[clang] [clang] Fix crashes when initializing constexpr int* with floating-point (PR #180376)

[Samrudh Nelli via cfe-commits]

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@@ -8503,8 +8503,12 @@ ExprResult InitializationSequence::Perform(Sema &S,
         Expr::EvalResult ER;
         if (Entity.getType()->getAs<PointerType>() &&
             CurInit.get()->EvaluateAsRValue(ER, S.Context) &&
-            !ER.Val.isNullPointer()) {
+            // We continue and let it error later if Rvalue is not a pointer
+            ER.Val.isLValue() && 
+            !ER.Val.isNullPointer() &&
+            !ER.Val.getLValueBase().isNull()) {
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SamrudhNelli wrote:

I originally added !getLValueBase().isNull() to preserve the existing error message for int values rather than returning the new error message (intended for floats). This was due to the reason that int values return true for Lvalue() and getValueBase().isNull().

https://github.com/llvm/llvm-project/pull/180376