[clang] [Clang][Sema] Ensure explicitly defaulted functions respect FP pragmas from their declaration site (PR #207429)

[Erich Keane via cfe-commits]

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@@ -2049,13 +2049,17 @@ class FunctionDecl : public DeclaratorDecl,
 
   };
 
-  /// Stashed information about a defaulted/deleted function body.
+  /// Stashed information about a defaulted/deleted function body, including
+  /// the active FP pragma overrides (FPOptionsOverride) from the declaration
+  /// site. These overrides are required to correctly synthesize the function
+  /// body.
   class DefaultedOrDeletedFunctionInfo final
       : llvm::TrailingObjects<DefaultedOrDeletedFunctionInfo, DeclAccessPair,
                               StringLiteral *> {
     friend TrailingObjects;
     unsigned NumLookups;
     bool HasDeletedMessage;
+    uint64_t FPFeatures;
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erichkeane wrote:

Why a uint64_t instead of the actual `FPOptionsOverride` type? 

https://github.com/llvm/llvm-project/pull/207429