C++ debugger crashes on M2 Mac when using SDL and std::map

Type: Bug

While working on a project using SDL, I ran into a weird issue where after setting a breakpoint, the VS Code debugger (using lldb) would stop at the breakpoint and show the stack trace, but couldn't load variables or step. The program then also froze, even after stopping the debugger and had to be force quit. I reduced it to the following minimal example:

main.cpp

#include <SDL.h>
#include <map>

int main() {
    if (SDL_Init(SDL_INIT_VIDEO) != 0)
    {
        return -1;
    }

    std::map<int, int> badMap;

    return 0;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.15)
project(LLDB Repro)

# Set the C++ standard to be used for compilation
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

# Define the source files to be compiled
file(GLOB_RECURSE SOURCE_FILES 
    main.cpp
)

# Create an executable from the source files
add_executable(${PROJECT_NAME} ${SOURCE_FILES})

# Find the SDL2 package
find_package(SDL2 REQUIRED)

# Add the SDL2 include directories and link the SDL2 libraries
target_include_directories(${PROJECT_NAME} PRIVATE ${SDL2_INCLUDE_DIRS})
target_link_libraries(${PROJECT_NAME} ${SDL2_LIBRARIES})

launch.json

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "(lldb) Launch",
            "type": "cppdbg",
            "request": "launch",
            "program": "${command:cmake.launchTargetPath}",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "lldb"
        }
    ],
}

c_cpp_properties.json

{
    "configurations": [
        {
            "name": "Mac",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "defines": [],
            "macFrameworkPath": [
                "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
            ],
            "compilerPath": "/usr/bin/clang",
            "cStandard": "c17",
            "cppStandard": "c++20",
            "intelliSenseMode": "macos-clang-arm64",
            "configurationProvider": "ms-vscode.cmake-tools"
        }
    ],
    "version": 4
}

If I set a breakpoint in the main function, VS Code will break there, but then something crashes internally. If you remove either the map or SDL_Init, the problem disappears. I also tried debugging manually from the command line with LLDB, but there the issue doesn't appear.

robert@RMBA LLDB Repro % lldb --version
lldb-1403.0.17.64
Apple Swift version 5.8 (swiftlang-5.8.0.124.2 clang-1403.0.22.11.100)
robert@RMBA LLDB Repro % brew list --versions sdl2
sdl2 2.26.5

Extension version: 1.15.4
VS Code version: Code 1.78.2 (Universal) (b3e4e68a0bc097f0ae7907b217c1119af9e03435, 2023-05-10T14:44:45.204Z)
OS version: Darwin arm64 22.4.0
Modes:
Sandboxed: Yes

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pythonms35:30701012
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Riprodurre il crash sulla configurazione M2 segnalata usando main.cpp, CMakeLists.txt, launch.json e c_cpp_properties.json, quindi confrontare il comportamento di VS Code cppdbg con LLDB dalla riga di comando. Iniziare tracciando il percorso di avvio di LLDB e il percorso delle variabili e dell’esecuzione passo-passo dell’estensione; il lavoro è completato quando l’esempio minimo con SDL e std::map non si blocca né va più in crash e le variabili possono essere ispezionate e percorse passo-passo.