[Patch, fortran PR89645/99065 No IMPLICIT type error with: ASSOCIATE( X => function() )

Message ID CAGkQGiLh4RyAki7FV8vVLJDZydqT3hcaLKyMFjt4qvkEmWQiLg@mail.gmail.com
State Unresolved
Headers
Series [Patch, fortran PR89645/99065 No IMPLICIT type error with: ASSOCIATE( X => function() ) |

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Commit Message

Paul Richard Thomas Jan. 6, 2024, 5:26 p.m. UTC
  These PRs come about because of gfortran's single pass parsing. If the
function in the title is parsed after the associate construct, then its
type and rank are not known. The point at which this becomes a problem is
when expressions within the associate block are parsed. primary.cc
(gfc_match_varspec) could already deal with intrinsic types and so
component references were the trigger for the problem.

The two major parts of this patch are the fixup needed in gfc_match_varspec
and the resolution of  expressions with references in resolve.cc
(gfc_fixup_inferred_type_refs). The former relies on the two new functions
in symbol.cc to search for derived types with an appropriate component to
match the component reference and then set the associate name to have a
matching derived type. gfc_fixup_inferred_type_refs is called in resolution
and so the type of the selector function is known.
gfc_fixup_inferred_type_refs ensures that the component references use this
derived type and that array references occur in the right place in
expressions and match preceding array specs. Most of the work in preparing
the patch was sorting out cases where the selector was not a derived type
but, instead, a class function. If it were not for this, the patch would
have been submitted six months ago :-(

The patch is relatively safe because most of the chunks are guarded by
testing for the associate name being an inferred type, which is set in
gfc_match_varspec. For this reason, I do not think it likely that the patch
will cause regressions. However, it is more than possible that variants not
appearing in the submitted testcase will throw up new bugs.

Jerry has already given the patch a whirl and found that it applies
cleanly, regtests OK and works as advertised.

OK for trunk?

Paul

Fortran: Fix class/derived type function associate selectors [PR87477]

2024-01-06  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran
PR fortran/87477
PR fortran/89645
PR fortran/99065
* class.cc (gfc_change_class): New function needed for
associate names, when rank changes or a derived type is
produced by resolution
* dump-parse-tree.cc (show_code_node): Make output for SELECT
TYPE more comprehensible.
* gfortran.h : Add 'gfc_association_list' to structure
'gfc_association_list'. Add prototypes for
'gfc_find_derived_types', 'gfc_fixup_inferred_type_refs' and
'gfc_change_class'. Add macro IS_INFERRED_TYPE.
* match.cc (copy_ts_from_selector_to_associate): Add bolean arg
'select_type' with default false. If this is a select type name
and the selector is a inferred type, build the class type and
apply it to the associate name.
(build_associate_name): Pass true to 'select_type' in call to
previous.
* parse.cc (parse_associate): If the selector is a inferred type
the associate name is too. Make sure that function selector
class and rank, if known, are passed to the associate name. If
a function result exists, pass its typespec to the associate
name.
* primary.cc (gfc_match_varspec): If a scalar derived type
select type temporary has an array reference, match the array
reference, treating this in the same way as an equivalence
member. If this is a inferred type with a component reference,
call 'gfc_find_derived_types' to find a suitable derived type.
* resolve.cc (resolve_variable): Call new function below.
(gfc_fixup_inferred_type_refs): New function to ensure that the
expression references for a inferred type are consistent with
the now fixed up selector.
(resolve_assoc_var): Ensure that derived type or class function
selectors transmit the correct arrayspec to the associate name.
(resolve_select_type): If the selector is an associate name of
inferred type and has no component references, the associate
name should have its typespec.
* symbol.cc (gfc_set_default_type): If an associate name with
unknown type has a selector expression, try resolving the expr.
(find_derived_types, gfc_find_derived_types): New functions
that search for a derived type with a given name.
* trans-expr.cc (gfc_conv_variable): Some inferred type exprs
escape resolution so call 'gfc_fixup_inferred_type_refs'.
* trans-stmt.cc (trans_associate_var): Tidy up expression for
'class_target'. Correctly handle selectors that are class array
references, passed as derived types.

gcc/testsuite/
PR fortran/87477
PR fortran/89645
PR fortran/99065
* gfortran.dg/associate_64.f90 : New test
  

Comments

Harald Anlauf Jan. 8, 2024, 9:53 p.m. UTC | #1
Hi Paul,

your patch looks already very impressive!

Regarding the patch as is, I am still trying to grok it, even with your
explanations at hand...

