[flang-rt] Remove experiemental OpenMP offloading support (#183653) Summary: This, as far as I am aware, has mostly been superceded by the runtimes build that's built on top of libc. This build links 30% faster, supports more functionality, and uses 95% less disk space, so it seems to be the direction we want to go. CUDA support remains, this is not needed urgently. GitOrigin-RevId: 8e40387ce4ad6dc1635c6cd7cdeea8157297569f
Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.
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Read more about flang in the docs directory. Start with the compiler overview.
To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.
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To understand the compilers handling of intrinsics, see the discussion of intrinsics.
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