Segmentation fault in clang::CodeGen::CodeGenFunction::EmitScalarExpr

[jtsylve]

Bugzilla Link	45311
Version	8.0
OS	Linux
CC	@zygoloid

Extended Description

As you can see here I'm testing my codebase against several versions of clang++ running on Linux: https://travis-ci.org/github/jtsylve/yatlib/builds/667081643

Clang 5 and 6 fail to compile for unrelated reasons which I can mitigate. Clang 8, 9, 10, and 11 all crash with a similar Segmentation fault. The code that triggers the crash can be found by checking out commit ef0cc1852c353cef024ea5cea0ea371e7259fde5 from https://github.com/jtsylve/yatlib

Clang 8 stacktrace below:

Stack dump:
0. Program arguments: /usr/lib/llvm-8/bin/clang -cc1 -triple x86_64-pc-linux-gnu -emit-obj -disable-free -disable-llvm-verifier -discard-value-names -main-file-name format_test.cpp -mrelocation-model static -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debug-info-kind=limited -dwarf-version=4 -debugger-tuning=gdb -momit-leaf-frame-pointer -coverage-notes-file /home/travis/build/jtsylve/yatlib/tests/CMakeFiles/unittests.dir/format_test.cpp.gcno -resource-dir /usr/lib/llvm-8/lib/clang/8.0.1 -I /home/travis/build/jtsylve/yatlib/thirdparty/catch2/single_include -I /home/travis/build/jtsylve/yatlib/include -D NDEBUG -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0 -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/x86_64-linux-gnu/c++/7.5.0 -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/x86_64-linux-gnu/c++/7.5.0 -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0/backward -internal-isystem /usr/include/clang/8.0.1/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.1/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wall -Wextra -Wshadow -Wnon-virtual-dtor -Wold-style-cast -Wcast-align -Wunused -Woverloaded-virtual -Wpedantic -Wconversion -Wsign-conversion -Wnull-dereference -Wdouble-promotion -Wformat=2 -std=gnu++17 -fdeprecated-macro -fdebug-compilation-dir /home/travis/build/jtsylve/yatlib/tests -ferror-limit 19 -fmessage-length 80 -fobjc-runtime=gcc -fcxx-exceptions -fexceptions -fdiagnostics-show-option -fcolor-diagnostics -vectorize-loops -vectorize-slp -o CMakeFiles/unittests.dir/format_test.cpp.o -x c++ /home/travis/build/jtsylve/yatlib/tests/format_test.cpp -faddrsig