While the testcase works as advertised, I noticed that it exhibits a
runtime memleak that occurs for (likely) each case where the associate
target is an allocatable, class-valued function result.

I tried to produce a minimal testcase using class(*), which apparently
is not handled by your patch (it ICEs for me):

program p
   implicit none
   class(*), allocatable :: x(:)
   x = foo()
   call prt (x)
   deallocate (x)
   ! up to here no memleak...
   associate (var => foo())
     call prt (var)
   end associate
contains
   function foo() result(res)
     class(*), allocatable :: res(:)
     res = [42]
   end function foo
   subroutine prt (x)
     class(*), intent(in) :: x(:)
     select type (x)
     type is (integer)
        print *, x
     class default
        stop 99
     end select
   end subroutine prt
end

Traceback (truncated):

foo.f90:9:18:

     9 |     call prt (var)
       |                  1
internal compiler error: tree check: expected record_type or union_type
or qual_union_type, have function_type in gfc_class_len_get, at
fortran/trans-expr.cc:271
0x19fd5d5 tree_check_failed(tree_node const*, char const*, int, char
const*, ...)
         ../../gcc-trunk/gcc/tree.cc:8952
0xe1562d tree_check3(tree_node*, char const*, int, char const*,
tree_code, tree_code, tree_code)
         ../../gcc-trunk/gcc/tree.h:3652
0xe3e264 gfc_class_len_get(tree_node*)
         ../../gcc-trunk/gcc/fortran/trans-expr.cc:271
0xecda48 trans_associate_var
         ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2325
0xecdd09 gfc_trans_block_construct(gfc_code*)
         ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2383
[...]

I don't see anything wrong with it: NAG groks it, like Nvidia and Flang,
while Intel crashes at runtime.

Can you have another brief look?

Thanks,
Harald


On 1/6/24 18:26, Paul Richard Thomas wrote:
> These PRs come about because of gfortran's single pass parsing. If the
> function in the title is parsed after the associate construct, then its
> type and rank are not known. The point at which this becomes a problem is
> when expressions within the associate block are parsed. primary.cc
> (gfc_match_varspec) could already deal with intrinsic types and so
> component references were the trigger for the problem.
>
> The two major parts of this patch are the fixup needed in gfc_match_varspec
> and the resolution of  expressions with references in resolve.cc
> (gfc_fixup_inferred_type_refs). The former relies on the two new functions
> in symbol.cc to search for derived types with an appropriate component to
> match the component reference and then set the associate name to have a
> matching derived type. gfc_fixup_inferred_type_refs is called in resolution
> and so the type of the selector function is known.
> gfc_fixup_inferred_type_refs ensures that the component references use this
> derived type and that array references occur in the right place in
> expressions and match preceding array specs. Most of the work in preparing
> the patch was sorting out cases where the selector was not a derived type
> but, instead, a class function. If it were not for this, the patch would
> have been submitted six months ago :-(
>
> The patch is relatively safe because most of the chunks are guarded by
> testing for the associate name being an inferred type, which is set in
> gfc_match_varspec. For this reason, I do not think it likely that the patch
> will cause regressions. However, it is more than possible that variants not
> appearing in the submitted testcase will throw up new bugs.
>
> Jerry has already given the patch a whirl and found that it applies
> cleanly, regtests OK and works as advertised.
>
> OK for trunk?
>
> Paul
>
> Fortran: Fix class/derived type function associate selectors [PR87477]
>
> 2024-01-06  Paul Thomas  <pault@gcc.gnu.org>
>
> gcc/fortran
> PR fortran/87477
> PR fortran/89645
> PR fortran/99065
> * class.cc (gfc_change_class): New function needed for
> associate names, when rank changes or a derived type is
> produced by resolution
> * dump-parse-tree.cc (show_code_node): Make output for SELECT
> TYPE more comprehensible.
> * gfortran.h : Add 'gfc_association_list' to structure
> 'gfc_association_list'. Add prototypes for
> 'gfc_find_derived_types', 'gfc_fixup_inferred_type_refs' and
> 'gfc_change_class'. Add macro IS_INFERRED_TYPE.
> * match.cc (copy_ts_from_selector_to_associate): Add bolean arg
> 'select_type' with default false. If this is a select type name
> and the selector is a inferred type, build the class type and
> apply it to the associate name.
> (build_associate_name): Pass true to 'select_type' in call to
> previous.
> * parse.cc (parse_associate): If the selector is a inferred type
> the associate name is too. Make sure that function selector
> class and rank, if known, are passed to the associate name. If
> a function result exists, pass its typespec to the associate
> name.
> * primary.cc (gfc_match_varspec): If a scalar derived type
> select type temporary has an array reference, match the array
> reference, treating this in the same way as an equivalence
> member. If this is a inferred type with a component reference,
> call 'gfc_find_derived_types' to find a suitable derived type.
> * resolve.cc (resolve_variable): Call new function below.
> (gfc_fixup_inferred_type_refs): New function to ensure that the
> expression references for a inferred type are consistent with
> the now fixed up selector.
> (resolve_assoc_var): Ensure that derived type or class function
> selectors transmit the correct arrayspec to the associate name.
> (resolve_select_type): If the selector is an associate name of
> inferred type and has no component references, the associate
> name should have its typespec.
> * symbol.cc (gfc_set_default_type): If an associate name with
> unknown type has a selector expression, try resolving the expr.
> (find_derived_types, gfc_find_derived_types): New functions
> that search for a derived type with a given name.
> * trans-expr.cc (gfc_conv_variable): Some inferred type exprs
> escape resolution so call 'gfc_fixup_inferred_type_refs'.
> * trans-stmt.cc (trans_associate_var): Tidy up expression for
> 'class_target'. Correctly handle selectors that are class array
> references, passed as derived types.
>
> gcc/testsuite/
> PR fortran/87477
> PR fortran/89645
> PR fortran/99065
> * gfortran.dg/associate_64.f90 : New test
>
  
