C++: wrong exception handling with std::stoi on non-debug builds

[sagehane]

Zig Version

0.10.0-dev.717+90f2a8d9c

Steps to Reproduce

Reproduced on NixOS Unstable and Arch Linux.

---

Run the following code with any build mode but debug mode.

Sample stoi.cpp:

#include <iostream>

int main() {
  try {
    // Can be stoi, stoul, stoull, etc.
    std::stoi("test", nullptr, 0);
  } catch (...) {
  }

  // Commenting out this line fixes the runtime error.
  // Only causes an error on Fast/Small if it's equal to the function above.
  std::stoi("0");

  return 0;
}

Sample stoi_safe.cpp:

#include <iostream>

int main() {
  try {
    // Can be stoi, stoul, stoull, etc.
    std::stoi("test", nullptr, 0);
  } catch (...) {
  }

  // Commenting out this line fixes the runtime error.
  // Only causes an error on Fast/Small if it's equal to the function above.
  std::stoll("0");

  return 0;
}

Expected Behavior

The code should run (and essentially do nothing) successfully.

$ zig run -lc++ -O Debug stoi_safe.cpp

$ zig run -lc++ -O Debug stoi.cpp

My attempt at replicating the flags passed to Clang by looking at the outputs of --verbose-cc of -O ReleaseSmall:

$ clang++ -fno-spell-checking -flto -mred-zone -fomit-frame-pointer -DNDEBUG -Os -fno-stack-protector -fPIC -fno-unwind-tables -MD -MV -fPIC -fstrict-aliasing -funwind-tables -std=c++11 stoi.cpp
$ ./a.out

Actual Behavior

Causes a runtime error.

Safe:

$ zig run -lc++ -O ReleaseSafe stoi_safe.cpp
libc++abi: terminating with uncaught exception of type std::invalid_argument: stoi: no conversion
Aborted (core dumped)

$ zig run -lc++ -O ReleaseSafe stoi.cpp
libc++abi: terminating with uncaught exception of type std::invalid_argument: stoi: no conversion
Aborted (core dumped)

Fast/Small:

$ zig run -lc++ -O ReleaseSmall stoi_safe.cpp

$ zig run -lc++ -O ReleaseSmall stoi.cpp
libc++abi: terminating with uncaught exception of type std::invalid_argument: stoi: no conversion
Aborted (core dumped)

[sagehane]

Update. I tried running the same code with 0.10.0-dev.2836+2360f8c49 and it seems to throw that uncaught exception error on safe mode even after commenting out the 2nd call to stoi. The behavior doesn't seem to have changed for other release modes.

I also noticed that #9591 might be relevant.

[sagehane]

@andrewrk, I don't seem to be able to reproduce this issue anymore. Do you reckon this is safe to close?

[andrewrk]

I think we should try to add test coverage for it before closing if we can.