[clang] Avoid printing overly large integer. (PR #75902)

[Jon Roelofs via cfe-commits]

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@@ -17132,6 +17132,9 @@ static bool ConvertAPValueToString(const APValue &V, QualType T,
         case BuiltinType::WChar_U: {
           unsigned TyWidth = Context.getIntWidth(T);
           assert(8 <= TyWidth && TyWidth <= 32 && "Unexpected integer width");
+          if (V.getInt() >= (1 << 64)) {
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jroelofs wrote:

> 1<<64 is results 0

Shifting beyond the width of the type is Undefined Behavior.

https://github.com/llvm/llvm-project/pull/75902