[llvm-branch-commits] [flang] [Flang][OMP] Replace SUM intrinsic call with SUM operations (PR #113082)

[Michael Klemm via llvm-branch-commits]

mjklemm wrote:

> * The above requirement basically breaks allowing users to pick their own openmp library when compiling their application. I'm not sure how widely used this is.

They won't be able to that regardless.  The OpenMP library will have to match what Flang is using; otherwise, two OpenMP implementations will co-exist in the same process and that's usually a recipe for problems.

Regarding the initial question: I'm ambivalent on the direction (runtime entry point vs. code-gen).  I will say though that if we go with the runtime entry point, we will tie the Fortran runtime to the OpenMP runtime, which may not be desired in all cases. 

https://github.com/llvm/llvm-project/pull/113082