Prefer using '-std=gnu++11' over '-std=c++11' when available, as NetBSD
exposes the correct alloca() implementation only with gnu* C/C++
standards.
Differential Revision: https://reviews.llvm.org/D55477
llvm-svn: 348854
These are needed by both libraries, so we can do that in a
common namespace and unify configuration parameters.
Also make sure that the user isn't requesting libomptarget
if the library cannot be built on the system. Issue an error
in that case.
Differential Revision: https://reviews.llvm.org/D40081
llvm-svn: 319342