Paul Richard Thomas March 3, 2024, 4:04 p.m. UTC | #2
Hi Harald,

Please find an updated version of the patch that rolls in Steve's patch for
PR114141, fixes unlimited polymorphic function selectors and cures the
memory leaks. I apologise for not working on this sooner but, as I informed
you, I have been away for an extended trip to Australia.

The chunks that fix PR114141 are picked out in comment 14 to the PR and the
cures to the problems that you found in the first review are found at
trans-stmt.cc:2047-49.

Regtests fine. OK for trunk, bearing in mind that most of the patch is ring
fenced by the inferred_type flag?

Cheers

Paul


On Mon, 8 Jan 2024 at 21:53, Harald Anlauf <anlauf@gmx.de> wrote:

> Hi Paul,
>
> your patch looks already very impressive!
>
> Regarding the patch as is, I am still trying to grok it, even with your
> explanations at hand...
>
> While the testcase works as advertised, I noticed that it exhibits a
> runtime memleak that occurs for (likely) each case where the associate
> target is an allocatable, class-valued function result.
>
> I tried to produce a minimal testcase using class(*), which apparently
> is not handled by your patch (it ICEs for me):
>
> program p
>    implicit none
>    class(*), allocatable :: x(:)
>    x = foo()
>    call prt (x)
>    deallocate (x)
>    ! up to here no memleak...
>    associate (var => foo())
>      call prt (var)
>    end associate
> contains
>    function foo() result(res)
>      class(*), allocatable :: res(:)
>      res = [42]
>    end function foo
>    subroutine prt (x)
>      class(*), intent(in) :: x(:)
>      select type (x)
>      type is (integer)
>         print *, x
>      class default
>         stop 99
>      end select
>    end subroutine prt
> end
>
> Traceback (truncated):
>
> foo.f90:9:18:
>
>      9 |     call prt (var)
>        |                  1
> internal compiler error: tree check: expected record_type or union_type
> or qual_union_type, have function_type in gfc_class_len_get, at
> fortran/trans-expr.cc:271
> 0x19fd5d5 tree_check_failed(tree_node const*, char const*, int, char
> const*, ...)
>          ../../gcc-trunk/gcc/tree.cc:8952
> 0xe1562d tree_check3(tree_node*, char const*, int, char const*,
> tree_code, tree_code, tree_code)
>          ../../gcc-trunk/gcc/tree.h:3652
> 0xe3e264 gfc_class_len_get(tree_node*)
>          ../../gcc-trunk/gcc/fortran/trans-expr.cc:271
> 0xecda48 trans_associate_var
>          ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2325
> 0xecdd09 gfc_trans_block_construct(gfc_code*)
>          ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2383
> [...]
>
> I don't see anything wrong with it: NAG groks it, like Nvidia and Flang,
> while Intel crashes at runtime.
>
> Can you have another brief look?
>
> Thanks,
> Harald
>
>
> On 1/6/24 18:26, Paul Richard Thomas wrote:
> > These PRs come about because of gfortran's single pass parsing. If the
> > function in the title is parsed after the associate construct, then its
> > type and rank are not known. The point at which this becomes a problem is
> > when expressions within the associate block are parsed. primary.cc
> > (gfc_match_varspec) could already deal with intrinsic types and so
> > component references were the trigger for the problem.
> >
> > The two major parts of this patch are the fixup needed in
> gfc_match_varspec
> > and the resolution of  expressions with references in resolve.cc
> > (gfc_fixup_inferred_type_refs). The former relies on the two new
> functions
> > in symbol.cc to search for derived types with an appropriate component to
> > match the component reference and then set the associate name to have a
> > matching derived type. gfc_fixup_inferred_type_refs is called in
> resolution
> > and so the type of the selector function is known.
> > gfc_fixup_inferred_type_refs ensures that the component references use
> this
> > derived type and that array references occur in the right place in
> > expressions and match preceding array specs. Most of the work in
> preparing
> > the patch was sorting out cases where the selector was not a derived type
> > but, instead, a class function. If it were not for this, the patch would
> > have been submitted six months ago :-(
> >
> > The patch is relatively safe because most of the chunks are guarded by
> > testing for the associate name being an inferred type, which is set in
> > gfc_match_varspec. For this reason, I do not think it likely that the
> patch
> > will cause regressions. However, it is more than possible that variants
> not
> > appearing in the submitted testcase will throw up new bugs.
> >
> > Jerry has already given the patch a whirl and found that it applies
> > cleanly, regtests OK and works as advertised.
> >
> > OK for trunk?
> >
> > Paul
> ...snip...
  
