[llvm] [flang] Don't associate pointers with zero sized storage targets (PR #155867)

[Peter Klausler via llvm-commits]

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@@ -67,8 +67,12 @@ void RTDEF(PointerAssociateScalar)(Descriptor &pointer, void *target) {
 }
 
 void RTDEF(PointerAssociate)(Descriptor &pointer, const Descriptor &target) {
-  pointer = target;
-  pointer.raw().attribute = CFI_attribute_pointer;
+  if (target.ElementBytes() > 0) {
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klausler wrote:

This would leave the pointer unchanged when the target is an empty storage sequence, which would be wrong.

https://github.com/llvm/llvm-project/pull/155867