[PATCH] D53457: clang-cl: Add "/clang:" pass-through arg support.

[Hans Wennborg via Phabricator via cfe-commits]

hans added a comment.

In https://reviews.llvm.org/D53457#1279191, @neerajksingh wrote:

> In https://reviews.llvm.org/D53457#1278579, @hans wrote:
>
> > The `-Xclang` option has the same issue, and I think `/clang:` should work similarly, i.e. `/clang:-MF /clang:<filename>`. It's not pretty, but at least it's consistent. Yes, that means processing consecutive `/Xclang:` options together, but hopefully that's doable.
>
>
> It looks like the handling for -Xclang is a lot simpler (in `Clang::ConstructJob`).  There the Xclang options are all gathered and forwarded at a particular spot in the command line for cc1.  They aren't interleaved with other options, and it wouldn't really make sense to do so anyway since it doesn't really look like cc1 arguments are constructed from driver arguments in any particular order.
>
> The llvm/lib/Option/OptTable.cpp code is not really setup to easily interleave arguments like would be required for your request.  Can you see a way to accomplish what you want without a deep refactoring of OptTable::ParseArgs and the InputArgList class?


Okay, if it's hard to do, I suppose collecting the /clang: options and processing them separately after the others is the second-best option. We'll need to make sure the behaviour is well-documented.


https://reviews.llvm.org/D53457