[clang] nonblocking/nonallocating attributes (was: nolock/noalloc) (PR #84983)

[via cfe-commits]

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@@ -768,6 +776,18 @@ class Sema final : public SemaBase {
   /// Warn when implicitly casting 0 to nullptr.
   void diagnoseZeroToNullptrConversion(CastKind Kind, const Expr *E);
 
+  // ----- function effects ---
+
+  /// Warn when implicitly changing function effects.
+  void diagnoseFunctionEffectConversion(QualType DstType, QualType SrcType,
+                                        SourceLocation Loc);
+
+  /// Try to parse the conditional expression attached to an effect attribute
+  /// (e.g. 'nonblocking'). (c.f. Sema::ActOnNoexceptSpec). If RequireConstexpr,
+  /// then this will fail if the expression is dependent.
+  ExprResult ActOnEffectExpression(Expr *CondExpr, FunctionEffectMode &Mode,
+                                   bool RequireConstexpr = false);
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Sirraide wrote:

What is the `RequireConstexpr` parameter for? It’s always `false` from what I can tell.

https://github.com/llvm/llvm-project/pull/84983