[clang] [Clang][Driver][Test] Created test for unsupported driver options (PR #120900)

[Mészáros Gergely via cfe-commits]

Maetveis wrote:

Sorry I was caught up with work, and didn't find the time to look at this until now.

> @Maetveis Do you have any thoughts on the following two groups of options that are unexpectedly succeeding? I'll note that I did come across some options for which the driver appears to correct user error by adding the appropriate driver option, like testing "`-fexperimental-sanitize-metadata=atomics`" with the default driver and the driver adding `-cc1`

For `-fexperimental-sanitize-metadata=atomics` I think it should be hidden by `-fexperimental-sanitize-metadata=<anything>` (Which is driver only). Maybe your search logic for hidden options has bugs, but I didn't dive into it to check.


> 1. "`fheinous-gnu-extensions`" & "`fcuda-approx-transcendentals`" with `-cc1`
>    Both of these unexpectedly succeed with `clang -cc1`. Notably, they both have aliases that are supported for `-cc1`, ([ex: fheinous-gnu-extensions](https://github.com/llvm/llvm-project/blob/75781fa3c77f14640459a97d4265dda76d80e453/clang/include/clang/Driver/Options.td#L2823)), but those aliases expectedly fail when used with `-cc1`, which suggests aliases aren't the issue.
> 
> Ex: `clang -cc1 -fheinous-gnu-extensions -x c++ - < /dev/null 2>&1`
> 
> 2. "`mno-strict-align`" & "`mstrict-align`" with `-cc1`
>    Both of these unexpectedly succeed with `clang -cc1`. Both of these have no alias. They're part of the m_Group and the CompileOnly_Group, which don't include `-cc1` for visibility.
> 
> Ex: `clang -cc1 -mno-strict-align -x c++ - < /dev/null 2>&1`

These all produce errors for me. Are you sure you're testing everything right? You have an up-to-date clang build for example? The testing tool should give you an output like `llvm-lit: (...)/llvm/utils/lit/lit/llvm/config.py:506: note: using clang (...)/build/bin/clang` that should be pointing into the llvm build folder.




https://github.com/llvm/llvm-project/pull/120900