clang-tidy crash with empty `directory` in compilation database

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LLVM_SYMBOLIZER_PATH=llvm-symbolizer-15 clang-tidy-15 -checks= -p=/tmp/crash /tmp/crash/test.cpp

LLVM ERROR: Cannot chdir into ""!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.      Program arguments: clang-tidy-15 -checks= -p=/tmp/crash /tmp/crash/test.cpp
 #0 0x00007f1ece971721 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/lib/llvm-15/bin/../lib/libLLVM-15.so.1+0xf01721)
 #1 0x00007f1ece96f45e llvm::sys::RunSignalHandlers() (/usr/lib/llvm-15/bin/../lib/libLLVM-15.so.1+0xeff45e)
 #2 0x00007f1ece971c4b (/usr/lib/llvm-15/bin/../lib/libLLVM-15.so.1+0xf01c4b)
 #3 0x00007f1ed849a420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14420)
 #4 0x00007f1ecd55300b raise /build/glibc-SzIz7B/glibc-2.31/signal/../sysdeps/unix/sysv/linux/raise.c:51:1
 #5 0x00007f1ecd532859 abort /build/glibc-SzIz7B/glibc-2.31/stdlib/abort.c:81:7
 #6 0x00007f1ece8a7152 llvm::report_fatal_error(llvm::Twine const&, bool) (/usr/lib/llvm-15/bin/../lib/libLLVM-15.so.1+0xe37152)
 #7 0x00007f1ed72db219 clang::tooling::ClangTool::run(clang::tooling::ToolAction*) (/usr/lib/llvm-15/bin/../lib/libclang-cpp.so.15+0x28db219)
 #8 0x00007f1ed97e0d2f clang::tidy::runClangTidy(clang::tidy::ClangTidyContext&, clang::tooling::CompilationDatabase const&, llvm::ArrayRef<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>>, llvm::IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem>, bool, bool, llvm::StringRef) (/usr/lib/llvm-15/bin/clang-tidy+0x12edd2f)
 #9 0x00007f1ed8c74592 clang::tidy::clangTidyMain(int, char const**) (/usr/lib/llvm-15/bin/clang-tidy+0x781592)
#10 0x00007f1ecd534083 __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:342:3
#11 0x00007f1ed8c6f3de _start (/usr/lib/llvm-15/bin/clang-tidy+0x77c3de)
Aborted (core dumped)

crash.zip

Ubuntu clang version 15.0.0-++20220818073040+0334c1ac1b02-1~exp1~20220818073137.27

[firewave]

This also happens with trunk:

LLVM_SYMBOLIZER_PATH=llvm-symbolizer-16 clang-tidy-16 -checks= -p=/tmp/crash /tmp/crash/test.cpp

LLVM ERROR: Cannot chdir into ""!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.      Program arguments: clang-tidy-16 -checks= -p=/tmp/crash /tmp/crash/test.cpp
 #0 0x00007f9acbd6f7f1 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/lib/llvm-16/bin/../lib/libLLVM-16.so.1+0xeff7f1)
 #1 0x00007f9acbd6d910 llvm::sys::RunSignalHandlers() (/usr/lib/llvm-16/bin/../lib/libLLVM-16.so.1+0xefd910)
 #2 0x00007f9acbd6fce2 (/usr/lib/llvm-16/bin/../lib/libLLVM-16.so.1+0xeffce2)
 #3 0x00007f9ad547a420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14420)
 #4 0x00007f9aca94300b raise /build/glibc-SzIz7B/glibc-2.31/signal/../sysdeps/unix/sysv/linux/raise.c:51:1
 #5 0x00007f9aca922859 abort /build/glibc-SzIz7B/glibc-2.31/stdlib/abort.c:81:7
 #6 0x00007f9acbcaffd8 llvm::report_fatal_error(llvm::Twine const&, bool) (/usr/lib/llvm-16/bin/../lib/libLLVM-16.so.1+0xe3ffd8)
 #7 0x00007f9ad4300c37 clang::tooling::ClangTool::run(clang::tooling::ToolAction*) (/usr/lib/llvm-16/bin/../lib/libclang-cpp.so.16+0x27a0c37)
 #8 0x00007f9ad6837d4f clang::tidy::runClangTidy(clang::tidy::ClangTidyContext&, clang::tooling::CompilationDatabase const&, llvm::ArrayRef<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>>, llvm::IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem>, bool, bool, llvm::StringRef) (/usr/lib/llvm-16/bin/clang-tidy+0x1362d4f)
 #9 0x00007f9ad5c8037b clang::tidy::clangTidyMain(int, char const**) (/usr/lib/llvm-16/bin/clang-tidy+0x7ab37b)
#10 0x00007f9aca924083 __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:342:3
#11 0x00007f9ad5c7b3fe _start (/usr/lib/llvm-16/bin/clang-tidy+0x7a63fe)
Aborted (core dumped)

Ubuntu clang version 16.0.0-++20220819052909+5517401f936a-1~exp1~20220819173009.351

[llvmbot]

@llvm/issue-subscribers-clang-tidy

[PiotrZSL]

This fails with:

584         llvm::report_fatal_error("Cannot chdir into \"" +
585                                  Twine(CompileCommand.Directory) + "\"!");

I don't think that directory is an optional field: https://clang.llvm.org/docs/JSONCompilationDatabase.html
Probably best would be simply not change directory if it's unknown.

[firewave]

I don't think that directory is an optional field: https://clang.llvm.org/docs/JSONCompilationDatabase.html
Probably best would be simply not change directory if it's unknown.

I don't think so either but it produces an error which encourages you to report it upstream. I mainly filed this as it is treated like a crash/assert instead of "simply" reporting it as an error. I think that should be changed. I forgot to express that in my report.