[clang] [Clang][WIP] Constant Expressions inside of gcc'asm strings (PR #131003)

[Erich Keane via cfe-commits]

================
@@ -8552,25 +8552,39 @@ template<typename Derived>
 StmtResult
 TreeTransform<Derived>::TransformGCCAsmStmt(GCCAsmStmt *S) {
 
+
   SmallVector<Expr*, 8> Constraints;
   SmallVector<Expr*, 8> Exprs;
   SmallVector<IdentifierInfo *, 4> Names;
 
-  ExprResult AsmString;
   SmallVector<Expr*, 8> Clobbers;
 
   bool ExprsChanged = false;
 
+  auto RebuildString = [&] (Expr* E) {
+      ExprResult Result = getDerived().TransformExpr(E);
+      if (Result.isInvalid())
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erichkeane wrote:

```suggestion
      if (!Result.isUsable())
```

https://github.com/llvm/llvm-project/pull/131003