Harald Anlauf March 3, 2024, 8:20 p.m. UTC | #3
Hi Paul,

welcome back!

On 3/3/24 17:04, Paul Richard Thomas wrote:
> Hi Harald,
> 
> Please find an updated version of the patch that rolls in Steve's patch for
> PR114141, fixes unlimited polymorphic function selectors and cures the
> memory leaks. I apologise for not working on this sooner but, as I informed
> you, I have been away for an extended trip to Australia.
> 
> The chunks that fix PR114141 are picked out in comment 14 to the PR and the
> cures to the problems that you found in the first review are found at
> trans-stmt.cc:2047-49.
> 
> Regtests fine. OK for trunk, bearing in mind that most of the patch is ring
> fenced by the inferred_type flag?

I would say that it is almost fine.

Two things that I found:

- Testcase associate_65.f90 does not compile with -std=f2023, because
   IMAG is a GNU extension, while AIMAG is the standard version.
   Could you please adjust that?

- I think the handling of parentheses and functions returning pointers
   does not work correctly.  Consider:


program paul
   implicit none
   type t
      integer :: i
   end type t
   type(t), pointer :: p(:)
   allocate (p(-3:3))

   associate (q => p)
     print *, lbound (q), ubound (q) ! Should print -3 3 (OK)
   end associate

   associate (q => set_ptr())
     print *, lbound (q), ubound (q) ! Should print -3 3 (OK)
   end associate

   associate (q => (p))
     print *, lbound (q), ubound (q) ! Should print 1 7 (OK)
   end associate

   associate (q => (set_ptr()))      ! <- are these parentheses lost?
     print *, lbound (q), ubound (q) ! Should print 1 7
   end associate
contains
   function set_ptr () result (res)
     type(t), pointer :: res(:)
     res => p
   end function set_ptr
end


While the first three variants give the right bounds, the last version
- after applying your patch - is mishandled and the testcase now prints:

           -3           3
           -3           3
            1           7
           -3           3

Both NAG and Intel support my expectation, namely that the last line
should equal the next-to-last.

Can you recheck the logic for that particular corner case?

With these points addressed, your patch is OK from my side.

Thanks for the patch and your endurance!

