There is a valid C program which crashes clang version 8.0 - 11.0 (https://godbolt.org/z/3T8ePj). It also triggers an assertion `Result && "Could not evaluate expression"' failed in trunk. I attached the output of trunk version below (the stdio.h including and printf can be reduced). $ cat test.c #include <stdio.h> long a() { return 0; } int main() { int b = 1, c = 2; int d = __builtin_choose_expr(__builtin_expect(({ 0; }), a()), b, c); printf("%d\n", d); } $ cat /tmp/test-fb042e.sh # Crash reproducer for clang version 12.0.0 (https://github.com/llvm/llvm-project.git b46924ee5afe234526220c29a497794bf65f8f7f) # Driver args: "-c" "test.c" # Original command: "/data/xxx/git/llvm-project/build_12/bin/clang-12" "-cc1" "-triple" "x86_64-unknown-linux-gnu" "-emit-obj" "-mrelax-all" "--mrelax-relocations" "-disable-free" "-main-file-name" "test.c" "-mrelocation-model" "static" "-mframe-pointer=all" "-fmath-errno" "-fno-rounding-math" "-mconstructor-aliases" "-munwind-tables" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-fno-split-dwarf-inlining" "-debugger-tuning=gdb" "-resource-dir" "/data/xxx/git/llvm-project/build_12/lib/clang/12.0.0" "-internal-isystem" "/usr/local/include" "-internal-isystem" "/data/xxx/git/llvm-project/build_12/lib/clang/12.0.0/include" "-internal-externc-isystem" "/usr/include/x86_64-linux-gnu" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-fdebug-compilation-dir" "/data/xxx/docker_share/clang" "-ferror-limit" "19" "-fgnuc-version=4.2.1" "-fcolor-diagnostics" "-faddrsig" "-o" "test.o" "-x" "c" "test.c" "/data/xxx/git/llvm-project/build_12/bin/clang-12" "-cc1" "-triple" "x86_64-unknown-linux-gnu" "-emit-obj" "-mrelax-all" "--mrelax-relocations" "-disable-free" "-main-file-name" "test.c" "-mrelocation-model" "static" "-mframe-pointer=all" "-fmath-errno" "-fno-rounding-math" "-mconstructor-aliases" "-munwind-tables" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-fno-split-dwarf-inlining" "-debugger-tuning=gdb" "-ferror-limit" "19" "-fgnuc-version=4.2.1" "-fcolor-diagnostics" "-faddrsig" "-x" "c" "test-fb042e.c" $ ./clang -c test.c clang: /data/xxx/git/llvm-project/clang/lib/AST/ExprConstant.cpp:14979: llvm::APSInt clang::Expr::EvaluateKnownConstIntCheckOverflow(const clang::ASTContext &, SmallVectorImpl<clang::PartialDiagnosticAt> *) const: Assertion `Result && "Could not evaluate expression"' 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: /data/xxx/git/llvm-project/build_12/bin/clang -c test.c 1. test.c:7:73: current parser token ';' 2. test.c:5:12: parsing function body 'main' 3. test.c:5:12: in compound statement ('{}') #0 0x0000000000d89891 __interceptor_backtrace.part.117 (/data/xxx/git/llvm-project/build_12/bin/clang+0xd89891) #1 0x000000000d59d8da llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /data/xxx/git/llvm-project/llvm/lib/Support/Unix/Signals.inc:561:7 #2 0x000000000d594061 llvm::sys::RunSignalHandlers() /data/xxx/git/llvm-project/llvm/lib/Support/Signals.cpp:72:18 #3 0x000000000d59a4ff llvm::sys::CleanupOnSignal(unsigned long) /data/xxx/git/llvm-project/llvm/lib/Support/Unix/Signals.inc:0:3 #4 0x000000000d2b2385 (anonymous namespace)::CrashRecoveryContextImpl::HandleCrash(int, unsigned long) /data/xxx/git/llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:75:5 #5 0x000000000d2b2e4c CrashRecoverySignalHandler(int) /data/xxx/git/llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:389:1 #6 0x00007f74347648a0 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x128a0) #7 0x00007f7434187f47 raise /build/glibc-2ORdQG/glibc-2.27/signal/../sysdeps/unix/sysv/linux/raise.c:51:0 #8 0x00007f74341898b1 abort /build/glibc-2ORdQG/glibc-2.27/stdlib/abort.c:81:0 #9 0x00007f743417942a __assert_fail_base /build/glibc-2ORdQG/glibc-2.27/assert/assert.c:89:0 #10 0x00007f74341794a2 (/lib/x86_64-linux-gnu/libc.so.6+0x304a2) #11 0x000000001d435f84 clang::Expr::EvaluateKnownConstIntCheckOverflow(clang::ASTContext