[flang] Handle DATA-style default component /inits/ in time (#159469)

DEC-style default component initializers that use DATA statement syntax
aren't processed until DATA statement values are converted into init()
expressions in the symbol table. Part of that conversion process
involves combining storage-associated (EQUIVALENCE) symbols with
compiler-generated symbols with initialization when the associated
symbols have initialization, and part of that process involves the
application of default component initializers; so we need to make sure
that they've already been processed.

(Fixes Fujitsu Fortran test 0633_0004.f.)

Author: klausler

flang/lib/Semantics/data-to-inits.cpp

@@ -943,10 +943,19 @@ void ConstructInitializer(const Symbol &symbol,
 
 void ConvertToInitializers(
     DataInitializations &inits, evaluate::ExpressionAnalyzer &exprAnalyzer) {
+  // Process DATA-style component /initializers/ now, so that they appear as
+  // default values in time for EQUIVALENCE processing in ProcessScopes.
+  for (auto &[symbolPtr, initialization] : inits) {
+    if (symbolPtr->owner().IsDerivedType()) {
+      ConstructInitializer(*symbolPtr, initialization, exprAnalyzer);
+    }
+  }
   if (ProcessScopes(
           exprAnalyzer.context().globalScope(), exprAnalyzer, inits)) {
     for (auto &[symbolPtr, initialization] : inits) {
-      ConstructInitializer(*symbolPtr, initialization, exprAnalyzer);
+      if (!symbolPtr->owner().IsDerivedType()) {
+        ConstructInitializer(*symbolPtr, initialization, exprAnalyzer);
+      }
     }
   }
 }

flang/test/Semantics/data24.f90

@@ -0,0 +1,16 @@
+! RUN: %flang_fc1 -fdebug-dump-symbols %s 2>&1 | FileCheck %s
+! Ensure that DATA-style default component /initializers/ are processed
+! before they are needed to handle EQUIVALENCE'd storage.
+type t
+  sequence
+  integer :: j(10) /1,2,3,4,5,6,7,8,9,10/
+end type
+type(t) :: A
+integer arr(10)
+equivalence (A, arr)
+end
+
+!CHECK: .F18.0, SAVE (CompilerCreated) size=40 offset=0: ObjectEntity type: INTEGER(4) shape: 1_8:10_8 init:[INTEGER(4)::1_4,2_4,3_4,4_4,5_4,6_4,7_4,8_4,9_4,10_4]
+!CHECK: a size=40 offset=0: ObjectEntity type: TYPE(t)
+!CHECK: arr size=40 offset=0: ObjectEntity type: INTEGER(4) shape: 1_8:10_8
+!CHECK: Equivalence Sets: (a,arr(1)) (.F18.0,a)