Harald


> Cheers
> 
> Paul
> 
> 
> On Mon, 8 Jan 2024 at 21:53, Harald Anlauf <anlauf@gmx.de> wrote:
> 
>> Hi Paul,
>>
>> your patch looks already very impressive!
>>
>> Regarding the patch as is, I am still trying to grok it, even with your
>> explanations at hand...
>>
>> While the testcase works as advertised, I noticed that it exhibits a
>> runtime memleak that occurs for (likely) each case where the associate
>> target is an allocatable, class-valued function result.
>>
>> I tried to produce a minimal testcase using class(*), which apparently
>> is not handled by your patch (it ICEs for me):
>>
>> program p
>>     implicit none
>>     class(*), allocatable :: x(:)
>>     x = foo()
>>     call prt (x)
>>     deallocate (x)
>>     ! up to here no memleak...
>>     associate (var => foo())
>>       call prt (var)
>>     end associate
>> contains
>>     function foo() result(res)
>>       class(*), allocatable :: res(:)
>>       res = [42]
>>     end function foo
>>     subroutine prt (x)
>>       class(*), intent(in) :: x(:)
>>       select type (x)
>>       type is (integer)
>>          print *, x
>>       class default
>>          stop 99
>>       end select
>>     end subroutine prt
>> end
>>
>> Traceback (truncated):
>>
>> foo.f90:9:18:
>>
>>       9 |     call prt (var)
>>         |                  1
>> internal compiler error: tree check: expected record_type or union_type
>> or qual_union_type, have function_type in gfc_class_len_get, at
>> fortran/trans-expr.cc:271
>> 0x19fd5d5 tree_check_failed(tree_node const*, char const*, int, char
>> const*, ...)
>>           ../../gcc-trunk/gcc/tree.cc:8952
>> 0xe1562d tree_check3(tree_node*, char const*, int, char const*,
>> tree_code, tree_code, tree_code)
>>           ../../gcc-trunk/gcc/tree.h:3652
>> 0xe3e264 gfc_class_len_get(tree_node*)
>>           ../../gcc-trunk/gcc/fortran/trans-expr.cc:271
>> 0xecda48 trans_associate_var
>>           ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2325
>> 0xecdd09 gfc_trans_block_construct(gfc_code*)
>>           ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2383
>> [...]
>>
>> I don't see anything wrong with it: NAG groks it, like Nvidia and Flang,
>> while Intel crashes at runtime.
>>
>> Can you have another brief look?
>>
>> Thanks,
>> Harald
>>
>>
>> On 1/6/24 18:26, Paul Richard Thomas wrote:
>>> These PRs come about because of gfortran's single pass parsing. If the
>>> function in the title is parsed after the associate construct, then its
>>> type and rank are not known. The point at which this becomes a problem is
>>> when expressions within the associate block are parsed. primary.cc
>>> (gfc_match_varspec) could already deal with intrinsic types and so
>>> component references were the trigger for the problem.
>>>
>>> The two major parts of this patch are the fixup needed in
>> gfc_match_varspec
>>> and the resolution of  expressions with references in resolve.cc
>>> (gfc_fixup_inferred_type_refs). The former relies on the two new
>> functions
>>> in symbol.cc to search for derived types with an appropriate component to
>>> match the component reference and then set the associate name to have a
>>> matching derived type. gfc_fixup_inferred_type_refs is called in
>> resolution
>>> and so the type of the selector function is known.
>>> gfc_fixup_inferred_type_refs ensures that the component references use
>> this
>>> derived type and that array references occur in the right place in
>>> expressions and match preceding array specs. Most of the work in
>> preparing
>>> the patch was sorting out cases where the selector was not a derived type
>>> but, instead, a class function. If it were not for this, the patch would
>>> have been submitted six months ago :-(
>>>
>>> The patch is relatively safe because most of the chunks are guarded by
>>> testing for the associate name being an inferred type, which is set in
>>> gfc_match_varspec. For this reason, I do not think it likely that the
>> patch
>>> will cause regressions. However, it is more than possible that variants
>> not
>>> appearing in the submitted testcase will throw up new bugs.
>>>
>>> Jerry has already given the patch a whirl and found that it applies
>>> cleanly, regtests OK and works as advertised.
>>>
>>> OK for trunk?
>>>
>>> Paul
>> ...snip...
>
  

Patch

diff --git a/gcc/fortran/class.cc b/gcc/fortran/class.cc
index 5c43b77dba3..7db1ecbd264 100644
--- a/gcc/fortran/class.cc
+++ b/gcc/fortran/class.cc
@@ -815,6 +815,56 @@  gfc_build_class_symbol (gfc_typespec *ts, symbol_attribute *attr,
 }
 
