[clang] [clang][ExprConst] Consider integer pointers of value 0 nullptr (PR #150164)

[Timm Baeder via cfe-commits]

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@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -triple amdgcn -cl-std=clc++ -verify %s
+
+// expected-no-diagnostics
+
+#define fold(x) (__builtin_constant_p(x) ? (x) : (x))
+static_assert(nullptr != fold(reinterpret_cast<private int*>(0)));
+
+static_assert(nullptr == (private int *)0);
+
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tbaederr wrote:

The fact that the two casts behave differently seems weird, but the second one is a `NullToPointer` cast.

https://github.com/llvm/llvm-project/pull/150164