const&, llvm::SmallVectorImpl<std::pair<clang::SourceLocation, clang::PartialDiagnostic> >*) const /data/xxx/git/llvm-project/clang/lib/AST/ExprConstant.cpp:0:3 #12 0x000000001962daf7 llvm::APSInt::operator=(llvm::APSInt&&) /data/xxx/git/llvm-project/llvm/include/llvm/ADT/APSInt.h:0:0 #13 0x000000001962daf7 clang::Sema::VerifyIntegerConstantExpression(clang::Expr*, llvm::APSInt*, clang::Sema::VerifyICEDiagnoser&, clang::Sema::AllowFoldKind) /data/xxx/git/llvm-project/clang/lib/Sema/SemaExpr.cpp:16139:0 #14 0x000000001961f7b9 clang::Sema::VerifyIntegerConstantExpression(clang::Expr*, llvm::APSInt*, unsigned int, clang::Sema::AllowFoldKind) /data/xxx/git/llvm-project/clang/lib/Sema/SemaExpr.cpp:16041:10 #15 0x000000001961f7b9 clang::Sema::ActOnChooseExpr(clang::SourceLocation, clang::Expr*, clang::Expr*, clang::Expr*, clang::SourceLocation) /data/xxx/git/llvm-project/clang/lib/Sema/SemaExpr.cpp:15135:0 #16 0x00000000180fc5b2 clang::Parser::ParseBuiltinPrimaryExpression() /data/xxx/git/llvm-project/clang/lib/Parse/ParseExpr.cpp:2608:19 #17 0x00000000180da7f1 clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, bool&, clang::Parser::TypeCastState, bool, bool*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseExpr.cpp:1309:12 #18 0x00000000180c5564 clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, clang::Parser::TypeCastState, bool, bool*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseExpr.cpp:681:20 #19 0x00000000180c5564 clang::Parser::ParseAssignmentExpression(clang::Parser::TypeCastState) /data/xxx/git/llvm-project/clang/lib/Parse/ParseExpr.cpp:173:0 #20 0x0000000017fffcab clang::Parser::ParseInitializer() /data/xxx/git/llvm-project/clang/include/clang/Parse/Parser.h:0:14 #21 0x0000000017fffcab clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseDecl.cpp:2302:0 #22 0x0000000017ff7169 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseDecl.cpp:2038:21 #23 0x0000000017fe141c clang::Parser::ParseSimpleDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::Parser::ParsedAttributesWithRange&, bool, clang::Parser::ForRangeInit*, clang::SourceLocation*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseDecl.cpp:1754:10 #24 0x0000000017fe043f clang::Parser::ParseDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::Parser::ParsedAttributesWithRange&, clang::SourceLocation*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseDecl.cpp:1687:12 #25 0x0000000018293d42 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::Parser::ParsedAttributesWithRange&) /data/xxx/git/llvm-project/clang/lib/Parse/ParseStmt.cpp:0:16 #26 0x000000001829089a clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseStmt.cpp:106:20 #27 0x00000000182af9e5 clang::Parser::ParseCompoundStatementBody(bool) /data/xxx/git/llvm-project/clang/lib/Parse/ParseStmt.cpp:1099:11 #28 0x00000000182b580f clang::ActionResult<clang::Stmt*, true>::isInvalid() const /data/xxx/git/llvm-project/clang/include/clang/Sema/Ownership.h:0:0 #29 0x00000000182b580f clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) /data/xxx/git/llvm-project/clang/lib/Parse/ParseStmt.cpp:2263:0 #30 0x0000000017f77add clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) /data/xxx/git/llvm-project/clang/lib/Parse/Parser.cpp:0:10 #31 0x0000000017ff6aa0 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) /data/xxx/git/llvm-project/clang/lib/Parse/ParseDecl.cpp:1976:27 #32 0x0000000017f737b2 clang::Parser::ParseDeclOrFunctionDefInternal(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec&, clang::AccessSpecifier) /data/xxx/git/llvm-project/clang/lib/Parse/Parser.cpp:1134:10 #33 0x0000000017f705d7 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*, clang::AccessSpecifier) /data/xxx/git/llvm-project/clang/lib/Parse/Parser.cpp:1150:12 #34 0x0000000017f6d3ad clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*) /data/xxx/git/llvm-project/clang/lib/Parse/Parser.cpp:0:12 #35 0x0000000017f662ee clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, bool) /data/xxx/git/llvm-project/clang/lib/Parse/Parser.cpp:716:10 #36 0x0000000017f52b99 clang::ParseAST(clang::Sema&, bool, bool) /data/xxx/git/llvm-project/clang/lib/Parse/ParseAST.cpp:157:15 #37 0x00000000102ed733 clang::ASTFrontendAction::ExecuteAction() /data/xxx/git/llvm-project/clang/lib/Frontend/FrontendAction.cpp:1058:1 #38 0x00000000129dd448 clang::CodeGenAction::ExecuteAction() /data/xxx/git/llvm-project/clang/lib/CodeGen/CodeGenAction.cpp:1082:30 #39 0x00000000102ea56d clang::FrontendAction::Execute() /data/xxx/git/llvm-project/clang/lib/Frontend/FrontendAction.cpp:0:8 #40 0x00000000100f5a87 llvm::Error::operator bool() /data/xxx/git/llvm-project/llvm/include/llvm/Support/Error.h:0:0 #41 0x00000000100f5a87 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /data/xxx/git/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:949:0 #42 0x00000000107e829e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /data/xxx/git/llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:278:25 #43 0x0000000000e277af cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /data/xxx/git/llvm-project/clang/tools/driver/cc1_main.cpp:240:15 #44 0x0000000000e0f567 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) /data/xxx/git/llvm-project/clang/tools/driver/driver.cpp:330:12 #45 0x000000000fc7c44d clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const::$_1::operator()() const /data/xxx/git/llvm-project/clang/lib/Driver/Job.cpp:404:30 #46 0x000000000fc7c44d void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const::$_1>(long) /data/xxx/git/llvm-project/llvm/include/llvm/ADT/STLExtras.h:185:0 #47 0x000000000d2b1f24 llvm::function_ref<void ()>::operator()() const /data/xxx/git/llvm-project/llvm/include/llvm/ADT/STLExtras.h:209:12 #48 0x000000000d2b1f24 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) /data/xxx/git/llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:424:0 #49 0x000000000fc79da2 clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const /data/xxx/git/llvm-project/clang/lib/Driver/Job.cpp:404:7 #50 0x000000000fb7111e clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&) const /data/xxx/git/llvm-project/clang/lib/Driver/Compilation.cpp:195:15 #51 0x000000000fb71d6c clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) const /data/xxx/git/llvm-project/clang/lib/Driver/Compilation.cpp:248:19 #52 0x000000000fbd4e2a llvm::SmallVectorBase<unsigned int>::empty() const /data/xxx/git/llvm-project/llvm/include/llvm/ADT/SmallVector.h:0:0 #53 0x000000000fbd4e2a clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) /data/xxx/git/llvm-project/clang/lib/Driver/Driver.cpp:1517:0 #54 0x0000000000e0c4af main /data/xxx/git/llvm-project/clang/tools/driver/driver.cpp:502:21 #55 0x00007f743416ab97 __libc_start_main /build/glibc-2ORdQG/glibc-2.27/csu/../csu/libc-start.c:344:0 #56 0x0000000000d072ca _start (/data/xxx/git/llvm-project/build_12/bin/clang+0xd072ca) clang-12: error: clang frontend command failed with exit code 134 (use -v to see invocation) clang version 12.0.0 (https://github.com/llvm/llvm-project.git b46924ee5afe234526220c29a497794bf65f8f7f) Target: x86_64-unknown-linux-gnu Thread model: posix InstalledDir: /data/xxx/git/llvm-project/build_12/bin clang-12: note: diagnostic msg: ******************** PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT: Preprocessed source(s) and associated run script(s) are located at: clang-12: note: diagnostic msg: /tmp/test-fb042e.c clang-12: note: diagnostic msg: /tmp/test-fb042e.sh clang-12: note: diagnostic msg: ********************
It seems that the program compiled by trunk has an invalid output. The valid output should be 2 (where d = c = 2). For trunk, it prints 1 (https://godbolt.org/z/njo3Gj). For clang 6.0.0 and 7.0.0, it prints 2 (https://godbolt.org/z/8re8cG). For GCC, it prints 2 (https://godbolt.org/z/Wfodrr).