 
+/* Change class, using gfc_build_class_symbol. This is needed for associate
+   names, when rank changes or a derived type is produced by resolution.  */
+
+void
+gfc_change_class (gfc_typespec *ts, symbol_attribute *sym_attr,
+		  gfc_array_spec *sym_as, int rank, int corank)
+{
+  symbol_attribute attr;
+  gfc_component *c;
+  gfc_array_spec *as = NULL;
+  gfc_symbol *der = ts->u.derived;
+
+  ts->type = BT_CLASS;
+  attr = *sym_attr;
+  attr.class_ok = 0;
+  attr.associate_var = 1;
+  attr.class_pointer = 1;
+  attr.allocatable = 0;
+  attr.pointer = 1;
+  attr.dimension = rank ? 1 : 0;
+  if (rank)
+    {
+      if (sym_as)
+	as = gfc_copy_array_spec (sym_as);
+      else
+	{
+	  as = gfc_get_array_spec ();
+	  as->rank = rank;
+	  as->type = AS_DEFERRED;
+	  as->corank = corank;
+	}
+    }
+  if (as && as->corank != 0)
+    attr.codimension = 1;
+
+  if (!gfc_build_class_symbol (ts, &attr, &as))
+    gcc_unreachable ();
+
+  gfc_set_sym_referenced (ts->u.derived);
+
+  /* Make sure the _vptr is set.  */
+  c = gfc_find_component (ts->u.derived, "_vptr", true, true, NULL);
+  if (c->ts.u.derived == NULL)
+    c->ts.u.derived = gfc_find_derived_vtab (der);
+  /* _vptr now has the _vtab in it, change it to the _vtype.  */
+  if (c->ts.u.derived->attr.vtab)
+    c->ts.u.derived = c->ts.u.derived->ts.u.derived;
+}
+
+
 /* Add a procedure pointer component to the vtype
    to represent a specific type-bound procedure.  */
 
diff --git a/gcc/fortran/dump-parse-tree.cc b/gcc/fortran/dump-parse-tree.cc
index ecf71036444..a233f9f1110 100644
--- a/gcc/fortran/dump-parse-tree.cc
+++ b/gcc/fortran/dump-parse-tree.cc
@@ -2690,11 +2690,20 @@  show_code_node (int level, gfc_code *c)
 
     case EXEC_BLOCK:
       {
-	const char* blocktype;
+	const char *blocktype, *sname = NULL;
 	gfc_namespace *saved_ns;
 	gfc_association_list *alist;
 
-	if (c->ext.block.assoc)
+	if (c->ext.block.ns && c->ext.block.ns->code
+	    && c->ext.block.ns->code->op == EXEC_SELECT_TYPE)
+	  {
+	    gfc_expr *fcn = c->ext.block.ns->code->expr1;
+	    blocktype = "SELECT TYPE";
+	    /* expr1 is _loc(assoc_name->vptr)  */
+	    if (fcn && fcn->expr_type == EXPR_FUNCTION)
+	      sname = fcn->value.function.actual->expr->symtree->n.sym->name;
+	  }
+	else if (c->ext.block.assoc)
 	  blocktype = "ASSOCIATE";
 	else
 	  blocktype = "BLOCK";
@@ -2702,7 +2711,7 @@  show_code_node (int level, gfc_code *c)
 	fprintf (dumpfile, "%s ", blocktype);
 	for (alist = c->ext.block.assoc; alist; alist = alist->next)
 	  {
-	    fprintf (dumpfile, " %s = ", alist->name);
+	    fprintf (dumpfile, " %s = ", sname ? sname : alist->name);
 	    show_expr (alist->target);
 	  }
 
@@ -2733,7 +2742,7 @@  show_code_node (int level, gfc_code *c)
       if (c->op == EXEC_SELECT_RANK)
 	fputs ("SELECT RANK ", dumpfile);
       else if (c->op == EXEC_SELECT_TYPE)
-	fputs ("SELECT TYPE ", dumpfile);
+	fputs ("SELECT CASE ", dumpfile); // Preceded by SELECT TYPE construct
       else
 	fputs ("SELECT CASE ", dumpfile);
       show_expr (c->expr1);
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index b5e1b4c9d4b..13d5c5b2244 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -2963,6 +2963,11 @@  typedef struct gfc_association_list
   locus where;
 
   gfc_expr *target;
+
+  /* Used for inferring the derived type of an associate name, whose selector
+     is a sibling derived type function that has not yet been parsed.  */
+  gfc_symbol *derived_types;
+  unsigned inferred_type:1;
 }
 gfc_association_list;
 #define gfc_get_association_list() XCNEW (gfc_association_list)
@@ -3529,6 +3534,7 @@  bool gfc_add_component (gfc_symbol *, const char *, gfc_component **);
 gfc_symbol *gfc_use_derived (gfc_symbol *);
 gfc_component *gfc_find_component (gfc_symbol *, const char *, bool, bool,
                                    gfc_ref **);
+int gfc_find_derived_types (gfc_symbol *, gfc_namespace *, const char *);
 
