templight++ aborts with an error

[calum74]

On the latest main of llvm, the generated C++ compiler (templight++) aborts with an error:

-- Check for working CXX compiler: /Users/calum/projects/llvm-project/build/bin/templight++ - broken
CMake Error at /opt/homebrew/Cellar/cmake/3.20.1/share/cmake/Modules/CMakeTestCXXCompiler.cmake:59 (message):
  The C++ compiler

    "/Users/calum/projects/llvm-project/build/bin/templight++"

  is not able to compile a simple test program.

  It fails with the following output:

    Change Dir: /Users/calum/projects/fei-parser/build-templight/CMakeFiles/CMakeTmp
    
    Run Build Command(s):/usr/bin/make -f Makefile cmTC_cf156/fast && /Applications/Xcode.app/Contents/Developer/usr/bin/make  -f CMakeFiles/cmTC_cf156.dir/build.make CMakeFiles/cmTC_cf156.dir/build
    Building CXX object CMakeFiles/cmTC_cf156.dir/testCXXCompiler.cxx.o
    /Users/calum/projects/llvm-project/build/bin/templight++   -arch arm64 -o CMakeFiles/cmTC_cf156.dir/testCXXCompiler.cxx.o -c /Users/calum/projects/fei-parser/build-templight/CMakeFiles/CMakeTmp/testCXXCompiler.cxx
    Assertion failed: (isSafeToReferenceAfterResize(Elt, NewSize) && "Attempting to reference an element of the vector in an operation " "that invalidates it"), function assertSafeToReferenceAfterResize, file /Users/calum/projects/llvm-project/llvm/include/llvm/ADT/SmallVector.h, line 177.
    Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
    0  templight++              0x0000000103ff741c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 56
    1  templight++              0x0000000103ff640c llvm::sys::RunSignalHandlers() + 72
    2  templight++              0x0000000103ff7a88 SignalHandler(int) + 304
    3  libsystem_platform.dylib 0x000000019ded2c44 _sigtramp + 56
    4  libsystem_pthread.dylib  0x000000019de8743c pthread_kill + 292
    5  libsystem_c.dylib        0x000000019ddcf454 abort + 124
    6  libsystem_c.dylib        0x000000019ddce8d4 err + 0
    7  templight++              0x000000010617e72c main.cold.32 + 0
    8  templight++              0x0000000102276324 main + 9540
    9  libdyld.dylib            0x000000019dea5430 start + 4
    PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
    Stack dump:
    0.  Program arguments: /Users/calum/projects/llvm-project/build/bin/templight++ -arch arm64 -o CMakeFiles/cmTC_cf156.dir/testCXXCompiler.cxx.o -c /Users/calum/projects/fei-parser/build-templight/CMakeFiles/CMakeTmp/testCXXCompiler.cxx
    make[2]: *** [CMakeFiles/cmTC_cf156.dir/testCXXCompiler.cxx.o] Abort trap: 6
    make[1]: *** [cmTC_cf156/fast] Error 2    

A few minor and probably insignificant details, are that (a) I needed to patch the source code a bit to make it compile, (b) I'm running on Apple Silicon (arm64_osx) and (c) I'm using a release build of clang (-DCMAKE_BUILD_TYPE=Release) because I needed the performance.

Steps to reproduce

1. Follow the installation instructions,

• Clone clang
• Clone template++ into the tools folder
• Update the CMakeLists.txt
• Additional step: Patch up the templight source code so that it builds again
• Additional step (which may not be relevant): Configure cmake with -DCMAKE_BUILD_TYPE=Release
• Build clang with templight++

2. Configure the target project, in CMake, with CMAKE_CXX_COMPILER:STRING=/Users/calum/projects/llvm-project/build/bin/templight++
3. Build the target project, using make.

Causes

I'm not very familiar with llvm and templight yet, so here are some guesses

• My patching of the source code was incorrect
• Templight doesn't work on the latest llvm
• Something has gone wrong on Apple Silicon (arm64)

Any pointers would be appreciated!

[Twon]

I also experienced this issue, but this only appears to happen with the debug build (which is what CMake will build by default). Trying adding -D CMAKE_BUILD_TYPE=Release when invoking CMake to ensure you build the release configuration. With the assets removed in the release build then the program will run.