[llvm] [ADT] Make null PointerUnion with different active members compare equal (PR #121847)

[Sergei Barannikov via llvm-commits]

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@@ -208,6 +208,11 @@ TEST_F(PointerUnionTest, NewCastInfra) {
   EXPECT_FALSE(isa<float *>(d4null));
   EXPECT_FALSE(isa<long long *>(d4null));
 
+  EXPECT_FALSE(isa_and_present<int *>(i4null));
+  EXPECT_FALSE(isa_and_present<float *>(f4null));
+  EXPECT_FALSE(isa_and_present<long long *>(l4null));
+  EXPECT_FALSE(isa_and_present<double *>(d4null));
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s-barannikov wrote:

Previously, only the first `isa_and_present` returned false.


https://github.com/llvm/llvm-project/pull/121847