 gfc_st_label *gfc_get_st_label (int);
 void gfc_free_st_label (gfc_st_label *);
@@ -3794,6 +3800,7 @@  void gfc_free_association_list (gfc_association_list *);
 void gfc_expression_rank (gfc_expr *);
 bool gfc_op_rank_conformable (gfc_expr *, gfc_expr *);
 bool gfc_resolve_ref (gfc_expr *);
+void gfc_fixup_inferred_type_refs (gfc_expr *);
 bool gfc_resolve_expr (gfc_expr *);
 void gfc_resolve (gfc_namespace *);
 void gfc_resolve_code (gfc_code *, gfc_namespace *);
@@ -3987,6 +3994,8 @@  unsigned int gfc_hash_value (gfc_symbol *);
 gfc_expr *gfc_get_len_component (gfc_expr *e, int);
 bool gfc_build_class_symbol (gfc_typespec *, symbol_attribute *,
 			     gfc_array_spec **);
+void gfc_change_class (gfc_typespec *, symbol_attribute *,
+		       gfc_array_spec *, int, int);
 gfc_symbol *gfc_find_derived_vtab (gfc_symbol *);
 gfc_symbol *gfc_find_vtab (gfc_typespec *);
 gfc_symtree* gfc_find_typebound_proc (gfc_symbol*, bool*,
@@ -4017,6 +4026,10 @@  bool gfc_may_be_finalized (gfc_typespec);
 #define IS_PROC_POINTER(sym) \
 	(sym->ts.type == BT_CLASS && sym->attr.class_ok && CLASS_DATA (sym) \
 	 ? CLASS_DATA (sym)->attr.proc_pointer : sym->attr.proc_pointer)
+#define IS_INFERRED_TYPE(expr) \
+	(expr && expr->expr_type == EXPR_VARIABLE \
+	 && expr->symtree->n.sym->assoc \
+	 && expr->symtree->n.sym->assoc->inferred_type)
 
 /* frontend-passes.cc */
 
diff --git a/gcc/fortran/match.cc b/gcc/fortran/match.cc
index df9adb359a0..6a523d5ab6e 100644
--- a/gcc/fortran/match.cc
+++ b/gcc/fortran/match.cc
@@ -6322,7 +6322,8 @@  gfc_match_select (void)
 /* Transfer the selector typespec to the associate name.  */
 
 static void
-copy_ts_from_selector_to_associate (gfc_expr *associate, gfc_expr *selector)
+copy_ts_from_selector_to_associate (gfc_expr *associate, gfc_expr *selector,
+				    bool select_type = false)
 {
   gfc_ref *ref;
   gfc_symbol *assoc_sym;
@@ -6405,12 +6406,30 @@  copy_ts_from_selector_to_associate (gfc_expr *associate, gfc_expr *selector)
     assoc_sym->as = NULL;
 
 build_class_sym:
-  if (selector->ts.type == BT_CLASS)
+  /* Deal with the very specific case of a SELECT_TYPE selector being an
+     associate_name whose type has been identified by component references.
+     It must be assumed that it will be identified as a CLASS expression,
+     so convert it now.  */
+  if (select_type
+      && IS_INFERRED_TYPE (selector)
+      && selector->ts.type == BT_DERIVED)
+    {
+      gfc_find_derived_vtab (selector->ts.u.derived);
+      /* The correct class container has to be available.  */
+      assoc_sym->ts.u.derived = selector->ts.u.derived;
+      assoc_sym->ts.type = BT_CLASS;
+      assoc_sym->attr.pointer = 1;
+      if (!selector->ts.u.derived->attr.is_class)
+	gfc_build_class_symbol (&assoc_sym->ts, &assoc_sym->attr, &assoc_sym->as);
+      associate->ts = assoc_sym->ts;
+    }
+  else if (selector->ts.type == BT_CLASS)
     {
       /* The correct class container has to be available.  */
       assoc_sym->ts.type = BT_CLASS;
       assoc_sym->ts.u.derived = CLASS_DATA (selector)
-	? CLASS_DATA (selector)->ts.u.derived : selector->ts.u.derived;
+				? CLASS_DATA (selector)->ts.u.derived
+				: selector->ts.u.derived;
       assoc_sym->attr.pointer = 1;
       gfc_build_class_symbol (&assoc_sym->ts, &assoc_sym->attr, &assoc_sym->as);
     }
@@ -6438,7 +6457,7 @@  build_associate_name (const char *name, gfc_expr **e1, gfc_expr **e2)
   if (expr2->ts.type == BT_UNKNOWN)
     sym->attr.untyped = 1;
   else
-    copy_ts_from_selector_to_associate (expr1, expr2);
+    copy_ts_from_selector_to_associate (expr1, expr2, true);
 
   sym->attr.flavor = FL_VARIABLE;
   sym->attr.referenced = 1;
diff --git a/gcc/fortran/parse.cc b/gcc/fortran/parse.cc
index 042a6ad5e59..8c7d269ab96 100644
--- a/gcc/fortran/parse.cc
+++ b/gcc/fortran/parse.cc
@@ -5149,6 +5149,17 @@  parse_associate (void)
       sym->declared_at = a->where;
       gfc_set_sym_referenced (sym);
 
