[clang] [Clang][RFC] Intrododuce a builtin to determine the structure binding size (PR #131515)

[Erich Keane via cfe-commits]

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@@ -1873,19 +1874,54 @@ TypeTraitExpr::TypeTraitExpr(QualType T, SourceLocation Loc, TypeTrait Kind,
   setDependence(computeDependence(this));
 }
 
+TypeTraitExpr::TypeTraitExpr(QualType T, SourceLocation Loc, TypeTrait Kind,
+                             ArrayRef<TypeSourceInfo *> Args,
+                             SourceLocation RParenLoc, APValue Value)
+    : Expr(TypeTraitExprClass, T, VK_PRValue, OK_Ordinary), Loc(Loc),
+      RParenLoc(RParenLoc) {
+  assert(Kind <= TT_Last && "invalid enum value!");
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erichkeane wrote:

Seems like this is ripe for a `init` function, and just set the values/IsBooleanTypeTrait in these.  They are otherwise copy/paste, right?

https://github.com/llvm/llvm-project/pull/131515