[Clang][Windows] Runtime crash!,when ASAN is enabled

[jiangxinhaha]

Clang Version: 20.1.6
Crash stack ：

[AaronBallman]

Thank you for the report! Can you provide source code so we can reproduce the issue ourselves? Bonus points if you can reproduce it on something like Compiler Explorer

[jiangxinhaha]

Thank you for the report! Can you provide source code so we can reproduce the issue ourselves? Bonus points if you can reproduce it on something like Compiler Explorer

There is nothing special about the code. I just used VS2022 to create a basic desktop GUI application. Then the VS toolset was configured with clang 20.1.6.
1，I enabled Asan by configuring /fsanitize=address （/MD）；
2，Link properties configured with the same version of clang_rt.asan_dynamic-x86_64.dll；
Finally, a runtime crash occurred when the app was started。

[GkvJwa]

Cannot be run with debugger attached
it will crash at memset

You can run the program directly without attaching a debugger

[jiangxinhaha]

Cannot be run with debugger attached it will crash at memset

You can run the program directly without attaching a debugger

@GkvJwa
There are two problems here:

1. Debugging applications is a common operation. How can we support Asan during debugging? MSVC Asan supports this;
2. We can only judge whether the release version does not enable Asan, otherwise it will be enabled. But we cannot judge whether the debugger has enabled and disabled Asan (as shown in the above conclusion, in this scenario it will crash at memset).

[jiangxinhaha]

Cannot be run with debugger attached it will crash at memset
You can run the program directly without attaching a debugger

@GkvJwa There are two problems here:

1. Debugging applications is a common operation. How can we support Asan during debugging? MSVC Asan supports this;
2. We can only judge whether the release version does not enable Asan, otherwise it will be enabled. But we cannot judge whether the debugger has enabled and disabled Asan (as shown in the above conclusion, in this scenario it will crash at memset).

How to use the debugger to debug the application without crashing after turning on ASAN？