[clang] [Clang] use constant evaluation context for constexpr if conditions (PR #123667)

[Younan Zhang via cfe-commits]

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@@ -309,6 +309,7 @@ Bug Fixes to AST Handling
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 - Fixed type checking when a statement expression ends in an l-value of atomic type. (#GH106576)
 - Fixed uninitialized use check in a lambda within CXXOperatorCallExpr. (#GH129198)
+- Clang now correctly parses ``if constexpr`` expressions in immediate function context. (#GH123524)
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zyn0217 wrote:

This should go in the "Bug fixes to C++ support" column

https://github.com/llvm/llvm-project/pull/123667