[clang] Assertion failure in ASTContext::getVectorType when using vector type in conditional operator #170431
Description
Link for quick verification: https://godbolt.org/z/bY61vaP1r
typedef int V __attribute__((vector_size(16)));
int main() {
V u = (V) { 0, 0, 0, 0 };
return (u ? "Nonzero!" : "Zero!");
}Clang crashes with an assertion failure when compiling code that uses a vector type directly as the condition in a conditional operator.
Stack dump:
clang-21: /workspace/install/llvm/src/llvm-project/clang/lib/AST/ASTContext.cpp:4660: clang::QualType clang::ASTContext::getVectorType(clang::QualType, unsigned int, clang::VectorKind) const: Assertion `vecType->isBuiltinType() || (vecType->isBitIntType() && llvm::isPowerOf2_32(vecType->castAs<BitIntType>()->getNumBits()))' failed.
Stack dump:
0. Program arguments: /workspace/install/llvm/build_21.1.4/bin/clang-21 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -main-file-name 4854.fuzz -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/workspace/exps -fcoverage-compilation-dir=/workspace/exps -resource-dir /workspace/install/llvm/build_21.1.4/lib/clang/21 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/13/../../../../include/x86_64-linux-gnu/c++/13 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/backward -internal-isystem /workspace/install/llvm/build_21.1.4/lib/clang/21/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/13/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -std=c++20 -fdeprecated-macro -ferror-limit 19 -fmessage-length=125 -fgnuc-version=4.2.1 -fno-implicit-modules -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/4854-e4dd6a.o -x c++ /workspace/exps/featurefuzz/generate_feature_fine_tuning_qwen_4b_input_2_feature_1_exp/cases/4854.fuzz
1. /workspace/exps/featurefuzz/generate_feature_fine_tuning_qwen_4b_input_2_feature_1_exp/cases/4854.fuzz:36:34: current parser token ')'
2. /workspace/exps/featurefuzz/generate_feature_fine_tuning_qwen_4b_input_2_feature_1_exp/cases/4854.fuzz:12:12: parsing function body 'main'
3. /workspace/exps/featurefuzz/generate_feature_fine_tuning_qwen_4b_input_2_feature_1_exp/cases/4854.fuzz:12:12: in compound statement ('{}')
4. /workspace/exps/featurefuzz/generate_feature_fine_tuning_qwen_4b_input_2_feature_1_exp/cases/4854.fuzz:35:9: in compound statement ('{}')
#0 0x00005c34b0f30c2a llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0x9691c2a)
#1 0x00005c34b0f31457 PrintStackTraceSignalHandler(void*) Signals.cpp:0:0
#2 0x00005c34b0f2af57 llvm::sys::RunSignalHandlers() (/workspace/install/llvm/build_21.1.4/bin/clang-21+0x968bf57)
#3 0x00005c34b0f2b1c7 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
#4 0x00007e9b0b483330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
#5 0x00007e9b0b4dcb2c __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
#6 0x00007e9b0b4dcb2c __pthread_kill_internal ./nptl/pthread_kill.c:78:10
#7 0x00007e9b0b4dcb2c pthread_kill ./nptl/pthread_kill.c:89:10
#8 0x00007e9b0b48327e raise ./signal/../sysdeps/posix/raise.c:27:6
#9 0x00007e9b0b4668ff abort ./stdlib/abort.c:81:7
#10 0x00007e9b0b46681b _nl_load_domain ./intl/loadmsgcat.c:1177:9
#11 0x00007e9b0b479517 (/lib/x86_64-linux-gnu/libc.so.6+0x3b517)
#12 0x00005c34b5a37d1f clang::ASTContext::getVectorType(clang::QualType, unsigned int, clang::VectorKind) const (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xe198d1f)
#13 0x00005c34b4cfe98f clang::Sema::CheckVectorConditionalTypes(clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::SourceLocation) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xd45f98f)
#14 0x00005c34b4d0baaf clang::Sema::CXXCheckConditionalOperands(clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::ExprValueKind&, clang::ExprObjectKind&, clang::SourceLocation) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xd46caaf)
#15 0x00005c34b4c0ad7b clang::Sema::CheckConditionalOperands(clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::ExprValueKind&, clang::ExprObjectKind&, clang::SourceLocation) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xd36bd7b)
#16 0x00005c34b4c0cd4a clang::Sema::ActOnConditionalOp(clang::SourceLocation, clang::SourceLocation, clang::Expr*, clang::Expr*, clang::Expr*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xd36dd4a)
#17 0x00005c34b44c9258 clang::Parser::ParseRHSOfBinaryExpression(clang::ActionResult<clang::Expr*, true>, clang::prec::Level) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc2a258)
#18 0x00005c34b44c31ac clang::Parser::ParseAssignmentExpression(clang::TypoCorrectionTypeBehavior) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc241ac)
#19 0x00005c34b44c36cd clang::Parser::ParseExpressionList(llvm::SmallVectorImpl<clang::Expr*>&, llvm::function_ref<void ()>, bool) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc246cd)
#20 0x00005c34b44c590e clang::Parser::ParsePostfixExpressionSuffix(clang::ActionResult<clang::Expr*, true>) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc2690e)
