It appears to be a recent regression. [633] % clangtk -v clang version 14.0.0 (https://github.com/llvm/llvm-project.git 26be7fe27c66a4db21ca2290ade10b171513177f) Target: x86_64-unknown-linux-gnu Thread model: posix InstalledDir: /local/suz-local/opfuzz/bin Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/8 Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6 Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.5.0 Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7 Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0 Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8 Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0 Candidate multilib: .;@m64 Selected multilib: .;@m64 [634] % [634] % clangtk -O1 small.c [635] % [635] % clangtk -Os small.c clang-14: /local/suz-local/software/clangbuild/llvm-project/llvm/include/llvm/ADT/ArrayRef.h:169: const T& llvm::ArrayRef<T>::front() const [with T = llvm::Value*]: Assertion `!empty()' failed. PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script. Stack dump: 0. Program arguments: /local/suz-local/software/local/clang-trunk/bin/clang-14 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj --mrelax-relocations -disable-free -main-file-name small.c -mrelocation-model static -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/home/suz -resource-dir /local/suz-local/software/local/clang-trunk/lib/clang/14.0.0 -I /usr/local/include/csmith -I /local/suz-local/software/local/include -internal-isystem /local/suz-local/software/local/clang-trunk/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Os -fdebug-compilation-dir=/home/suz -ferror-limit 19 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/small-374d0a.o -x c small.c 1. <eof> parser at end of file 2. Optimizer #0 0x0000558218505c4f PrintStackTraceSignalHandler(void*) Signals.cpp:0:0 #1 0x00005582185033fd SignalHandler(int) Signals.cpp:0:0 #2 0x00007ff0f83bb8a0 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x128a0) #3 0x00007ff0f706cf47 raise /build/glibc-2ORdQG/glibc-2.27/signal/../sysdeps/unix/sysv/linux/raise.c:51:0 #4 0x00007ff0f706e8b1 abort /build/glibc-2ORdQG/glibc-2.27/stdlib/abort.c:81:0 #5 0x00007ff0f705e42a __assert_fail_base /build/glibc-2ORdQG/glibc-2.27/assert/assert.c:89:0 #6 0x00007ff0f705e4a2 (/lib/x86_64-linux-gnu/libc.so.6+0x304a2) #7 0x0000558218740306 llvm::slpvectorizer::BoUpSLP::getEntryCost(llvm::slpvectorizer::BoUpSLP::TreeEntry const*, llvm::ArrayRef<llvm::Value*>) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3c03306) #8 0x000055821875b1e2 llvm::slpvectorizer::BoUpSLP::getTreeCost(llvm::ArrayRef<llvm::Value*>) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3c1e1e2) #9 0x000055821875d111 llvm::SLPVectorizerPass::tryToVectorizeList(llvm::ArrayRef<llvm::Value*>, llvm::slpvectorizer::BoUpSLP&, bool) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3c20111) #10 0x0000558218762b30 llvm::SLPVectorizerPass::vectorizeChainsInBlock(llvm::BasicBlock*, llvm::slpvectorizer::BoUpSLP&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3c25b30) #11 0x00005582187659bc llvm::SLPVectorizerPass::runImpl(llvm::Function&, llvm::ScalarEvolution*, llvm::TargetTransformInfo*, llvm::TargetLibraryInfo*, llvm::AAResults*, llvm::LoopInfo*, llvm::DominatorTree*, llvm::AssumptionCache*, llvm::DemandedBits*, llvm::OptimizationRemarkEmitter*) (.part.2032) SLPVectorizer.cpp:0:0 #12 0x00005582187669cb llvm::SLPVectorizerPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3c299cb) #13 0x00005582196c4b41 llvm::detail::PassModel<llvm::Function, llvm::SLPVectorizerPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x4b87b41) #14 0x0000558217cd2f2c llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3195f2c) #15 0x00005582162a8cf1 llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function> >, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x176bcf1) #16 0x0000558217cd2814 llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3195814) #17 0x00005582162a96f1 llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module> >::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x176c6f1) #18 0x0000558217cd0fd4 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module> >::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3193fd4) #19 0x00005582188074b4 (anonymous namespace)::EmitAssemblyHelper::EmitAssemblyWithNewPassManager(clang::BackendAction, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream> >) BackendUtil.cpp:0:0 #20 0x000055821880c3f3 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream> >) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x3ccf3f3) #21 0x00005582194f6d4a clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x49b9d4a) #22 0x000055821a3cf659 clang::ParseAST(clang::Sema&, bool, bool) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x5892659) #23 0x00005582194f6ee8 clang::CodeGenAction::ExecuteAction() (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x49b9ee8) #24 0x0000558218e440f1 clang::FrontendAction::Execute() (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x43070f1) #25 0x0000558218de03ca clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x42a33ca) #26 0x0000558218f1374a clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x43d674a) #27 0x000055821601768c cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x14da68c) #28 0x0000558216012a39 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) driver.cpp:0:0 #29 0x0000558215f406b6 main (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x14036b6) #30 0x00007ff0f704fb97 __libc_start_main /build/glibc-2ORdQG/glibc-2.27/csu/../csu/libc-start.c:344:0 #31 0x00005582160125aa _start (/local/suz-local/software/local/clang-trunk/bin/clang-14+0x14d55aa) clang-14: error: unable to execute command: Aborted clang-14: error: clang frontend command failed due to signal (use -v to see invocation) clang version 14.0.0 (https://github.com/llvm/llvm-project.git 26be7fe27c66a4db21ca2290ade10b171513177f) Target: x86_64-unknown-linux-gnu Thread model: posix InstalledDir: /local/suz-local/opfuzz/bin clang-14: note: diagnostic msg: ******************** PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT: Preprocessed source(s) and associated run script(s) are located at: clang-14: note: diagnostic msg: /tmp/small-e70097.c clang-14: note: diagnostic msg: /tmp/small-e70097.sh clang-14: note: diagnostic msg: ******************** [636] % [636] % cat small.c int printf (const char *, ...); int a, b; #pragma pack(1) struct { int c : 4; volatile int d : 9; int : 7; int e : 23; int f : 25; } g, h, i, j; volatile int k; int main() { while (b) { g.d; int l = h.f ^ i.e ^ j.c; if (a) printf("%d", a); j.f = l; g.f && k; } return 0; }
This was noted by someone else just a bit earlier. Patch review underway here: https://reviews.llvm.org/D107058
For reference, the bug was probably uncovered by this patch: https://reviews.llvm.org/D105020 / https://reviews.llvm.org/rGe408d1dfab42b27d0aa51b221
> This was noted by someone else just a bit earlier. Okay, yes, this crash seems to be quite easy to trigger. > Patch review underway here: > https://reviews.llvm.org/D107058 Great; thanks, Sanjay!
Should be fixed with: https://reviews.llvm.org/rGc2deb2afafee991c06cc9 I don't think the bug was visible in the 13.0 release, so I'm resolving as fixed. Please reopen if that's not correct.
I checked all the triggering tests I have; all good. Thanks, Sanjay!