Unable to catch exceptions with clang++ 18.1.5 on macos ARM (try-catch does nothing)

[themightyoarfish]

System Info

• OS: macos 12.6.5
• arch: Apple silicon

Compiler info

• Homebrew clang version 18.1.5
• Target: arm64-apple-darwin21.6.0
• Thread model: posix
• InstalledDir: /opt/homebrew/Cellar/llvm/18.1.5/bin

Problem description

When an exception of custom type is thrown in the constructor for a class, and that constuctor gets invoked in the return statement of a function, this exception cannot be caught in the calling code.

So far the exact circumstances under which this happens or does not happen are unknown to me, but I have attached a small CMake project to demonstrate.

The problem does not occur with std::runtime_error, only with a subclass.

How to run

• export CC=/opt/homebrew/Cellar/llvm/18.1.5/bin/clang CXX=/opt/homebrew/Cellar/llvm/18.1.5/bin/clang++
• cmake ..
• make && ./test

Result

ld: warning: dylib (/opt/homebrew/opt/llvm/lib/c++/libc++.dylib) was built for newer macOS version (12.7) than being linked (12.6)
[100%] Built target test
Throwing
libc++abi: terminating due to uncaught exception of type Error: hallo
Abort trap: 6

Minimal reproducible project

Here is a minimal cmake project (with build artifacts on my machine, in case that is relevant)

clang-wtf.zip

[llvmbot]

@llvm/issue-subscribers-clang-codegen

Author: Rasmus (themightyoarfish)

# System Info

• OS: macos 12.6.5
• arch: Apple silicon

Compiler info

• Homebrew clang version 18.1.5
• Target: arm64-apple-darwin21.6.0
• Thread model: posix
• InstalledDir: /opt/homebrew/Cellar/llvm/18.1.5/bin

Problem description

When an exception of custom type is thrown in the constructor for a class, and that constuctor gets invoked in the return statement of a function, this exception cannot be caught in the calling code.

So far the exact circumstances under which this happens or does not happen are unknown to me, but I have attached a small CMake project to demonstrate.

The problem does not occur with std::runtime_error, only with a subclass.

How to run

• export CC=/opt/homebrew/Cellar/llvm/18.1.5/bin/clang CXX=/opt/homebrew/Cellar/llvm/18.1.5/bin/clang++
• cmake ..
• make && ./test

Result

ld: warning: dylib (/opt/homebrew/opt/llvm/lib/c++/libc++.dylib) was built for newer macOS version (12.7) than being linked (12.6)
[100%] Built target test
Throwing
libc++abi: terminating due to uncaught exception of type Error: hallo
Abort trap: 6

Minimal reproducible project

Here is a minimal cmake project (with build artifacts on my machine, in case that is relevant)

clang-wtf.zip