[clang] [clang][ExprConst] Reject field access with nullptr base (PR #113885)

[Timm Baeder via cfe-commits]

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@@ -1703,7 +1703,7 @@ namespace {
     bool checkNullPointerDiagnosingWith(const GenDiagType &GenDiag) {
       if (Designator.Invalid)
         return false;
-      if (IsNullPtr) {
+      if (getLValueBase().isNull()) {
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tbaederr wrote:

The offset is added in `adjustOffset()`, which calls `clearIsNullPointer()`. This is called _before_ we call `addDecl()`, so at that point the pointer is already considered non-null.

https://github.com/llvm/llvm-project/pull/113885