#21 0x00005c34b44bf92b clang::Parser::ParseCastExpression(clang::CastParseKind, bool, bool&, clang::TypoCorrectionTypeBehavior, bool, bool*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc2092b)
#22 0x00005c34b44c30d1 clang::Parser::ParseCastExpression(clang::CastParseKind, bool, clang::TypoCorrectionTypeBehavior, bool, bool*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc240d1)
#23 0x00005c34b44c3194 clang::Parser::ParseAssignmentExpression(clang::TypoCorrectionTypeBehavior) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc24194)
#24 0x00005c34b44c4a15 clang::Parser::ParseExpression(clang::TypoCorrectionTypeBehavior) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcc25a15)
#25 0x00005c34b457d257 clang::Parser::ParseExprStatement(clang::Parser::ParsedStmtContext) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xccde257)
#26 0x00005c34b457f487 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&, clang::ParsedAttributes&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce0487)
#27 0x00005c34b4580099 clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce1099)
#28 0x00005c34b4581e9e clang::Parser::ParseCompoundStatementBody(bool) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce2e9e)
#29 0x00005c34b45827d0 void llvm::function_ref<void ()>::callback_fn<clang::Parser::ParseCompoundStatement(bool, unsigned int)::'lambda'()>(long) ParseStmt.cpp:0:0
#30 0x00005c34b694442b clang::StackExhaustionHandler::runWithSufficientStackSpace(clang::SourceLocation, llvm::function_ref<void ()>) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xf0a542b)
#31 0x00005c34b4575e0e clang::Parser::ParseCompoundStatement(bool, unsigned int) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xccd6e0e)
#32 0x00005c34b457e9c7 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&, clang::ParsedAttributes&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xccdf9c7)
#33 0x00005c34b4580099 clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce1099)
#34 0x00005c34b4582ad1 clang::Parser::ParseStatement(clang::SourceLocation*, clang::Parser::ParsedStmtContext) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce3ad1)
#35 0x00005c34b4587335 clang::Parser::ParseIfStatement(clang::SourceLocation*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce8335)
#36 0x00005c34b457e855 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&, clang::ParsedAttributes&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xccdf855)
#37 0x00005c34b4580099 clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce1099)
#38 0x00005c34b4581e9e clang::Parser::ParseCompoundStatementBody(bool) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce2e9e)
#39 0x00005c34b45828c2 clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcce38c2)
#40 0x00005c34b4426337 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcb87337)
#41 0x00005c34b447fd18 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcbe0d18)
#42 0x00005c34b441c307 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcb7d307)
#43 0x00005c34b441ce9e clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcb7de9e)
#44 0x00005c34b4428f98 clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcb89f98)
#45 0x00005c34b442a59d clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcb8b59d)
#46 0x00005c34b44109d0 clang::ParseAST(clang::Sema&, bool, bool) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xcb719d0)
#47 0x00005c34b215892b clang::ASTFrontendAction::ExecuteAction() (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xa8b992b)
#48 0x00005c34b1d46360 clang::CodeGenAction::ExecuteAction() (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xa4a7360)
#49 0x00005c34b21609cf clang::FrontendAction::Execute() (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xa8c19cf)
#50 0x00005c34b20a6f46 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xa807f46)
#51 0x00005c34b22e8f7b clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0xaa49f7b)
#52 0x00005c34ac057523 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0x47b8523)
#53 0x00005c34ac047c58 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#54 0x00005c34ac04db28 clang_main(int, char**, llvm::ToolContext const&) (/workspace/install/llvm/build_21.1.4/bin/clang-21+0x47aeb28)
#55 0x00005c34abea8b4a main (/workspace/install/llvm/build_21.1.4/bin/clang-21+0x4609b4a)
#56 0x00007e9b0b4681ca __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
#57 0x00007e9b0b46828b call_init ./csu/../csu/libc-start.c:128:20
#58 0x00007e9b0b46828b __libc_start_main ./csu/../csu/libc-start.c:347:5
#59 0x00005c34ac045f55 _start (/workspace/install/llvm/build_21.1.4/bin/clang-21+0x47a6f55)
clang++: error: unable to execute command: Aborted (core dumped)
Clang version:
clang version 21.1.4 (https://github.com/llvm/llvm-project.git 222fc11f2b8f25f6a0f4976272ef1bb7bf49521d)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /workspace/install/llvm/build_21.1.4/bin
Build config: +assertions
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/13
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/13
Candidate multilib: .;@m64
Selected multilib: .;@m64