[flang] Process pointer component default initializers sooner

flang/docs/Extensions.md

@@ -875,6 +875,13 @@ print *, [(j,j=1,10)]
   compilers) and don't use any defined unformatted WRITE that might have been
   defined.
 
+* Forward references to target objects are allowed to appear
+  in the initializers of data pointer declarationss.
+  Forward references to target objects are not accepted in the default
+  initializers of derived type component declarations, however,
+  since these default values need to be available to process incomplete
+  structure constructors.
+
 ## De Facto Standard Features
 
 * `EXTENDS_TYPE_OF()` returns `.TRUE.` if both of its arguments have the

flang/lib/Semantics/resolve-names.cpp

@@ -5383,7 +5383,7 @@ void DeclarationVisitor::Post(const parser::EntityDecl &x) {
     ConvertToObjectEntity(symbol) || ConvertToProcEntity(symbol);
     symbol.set(
         Symbol::Flag::EntryDummyArgument, false); // forestall excessive errors
-    Initialization(name, *init, false);
+    Initialization(name, *init, /*inComponentDecl=*/false);
   } else if (attrs.test(Attr::PARAMETER)) { // C882, C883
     Say(name, "Missing initialization for parameter '%s'"_err_en_US);
   }
@@ -6398,7 +6398,7 @@ void DeclarationVisitor::Post(const parser::ComponentDecl &x) {
     SetCUDADataAttr(name.source, symbol, cudaDataAttr());
     if (symbol.has<ObjectEntityDetails>()) {
       if (auto &init{std::get<std::optional<parser::Initialization>>(x.t)}) {
-        Initialization(name, *init, true);
+        Initialization(name, *init, /*inComponentDecl=*/true);
       }
     }
     currScope().symbol()->get<DerivedTypeDetails>().add_component(symbol);
@@ -8933,9 +8933,13 @@ void DeclarationVisitor::Initialization(const parser::Name &name,
             // Defer analysis to the end of the specification part
             // so that forward references and attribute checks like SAVE
             // work better.
-            auto restorer{common::ScopedSet(deferImplicitTyping_, true)};
-            Walk(target);
-            ultimate.set(Symbol::Flag::InDataStmt);
+            if (inComponentDecl) {
+              PointerInitialization(name, target);
+            } else {
+              auto restorer{common::ScopedSet(deferImplicitTyping_, true)};
+              Walk(target);
+              ultimate.set(Symbol::Flag::InDataStmt);
+            }
           },
           [&](const std::list<Indirection<parser::DataStmtValue>> &values) {
             // Handled later in data-to-inits conversion
@@ -10355,11 +10359,6 @@ class DeferredCheckVisitor {
         std::get<std::optional<parser::Initialization>>(decl.t));
     return false;
   }
-  bool Pre(const parser::ComponentDecl &decl) {
-    Init(std::get<parser::Name>(decl.t),
-        std::get<std::optional<parser::Initialization>>(decl.t));
-    return false;
-  }
   bool Pre(const parser::ProcDecl &decl) {
     if (const auto &init{
             std::get<std::optional<parser::ProcPointerInit>>(decl.t)}) {

flang/test/Semantics/bug1056.f90

@@ -0,0 +1,13 @@
+! RUN: %flang_fc1 -fdebug-unparse %s | FileCheck %s
+program bug
+  integer, target :: ita(2) = [1,2], itb(2) = [3,4], itc(2) = [5,6]
+  type t1
+    integer, pointer :: p1(:) => ita, p2(:) => itb
+  end type
+  type t2
+    !CHECK: TYPE(t1) :: comp = t1(p1=itc,p2=itb)
+    type(t1) :: comp = t1(itc)
+  end type
+  integer, pointer :: p3(:) => itd
+  integer, target :: itd(2) = [7,8]
+end

flang/test/Semantics/symbol15.f90

@@ -43,6 +43,9 @@ subroutine iface
  !DEF: /m/pp6 EXTERNAL, POINTER, PUBLIC (Subroutine) ProcEntity
  !DEF: /m/modproc1 PUBLIC (Subroutine) Subprogram
  procedure(iface), pointer :: pp6 => modproc1
+ !DEF: /m/xx PUBLIC, TARGET ObjectEntity REAL(4)
+ !DEF: /m/yy PUBLIC, TARGET ObjectEntity REAL(4)
+ real, target :: xx, yy(2)
  !DEF: /m/t1 PUBLIC DerivedType
  type :: t1
   !DEF: /m/t1/opc1 POINTER ObjectEntity REAL(4)
@@ -51,11 +54,11 @@ subroutine iface
   !REF: /m/null
   real, pointer :: opc2 => null()
   !DEF: /m/t1/opc3 POINTER ObjectEntity REAL(4)
-  !REF: /m/x
-  real, pointer :: opc3 => x
+  !REF: /m/xx
+  real, pointer :: opc3 => xx
   !DEF: /m/t1/opc4 POINTER ObjectEntity REAL(4)
-  !REF: /m/y
-  real, pointer :: opc4 => y(1)
+  !REF: /m/yy
+  real, pointer :: opc4 => yy(1)
   !REF: /m/iface
   !DEF: /m/t1/ppc1 NOPASS, POINTER (Subroutine) ProcEntity
   procedure(iface), nopass, pointer :: ppc1
@@ -101,12 +104,12 @@ subroutine iface
   !REF: /m/null
   real, pointer :: opc2 => null()
   !DEF: /m/pdt1/opc3 POINTER ObjectEntity REAL(4)
-  !REF: /m/x
-  real, pointer :: opc3 => x
+  !REF: /m/xx
+  real, pointer :: opc3 => xx
   !DEF: /m/pdt1/opc4 POINTER ObjectEntity REAL(4)
-  !REF: /m/y
+  !REF: /m/yy
   !REF: /m/pdt1/k
-  real, pointer :: opc4 => y(k)
+  real, pointer :: opc4 => yy(k)
   !REF: /m/iface
   !DEF: /m/pdt1/ppc1 NOPASS, POINTER (Subroutine) ProcEntity
   procedure(iface), nopass, pointer :: ppc1

t.f90

@@ -0,0 +1,11 @@
+integer, target :: ita(2) = [1,2], itb(2) = [3,4], itc(2) = [5,6]
+type t1
+  integer, pointer :: p1(:) => ita, p2(:) => itb
+end type
+type t2
+  type(t1) :: comp = t1(itc)
+end type
+type(t2) :: var
+print *, var%comp%p2
+var%comp = t1(itc)
+end