Dmitry Babokin

I see no way to specify for `find_package(OpenMP)` that it needs llvm version. Not sure how to fix that properly.

> The way we were doing it was not portable _"for a reason"_: we don't want to use Gomp because the performance isn't good. Yeah, totally understand. Showing up of...

I file CMake issue for that: https://gitlab.kitware.com/cmake/cmake/-/issues/26263

To call external (non-ispc functions), you need to declare them as ``extern "C"``, as you would do in C. See more details here: http://ispc.github.io/ispc.html#interoperability-overview

For the dead code paths it's a different story, it needs to be a compiler recognised intrinsic. We don't have such intrinsic. Generally speaking, adding it is not difficult and...

To give more background for the issue, I'm pasting the code from mail thread: ```C static inline uniform int packed_store_active_float(uniform float dst[], float v) { return packed_store_active((int*)dst, intbits(v)); } uniform...

Here's the stack: ```bash #0 0x00000037eac35935 in raise () from /lib64/libc.so.6 #1 0x00000037eac370e8 in abort () from /lib64/libc.so.6 #2 0x000000000058a1f2 in FatalError (file=0x1762b0b "func.cpp", line=439, message=0x1762dd0 "Function verificication failed") at...

Note that we changes this part of short vectors definition several times forth and back - every time by users requests. And every time we broke something. It's quite sensitive...

I think there are two different things here to consider: - the size the data occupies when it's a part of a `struct` - i.e. how much padding it needs...

`2954.ispc` started passing for me with LLVM trunk (I'm on `5c20891b2`).