[quanto]

> It utilizes a range of Modern Fortran features, including extensive use of optional variables, function pointer passing, and a randomized test driver, among others. Successfully compiling PRIMA requires a compiler with a robust and mature backend, as well as well-developed intermediate passes and a capable parser.

I am not getting a full picture here. What's challenging about PRIMA code base? Does it use some advanced features that are difficult for a compiler to support? Are the mentioned features in the 2008 standard?

What's actually impressive is that LFortran in alpha stage is only 2x slower than GFortran, which goes back decades.

[certik]

It was a lot of corner cases that we had to get right, it's the most advanced code that LFortran can compile. I think none of the features individually is difficult to support, but there were a lot of them.