[clang] [llvm] [Clang] Show inlining hints for __attribute__((warning/error)) (PR #174892)

[Justin Stitt via llvm-commits]

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@@ -348,6 +348,13 @@ New Compiler Flags
 - New options for enabling allocation token instrumentation: ``-fsanitize=alloc-token``, ``-falloc-token-max=``, ``-fsanitize-alloc-token-fast-abi``, ``-fsanitize-alloc-token-extended``.
 - The ``-resource-dir`` option is now displayed in the list of options shown by ``--help``.
 - New option ``-fmatrix-memory-layout`` added to control the memory layout of Clang matrix types. (e.g. ``-fmatrix-memory-layout=column-major`` or ``-fmatrix-memory-layout=row-major``).
+- New option ``-fdiagnostics-show-inlining-chain`` added to show inlining chain
+  notes for ``[[gnu::warning]]`` and ``[[gnu::error]]`` diagnostics. When a
+  function with these attributes is called from an inlined context, Clang can
+  now show which functions were inlined to reach the call. When debug info is
+  available (``-gline-directives-only`` (implicitly enabled at ``-g1``) or
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JustinStitt wrote:

Done in [`1a22581` (#174892)](https://github.com/llvm/llvm-project/pull/174892/commits/1a2258184323622af390946c70b63afb12762276). I also added the note to the diagnostic note that gets emitted when in heuristic mode.

https://github.com/llvm/llvm-project/pull/174892