I somehow feel it is serious, as trunk mis-compiles the program. I can understand the second argument of __builtin_expect should be an integer instead of function invocation according to the standard. But without warning, it will cause a problem. So I want to change the importance to 'release blocker'. However, I am not so sure whether it worths the effort. I do apologize in advance for any inconvenience caused. Thanks!
Further reduced: int main() { return __builtin_choose_expr(__builtin_expect(({0;}), 0), 1, 2); } If we reduce further to return __builtin_choose_expr(({0;}), 1, 2); ... then Clang and GCC both reject saying that the statement-expression is not a constant expression. Similarly: int maybe_vla(int n) { goto label; int arr[({0;})]; label: return sizeof(arr); } ... is rejected by both Clang and GCC because the statement-expression is not an ICE, but int maybe_vla(int n) { goto label; int arr[__builtin_expect(({0;}), 0)]; label: return sizeof(arr); } ... is accepted. This seems like a bug in both compilers to me: __builtin_expect isn't supposed to affect the interpretation of its first operand, and presumably shouldn't be weakening the strict ICE checks. So I think the original testcase is probably invalid. Nonetheless, there is a bug here in how we evaluate ICEs involving statement expressions. For example, given: #define fold(x) (__builtin_constant_p(x) ? (x) : (x)) int f() { goto label; int arr[fold(({42;}))]; label: return sizeof(arr); } we incorrectly constant-evaluate the bound of 'arr' to 0.
Fixed in bdf6fbc939646b52af61c0bae7335623a8be59f4. @tstellar, feel free to cherry-pick to the 12.0 release after this has had a couple of days in tree. The fix should be pretty safe, and fixes a wrong-code bug. However, it's not a recent regression, and the situation that triggers the bug is very obscure, so I think it would also be OK to defer this fix to the Clang 13 release.
I can open a separate bug if necessary but bdf6fbc939646b52af61c0bae7335623a8be59f4 causes a crash while compiling mm/gup.c in the Linux kernel on the 5.4 branch. creduce spits out: $ cat gup.i int a; void b() { a = ({ while (1) ; 0; }); } $ clang -fsyntax-only -x c gup.i clang: /home/nathan/cbl/github/tc-build/llvm-project/clang/lib/AST/ExprConstant.cpp:12486: (anonymous namespace)::DelayedNoteFailureRAII::~DelayedNoteFailureRAII(): Assertion `ContinueAfterFailure && "Shouldn't have kept evaluating on failure."' 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: clang -fsyntax-only -x c gup.i 1. gup.i:8:1: current parser token '}' 2. gup.i:2:10: parsing function body 'b' 3. gup.i:2:10: in compound statement ('{}') #0 0x0000000002a62693 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x2a62693) #1 0x0000000002a6052e llvm::sys::RunSignalHandlers() (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x2a6052e) #2 0x0000000002a61a2d llvm::sys::CleanupOnSignal(unsigned long) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x2a61a2d) #3 0x00000000029eeee3 (anonymous namespace)::CrashRecoveryContextImpl::HandleCrash(int, unsigned long) CrashRecoveryContext.cpp:0:0 #4 0x00000000029ef01e CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0 #5 0x00007f653833b730 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12730) #6 0x00007f6537c4f7bb raise (/lib/x86_64-linux-gnu/libc.so.6+0x377bb) #7 0x00007f6537c3a535 abort (/lib/x86_64-linux-gnu/libc.so.6+0x22535) #8 0x00007f6537c3a40f (/lib/x86_64-linux-gnu/libc.so.6+0x2240f) #9 0x00007f6537c48102 (/lib/x86_64-linux-gnu/libc.so.6+0x30102) #10 0x00000000047faaf7 (anonymous namespace)::IntExprEvaluator::VisitBinaryOperator(clang::BinaryOperator const*) ExprConstant.cpp:0:0 #11 0x00000000047c74b1 Evaluate(clang::APValue&, (anonymous namespace)::EvalInfo&, clang::Expr const*) ExprConstant.cpp:0:0 #12 0x00000000047c46b1 EvaluateAsRValue((anonymous namespace)::EvalInfo&, clang::Expr const*, clang::APValue&) ExprConstant.cpp:0:0 #13 0x00000000047c4a6c clang::Expr::EvaluateForOverflow(clang::ASTContext const&) const (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x47c4a6c) #14 0x0000000003e37edc clang::Sema::CheckForIntOverflow(clang::Expr*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3e37edc) #15 0x0000000003e38439 clang::Sema::CheckCompletedExpr(clang::Expr*, clang::SourceLocation, bool) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3e38439) #16 