[llvm-branch-commits] [clang] [clang][builtin] Implement __builtin_allow_runtime_check (PR #87568)

[Aaron Ballman via llvm-branch-commits]

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@@ -3233,6 +3233,17 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
     if (BuiltinCountZeroBitsGeneric(*this, TheCall))
       return ExprError();
     break;
+
+  case Builtin::BI__builtin_allow_runtime_check: {
+    Expr *Arg = TheCall->getArg(0);
+    // Check if the argument is a string literal.
+    if (!isa<StringLiteral>(Arg->IgnoreParenImpCasts())) {
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AaronBallman wrote:

This might be a reasonable restriction, but consider other cases like: `constexpr` variable of string type, `constexpr` function call that returns a `const char *`, `_Generic` that results in a string constant, etc. Would those be reasonable to support?

https://github.com/llvm/llvm-project/pull/87568