[cfe-dev] [RFC] Adding support for the flang toolchain

[Joerg Sonnenberger via cfe-dev]

On Mon, Dec 18, 2017 at 05:40:31PM -0600, xoviat wrote:
> > I did a review of the changes half a year ago. There was quite a bit of
> > unnecessary churn in the repo. The biggest problem from my perspective
> > is the massive use of magic numbers in the interface. I think that part
> > should be fixed on the flang side before talking about merging the
> > patches.
> 
> For the record, the churn has settled down quite a bit (maybe ~15 lines of
> changes per month now).

I meant more that the clang fork contained quite a few purely cosmetical
changes, not that it changed regulary.

> The magic numbers still appear to be present though; that would need to
> be fixed. However, while that's in progress, are there any other
> potential issues that need to be resolved as well (I'd like
> to tackle them all at once rather than iterating)?

Iteration is likely unavoidable. Ideally, a large part of the option
handling should be table-driven and not hard-coded. The toolchain part
needed a lot of refactoring in the version I checked.

One high-level question is whether shoe-horning the
gfortran-compatibility interface into the clang driver is really
desirable. I.e. it is a mostly orthogonal set of command line flags and
that seems pretty bad from a design perspective. It's likely going to
repeat the problems of clang-cl.exe over and over again. I'd like some
input from folks like Hal on the impact on the UX here. In other words,
I wonder if having a consistent and integrated approach and maybe a
compat-wrapper script as flang isn't better long term.

Joerg