clang --target compiler arg overridden when attempting to find system defaults

[schultetwin1]

Type: LanguageService

Describe the bug

• OS and Version: Windows 10 19631
• VS Code Version: 1.45.1

When using the clang compiler, the logic in cpptools.exe to find compiler default defines and include paths finds the wrong information if the compiler arg --target=<some target> is present.

I believe this is because cpptools is overridding the --target argument. I notice that when I pass in the compiler argument --target=aarch64-none-linux-android29, the resulting process to detect system include paths and defines has both --target=aarch64-none-linux-android29 and --target=aarch64-arm-none-eabi. This means the detected defines and include paths will not be Android specific but a generic aarch64 set of includes/defines instead.

Expected behavior
I would expect cpptools to not override the --target argument when that is past in as a compiler arg.

[Colengms]

There are likely other args that would cause similar issues. i.e. -march, -mcpu

[sean-mcmanus]

Your fix should be available in https://github.com/microsoft/vscode-cpptools/releases/tag/0.29.0-insiders now.

[schultetwin1]

Looks like its working! Feel free to close this out if you'd like.

[michelleangela]

Thanks for verifying. We'll close the issue when 0.29.0 is out of insiders and is released.