[clang] [clang][CGRecordLayout] Remove dependency on isZeroSize (PR #96422)

[David Blaikie via cfe-commits]

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@@ -185,6 +203,18 @@ CALL_AO(PackedMembers)
 // CHECK: call void @llvm.memcpy.p0.p0.i64({{.*}} align 1 {{.*}} align 1 {{.*}}i64 16, i1 {{.*}})
 // CHECK: ret ptr
 
+// WithEmptyField copy-assignment:
+// CHECK-LABEL: define linkonce_odr nonnull align {{[0-9]+}} dereferenceable({{[0-9]+}}) ptr @_ZN14WithEmptyFieldaSERKS_
+// CHECK: call void @llvm.memcpy.p0.p0.i64({{.*}} align 4 {{.*}} align 4 {{.*}}i64 4, i1 {{.*}})
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dwblaikie wrote:

Sorry, jumping in here without a lot of context, but the change in `%struct.WithEmptyField` seems wrong, doesn't it? Like that is a change in layout/ABI break/bad thing? I guess I'm missing something about why that change in layout would be acceptable? (maybe padding - if NonPOD gets aligned, such that the structure isn't changing layout after all?)

https://github.com/llvm/llvm-project/pull/96422