Neat, another fortran compiler option.
Does anyone have a list/comparison of all the LLVM fortran compilers? I'm not really tracking this, since Fortran isn't really my area of expertise, but I've seen the following. Perhaps there are even more?
"Flang". The original of the name, I think? Abandoned.
"Fort" -- fork of the above flang, renamed. Seems active.
"Flag". Different from the other "flang". Active, but deprecated in favor of f18.
"f18". Rewrite-from-scratch (?) of adjacent "flang". Active, but not fully-functional yet (I think?).
"FC". Newly-developed, independent of the other compilers. Active. (But this source-code dates from the previous announcement, not yet updated with latest developments):
I don't know how any of these compare with each other, nor why we have so many. I have no opinion on which or whether any of these should be "blessed", nor do I really want to become educated enough on this topic to gain such an opinion personally.
But, given that there appear to be at least 3 fortran compilers under active development by different people, I would love to be reassured that such a comparison has been done, and that we are selecting one of them for good reasons. It'd be great if someone (or multiple someones) could post a summary/comparison of what these things all are, and why one is the right path forward vs another.
I don't view what we're doing, or should be doing, as selecting one of them. We should have a Fortran frontend in the LLVM project. It should be called Flang. It should be developed by a broad subset of our LLVM community.
A decision was made that it would be reasonable to import from the f18 project to start this process, in part because the founding purpose of the f18 activity was to produce a modern Fortran compiler in modern C++ that would fit with the LLVM community. Its development process has been open, many of us have been involved, and so on. Very important, however, is that it's under active development and that it's far from done. I want the design and implementation of the Frontend to be an LLVM community effort, and the best way for that to happen is for the process to happen under the umbrella of the LLVM project. Critically, this is what those involved the current f18 development actively desire.
I can't say all of the same about the other projects. However, I think that it is important to make clear that LLVM's Flang project is a community project and everyone who wishes to be a part of that community is welcome. As I see it, we now have a significant pool of people with LLVM/Fortran development experience who can, if they choose, contribute to our effort, and I actively encourage them to do so. That means that we might end up doing some things more-or-less like f18 does them now, and we might end up doing other things more-or-less like FC does them now, and so on. It all depends on who contributes and what feedback they receive from everyone else.