Eric Fiselier 708afb56c1 Implement __builtin_LINE() et. al. to support source location capture.
Summary:
This patch implements the source location builtins `__builtin_LINE(), `__builtin_FUNCTION()`, `__builtin_FILE()` and `__builtin_COLUMN()`. These builtins are needed to implement [`std::experimental::source_location`](https://rawgit.com/cplusplus/fundamentals-ts/v2/main.html#reflection.src_loc.creation).

With the exception of `__builtin_COLUMN`, GCC also implements these builtins, and Clangs behavior is intended to match as closely as possible. 

Reviewers: rsmith, joerg, aaron.ballman, bogner, majnemer, shafik, martong

Reviewed By: rsmith

Subscribers: rnkovacs, loskutov, riccibruno, mgorny, kunitoki, alexr, majnemer, hfinkel, cfe-commits

Differential Revision: https://reviews.llvm.org/D37035

llvm-svn: 360937
2019-05-16 21:04:15 +00:00
..
2018-12-04 14:34:09 +00:00

//===----------------------------------------------------------------------===//
// C Language Family Front-end
//===----------------------------------------------------------------------===//

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