1. parser at end of file
2. Per-file LLVM IR generation
3. /home/travis/build/jtsylve/yatlib/tests/format_test.cpp:72:1 <Spelling=:185:1>: Generating code for declaration '____C_A_T_C_H____T_E_S_T____4'
4. /home/travis/build/jtsylve/yatlib/tests/format_test.cpp:86:3 <Spelling=/home/travis/build/jtsylve/yatlib/thirdparty/catch2/single_include/catch2/catch.hpp:2676:8>: LLVM IR generation of compound statement ('{}')
   #​0 0x00007fc6412cd59f llvm::sys::PrintStackTrace(llvm::raw_ostream&) (/usr/lib/x86_64-linux-gnu/libLLVM-8.so.1+0x97159f)
   #​1 0x00007fc6412cb9f0 llvm::sys::RunSignalHandlers() (/usr/lib/x86_64-linux-gnu/libLLVM-8.so.1+0x96f9f0)
   #​2 0x00007fc6412cd9a8 (/usr/lib/x86_64-linux-gnu/libLLVM-8.so.1+0x9719a8)
   #​3 0x00007fc6445b4890 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12890)
   #​4 0x00000000008e4ed9 (/usr/lib/llvm-8/bin/clang+0x8e4ed9)
   #​5 0x00000000008d6a8f clang::CodeGen::CodeGenFunction::EmitScalarExpr(clang::Expr const*, bool) (/usr/lib/llvm-8/bin/clang+0x8d6a8f)
   #​6 0x00000000008a4b06 clang::CodeGen::CodeGenFunction::EmitAnyExpr(clang::Expr const*, clang::CodeGen::AggValueSlot, bool) (/usr/lib/llvm-8/bin/clang+0x8a4b06)
   #​7 0x00000000008a4a59 clang::CodeGen::CodeGenFunction::EmitIgnoredExpr(clang::Expr const*) (/usr/lib/llvm-8/bin/clang+0x8a4a59)
   #​8 0x00000000008e7cc8 (/usr/lib/llvm-8/bin/clang+0x8e7cc8)
   #​9 0x00000000008e0c1b (/usr/lib/llvm-8/bin/clang+0x8e0c1b)
   #​10 0x00000000008d6a8f clang::CodeGen::CodeGenFunction::EmitScalarExpr(clang::Expr const*, bool) (/usr/lib/llvm-8/bin/clang+0x8d6a8f)
   #​11 0x00000000008a4b06 clang::CodeGen::CodeGenFunction::EmitAnyExpr(clang::Expr const*, clang::CodeGen::AggValueSlot, bool) (/usr/lib/llvm-8/bin/clang+0x8a4b06)
   #​12 0x00000000008a4a59 clang::CodeGen::CodeGenFunction::EmitIgnoredExpr(clang::Expr const*) (/usr/lib/llvm-8/bin/clang+0x8a4a59)
   #​13 0x0000000000712b92 clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) (/usr/lib/llvm-8/bin/clang+0x712b92)
   #​14 0x000000000071ba70 clang::CodeGen::CodeGenFunction::EmitCompoundStmtWithoutScope(clang::CompoundStmt const&, bool, clang::CodeGen::AggValueSlot) (/usr/lib/llvm-8/bin/clang+0x71ba70)
   #​15 0x000000000071b048 clang::CodeGen::CodeGenFunction::EmitCompoundStmt(clang::CompoundStmt const&, bool, clang::CodeGen::AggValueSlot) (/usr/lib/llvm-8/bin/clang+0x71b048)
   #​16 0x00000000007131df clang::CodeGen::CodeGenFunction::EmitSimpleStmt(clang::Stmt const*) (/usr/lib/llvm-8/bin/clang+0x7131df)
   #​17 0x0000000000712abb clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) (/usr/lib/llvm-8/bin/clang+0x712abb)
   #​18 0x00000000007146ae clang::CodeGen::CodeGenFunction::EmitDoStmt(clang::DoStmt const&, llvm::ArrayRef<clang::Attr const*>) (/usr/lib/llvm-8/bin/clang+0x7146ae)
   #​19 0x0000000000713056 clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) (/usr/lib/llvm-8/bin/clang+0x713056)
   #​20 0x000000000071ba70 clang::CodeGen::CodeGenFunction::EmitCompoundStmtWithoutScope(clang::CompoundStmt const&, bool, clang::CodeGen::AggValueSlot) (/usr/lib/llvm-8/bin/clang+0x71ba70)
   #​21 0x000000000075545e clang::CodeGen::CodeGenFunction::EmitFunctionBody(clang::Stmt const*) (/usr/lib/llvm-8/bin/clang+0x75545e)
   #​22 0x0000000000755cdf clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) (/usr/lib/llvm-8/bin/clang+0x755cdf)
   #​23 0x000000000076c512 clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/usr/lib/llvm-8/bin/clang+0x76c512)
   #​24 0x0000000000766d0b clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/usr/lib/llvm-8/bin/clang+0x766d0b)
   #​25 0x000000000075ed8e clang::CodeGen::CodeGenModule::EmitDeferred() (/usr/lib/llvm-8/bin/clang+0x75ed8e)
   #​26 0x000000000075e267 clang::CodeGen::CodeGenModule::Release() (/usr/lib/llvm-8/bin/clang+0x75e267)
   #​27 0x0000000000d58944 (/usr/lib/llvm-8/bin/clang+0xd58944)
   #​28 0x0000000000d56438 (/usr/lib/llvm-8/bin/clang+0xd56438)
   #​29 0x00000000011dcbb3 clang::ParseAST(clang::Sema&, bool, bool) (/usr/lib/llvm-8/bin/clang+0x11dcbb3)
   #​30 0x0000000000add2bf clang::FrontendAction::Execute() (/usr/lib/llvm-8/bin/clang+0xadd2bf)
   #​31 0x0000000000a9bde8 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/usr/lib/llvm-8/bin/clang+0xa9bde8)
   #​32 0x0000000000b62d96 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/usr/lib/llvm-8/bin/clang+0xb62d96)
   #​33 0x00000000006a2dec cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/usr/lib/llvm-8/bin/clang+0x6a2dec)
   #​34 0x00000000006a1336 main (/usr/lib/llvm-8/bin/clang+0x6a1336)
   #​35 0x00007fc63fc4db97 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b97)
   #​36 0x000000000069ea5a _start (/usr/lib/llvm-8/bin/clang+0x69ea5a)
   clang: error: unable to execute command: Segmentation fault (core dumped)

[jtsylve]

This commit seems to mitigate the crash, so I suspect the root cause has something to do with the friend function being defined inline to the class.

jtsylve/yatlib@2a0a091

[llvmbot]

Mind attaching the preprocessed source, as well as the relevant cc1 line from -v -save-temps? That will make it easer to repro this.

[nunoplopes]

This has been fixed by the commit mentioned above.