/11/bits/basic_string.h:672:19
#33 0x00005587d035809d main /path/to/llvm-project/llvm/tools/llvm-cov/llvm-cov.cpp:82:5
#34 0x00007f1e096f1d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16
#35 0x00007f1e096f1e40 call_init ./csu/../csu/libc-start.c:128:20
#36 0x00007f1e096f1e40 __libc_start_main ./csu/../csu/libc-start.c:379:5
#37 0x00005587d0357635 _start (/path/to/llvm-project/build/bin/llvm-cov+0x27e635)
./mcdc.sh: line 26: 433149 Aborted llvm-cov show --show-mcdc $bin -instr-profile $bin.profdata -output-dir=./garbage
Point your $PATH to a patched build and run:
./mcdc.shOr you can run:
./mcdc2.shwhich outputs the results directly to the terminal. Example output:
Double check LLVM version:
clang version 19.0.0git (/path/to/llvm-project/clang cd5a33851187c872c0de7a766528be097bcc68ad)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /path/to/llvm-project/build/bin
Press any key to continue...
/users/wtj/workdir/llvm-mcdc-assertion-failure/foo.h:
1| 9|#define S_IFMT 00170000
2| |#define S_IFSOCK 0140000
3| |#define S_IFLNK 0120000
4| |#define S_IFREG 0100000
5| |#define S_IFBLK 0060000
6| |#define S_IFDIR 0040000
7| |#define S_IFCHR 0020000
8| |#define S_IFIFO 0010000
9| |#define S_ISUID 0004000
10| |#define S_ISGID 0002000
11| |#define S_ISVTX 0001000
12| |
13| |#define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
14| 18|#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
15| 9|#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
16| |#define S_ISCHR(m) (((m) & S_IFMT) == S_IFCHR)
17| |#define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
18| 1|#define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
19| 1|#define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
20| 1|
21| 1|#define S_IRWXU 00700
22| 1|#define S_IRUSR 00400
23| |#define S_IWUSR 00200
24| |#define S_IXUSR 00100
25| 1|
------------------
|---> MC/DC Decision Region (25:9) to (25:33)
|
| Number of Conditions: 3
| Condition C1 --> (25:9)
| Condition C2 --> (25:19)
| Condition C3 --> (25:28)
|
| Executed MC/DC Test Vectors:
|
| C1, C2, C3 Result
| 1 { F, -, - = F }
|
| C1-Pair: not covered
| C2-Pair: not covered
| C3-Pair: not covered
| MC/DC Coverage for Decision: 0.00%
|
------------------
26| 0|#define S_IRWXG 00070
27| 0|#define S_IRGRP 00040
28| |#define S_IWGRP 00020
29| 1|#define S_IXGRP 00010
30| 1|
31| |#define S_IRWXO 00007
32| |#define S_IROTH 00004
33| |#define S_IWOTH 00002
34| |#define S_IXOTH 00001
/users/wtj/workdir/llvm-mcdc-assertion-failure/main.c:
1| |#include "foo.h"
2| |
3| |// The example comes from https://elixir.bootlin.com/linux/v5.15.127/source/fs/open.c#L804
4| |// Note
5| |// 1. In order to trigger assertion failure, there should be one more
6| |// MCDCDecisionRegion after the ill region.
7| |// 2. Somehow in kernel the same code can trigger Clang warning
8| |//
9| |// warning: unsupported MC/DC boolean expression; contains an operation
10| |// with a nested boolean expression. Expression will not be covered
11| |//
12| |// but here we cannot unless deliberately increase the nesting level.
13| |
14| |int main(void) {
15| | int i;
16| |
17| | // *The* MCDCDecisionRegion that causes trouble
18| 10| for (i = 1; i < 10; i++) {
19| 9| if (S_ISREG(i) || S_ISDIR(i)) {
------------------
|---> MC/DC Decision Region (19:13) to (19:34)
|
| Number of Conditions: 2
| Condition C1 --> (14:20)
| Condition C2 --> (15:20)
|
| Executed MC/DC Test Vectors:
|
| C1, C2 Result
| 1 { F, F = F }
|
| C1-Pair: not covered
| C2-Pair: not covered
| MC/DC Coverage for Decision: 0.00%
|
------------------
20| 0| continue;
21| 0| }
22| 9| }
23| |
24| | // One more MCDCDecisionRegion to trigger the assertion
25| 1| if (i < 10 && i > 0 && i < 8) {
26| | return 1;
27| | }
28| |
29| | return 0;
30| |}