OpenMP for clang/flang and gcc--

Hi Ports@

Brian Callahan published a draft OpenMP port a few weeks ago and I've
been working on it, to get both C and Fortran-9x working with
clang/flang and gcc/f95 co-existing.

The current issues are:

1 the openmp port is from llvm.org and creates a GNU-compatible OpenMP
library libgomp but gcc can create it's own. The names conflict
(libgomp from both). Normally flang/clang would use libomp if the
compatibility is disabled.

2 flang and clang don't appear to need the GNU-extensions. Flang (and
Clang) appear to support -fopenmp options out-of-the-box.

3 gcc--%8 is built without building libgomp (--disable-libgomp) but does
support -fopenmp (as of -current).

Does anyone know why --disable-libgomp is used in gcc--%8? Also, is
there any reason to provide libgomp for flang/clang?


thanks in advance

--John