RFC: `fsyntax-only` as an alias for `fparse-only` in `f18`

Subprojects Flang
1

Hi all,

Recently we've ported the preprocessor tests to use the new Flang driver[1]. Soon we will be ready to port OpenMP and OpenACC tests. As the new driver and `f18` use slightly different spellings for options [2], we will require some workarounds. In this RFC I'd like to ask you for your opinion on using `-fparse-only` and `-fsyntax-only`.

In [3] we introduce `-fsyntax-only` as an alias for `-fparse-only` in `f18`. This is sufficient for us to start porting more tests to the new Flang driver very soon. Also, in [3] we port all tests to use `-fsyntax-only` instead of `-fparse-only`. Otherwise, `-fparse-only` remains supported by `f18` and you can continue to use it.

Does the approach from [3] work for you or would you prefer a different solution? I'm happy to propose some alternatives if there's interest.

Thank you for reading!

-Andrzej

[1] https://reviews.llvm.org/D94805
[2] [flang-dev] RFC: new Flang driver options
[3] ⚙ D95784 [flang][f18] Replace `-fparse-only` with `-fsyntax-only`

2

+1 for -fsyntax-only, consistency with Clang is worth it.

An alias for a while seems reasonable, eventually we phase alternatives out.

~ Johannes

3

+1 from me also. Seems like an obvious good thing to ease the transition from old driver to new and the new spelling was already agreed in your previous RFC.

4

Thank you both! There was an additional suggestion on Slack to remove `-fparse-only` entirely, but I prefer to do it in 2 steps. If this is fine with you, could you please review and approve?

Btw, I've updated the patch to make it clear that `-fparse-only` is deprecated. Users will also see this warning:

warning: `-fparse-only` is deprecated and will be removed in the future, use `-fsyntax-only` instead

-Andrzej