[flang] [llvm] [flang][runtime] Handle ALLOCATE(..., short SOURCE=) (PR #155715)

[Eugene Epshteyn via llvm-commits]

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@@ -743,22 +743,35 @@ RT_API_ATTRS void DoFromSourceAssign(Descriptor &alloc,
   if (alloc.rank() > 0 && source.rank() == 0) {
     // The value of each element of allocate object becomes the value of source.
     DescriptorAddendum *allocAddendum{alloc.Addendum()};
-    const typeInfo::DerivedType *allocDerived{
-        allocAddendum ? allocAddendum->derivedType() : nullptr};
     SubscriptValue allocAt[maxRank];
     alloc.GetLowerBounds(allocAt);
-    if (allocDerived) {
+    std::size_t allocElementBytes{alloc.ElementBytes()};
+    if (const typeInfo::DerivedType *allocDerived{
+            allocAddendum ? allocAddendum->derivedType() : nullptr}) {
+      // Handle derived type or short character source
       for (std::size_t n{alloc.InlineElements()}; n-- > 0;
           alloc.IncrementSubscripts(allocAt)) {
-        Descriptor allocElement{*Descriptor::Create(*allocDerived,
-            reinterpret_cast<void *>(alloc.Element<char>(allocAt)), 0)};
+        StaticDescriptor<maxRank, true, 8 /*?*/> statDesc;
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eugeneepshteyn wrote:

Why `/*?*/` ?

https://github.com/llvm/llvm-project/pull/155715