[clang] [flang] [clang][Driver] Add RPATH by default (PR #115286)

[David Truby via cfe-commits]

DavidTruby wrote:

I'd argue that this provides the least surprising behaviour to the end user: building a file with `clang -fopenmp` or `clang++ -stdlib=libc++` where openmp/libc++ were enabled on that LLVM build gives a binary that can just be run on that system, without setting any environment variables or playing with anything else. It seems to me that clang-built binaries should know where to look for the libraries from that toolchain. GCC does this with libstdc++ and libgcc_s as far as I know (I haven't checked in a while so I could be wrong here).

https://github.com/llvm/llvm-project/pull/115286