0x00000000041af7cd clang::Sema::ActOnFinishFullExpr(clang::Expr*, clang::SourceLocation, bool, bool) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x41af7cd) #17 0x000000000438d441 clang::Sema::ActOnExprStmt(clang::ActionResult<clang::Expr*, true>, bool) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x438d441) #18 0x0000000003d36eeb clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::Parser::ParsedAttributesWithRange&) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3d36eeb) #19 0x0000000003d35303 clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3d35303) #20 0x0000000003d3e3d1 clang::Parser::ParseCompoundStatementBody(bool) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3d3e3d1) #21 0x0000000003d3f1a0 clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3d3f1a0) #22 0x0000000003cb9182 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3cb9182) #23 0x0000000003cea939 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3cea939) #24 0x0000000003cb82cc clang::Parser::ParseDeclOrFunctionDefInternal(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3cb82cc) #25 0x0000000003cb7d25 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3cb7d25) #26 0x0000000003cb696a clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3cb696a) #27 0x0000000003cb4f20 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, bool) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3cb4f20) #28 0x0000000003caf40d clang::ParseAST(clang::Sema&, bool, bool) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3caf40d) #29 0x00000000034c2030 clang::FrontendAction::Execute() (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x34c2030) #30 0x00000000033f737a clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x33f737a) #31 0x0000000003563af8 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x3563af8) #32 0x00000000017d73e4 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x17d73e4) #33 0x00000000017d4e62 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) driver.cpp:0:0 #34 0x00000000032a2fd2 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const::$_1>(long) Job.cpp:0:0 #35 0x00000000029eedf7 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x29eedf7) #36 0x00000000032a2b47 clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x32a2b47) #37 0x000000000326f031 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&) const (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x326f031) #38 0x000000000326f327 clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) const (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x326f327) #39 0x000000000328456e clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x328456e) #40 0x00000000017d46e6 main (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x17d46e6) #41 0x00007f6537c3c09b __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409b) #42 0x00000000017d1b4a _start (/home/nathan/cbl/github/tc-build/build/llvm/stage1/bin/clang-13+0x17d1b4a) clang-13: error: clang frontend command failed with exit code 134 (use -v to see invocation) ClangBuiltLinux clang version 13.0.0 (https://github.com/llvm/llvm-project fa211f3ce9a9c83b72a524799e4e060e79e92da4) Target: x86_64-unknown-linux-gnu Thread model: posix InstalledDir: /home/nathan/cbl/github/tc-build/build/llvm/stage1/bin clang-13: note: diagnostic msg: ******************** PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT: Preprocessed source(s) and associated run script(s) are located at: clang-13: note: diagnostic msg: /tmp/gup-601c49.c clang-13: note: diagnostic msg: /tmp/gup-601c49.sh clang-13: note: diagnostic msg: ********************
(In reply to Nathan Chancellor from comment #5) > I can open a separate bug if necessary but > bdf6fbc939646b52af61c0bae7335623a8be59f4 causes a crash while compiling > mm/gup.c in the Linux kernel on the 5.4 branch. > Given that this patch caused a regression, I won't merge it into release/12.x, until we can find a fix for the regression.
This bug was not resolved in time for the 12.0.0 release, so it will have to wait for 12.0.1. If you feel this is a high-priority bug that should be fixed for 12.0.0, please re-add release-12.0.0 to the Blocks field and add a comment explaining why this is high-priority.