+      /* If the selector is a inferred type then the associate_name had better
+	 be as well. Use array references, if present, to identify it as an
+	 array.  */
+      if (IS_INFERRED_TYPE (a->target))
+	{
+	  sym->assoc->inferred_type = 1;
+	  for (gfc_ref *r = a->target->ref; r; r = r->next)
+	    if (r->type == REF_ARRAY)
+	      sym->attr.dimension = 1;
+	}
+
       /* Initialize the typespec.  It is not available in all cases,
 	 however, as it may only be set on the target during resolution.
 	 Still, sometimes it helps to have it right now -- especially
@@ -5175,21 +5186,41 @@  parse_associate (void)
 	       && sym->ts.u.cl->length->expr_type == EXPR_CONSTANT))
 	sym->ts.u.cl = gfc_new_charlen (gfc_current_ns, NULL);
 
+      /* If the function has been parsed, go straight to the result to
+	 obtain the expression rank.  */
+      if (target->expr_type == EXPR_FUNCTION
+	  && target->symtree
+	  && target->symtree->n.sym)
+	{
+	  tsym = target->symtree->n.sym;
+	  if (!tsym->result)
+	    tsym->result = tsym;
+	  sym->ts = tsym->result->ts;
+	  if (sym->ts.type == BT_CLASS)
+	    {
+	      if (CLASS_DATA (sym)->as)
+		target->rank = CLASS_DATA (sym)->as->rank;
+	      sym->attr.class_ok = 1;
+	    }
+	  else
+	    target->rank = tsym->result->as ? tsym->result->as->rank : 0;
+	}
+
       /* Check if the target expression is array valued. This cannot be done
 	 by calling gfc_resolve_expr because the context is unavailable.
 	 However, the references can be resolved and the rank of the target
 	 expression set.  */
-      if (target->ref && gfc_resolve_ref (target)
+      if (!sym->assoc->inferred_type
+	  && target->ref && gfc_resolve_ref (target)
 	  && target->expr_type != EXPR_ARRAY
 	  && target->expr_type != EXPR_COMPCALL)
 	gfc_expression_rank (target);
 
       /* Determine whether or not function expressions with unknown type are
 	 structure constructors. If so, the function result can be converted
-	 to be a derived type.
-	 TODO: Deal with references to sibling functions that have not yet been
-	 parsed (PRs 89645 and 99065).  */
-      if (target->expr_type == EXPR_FUNCTION && target->ts.type == BT_UNKNOWN)
+	 to be a derived type.  */
+      if (target->expr_type == EXPR_FUNCTION
+	  && target->ts.type == BT_UNKNOWN)
 	{
 	  gfc_symbol *derived;
 	  /* The derived type has a leading uppercase character.  */
@@ -5199,16 +5230,7 @@  parse_associate (void)
 	    {
 	      sym->ts.type = BT_DERIVED;
 	      sym->ts.u.derived = derived;
-	    }
-	  else if (target->symtree && (tsym = target->symtree->n.sym))
-	    {
-	      sym->ts = tsym->result ? tsym->result->ts : tsym->ts;
-	      if (sym->ts.type == BT_CLASS)
-		{
-		  if (CLASS_DATA (sym)->as)
-		    target->rank = CLASS_DATA (sym)->as->rank;
-		  sym->attr.class_ok = 1;
-		}
+	      sym->assoc->inferred_type = 0;
 	    }
 	}
 
diff --git a/gcc/fortran/primary.cc b/gcc/fortran/primary.cc
index f8a1c09d190..17710b1f99d 100644
--- a/gcc/fortran/primary.cc
+++ b/gcc/fortran/primary.cc
@@ -2057,6 +2057,7 @@  gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
   bool unknown;
   bool inquiry;
   bool intrinsic;
+  bool inferred_type;
   locus old_loc;
   char sep;
 
@@ -2087,6 +2088,18 @@  gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
   if (sym->assoc && sym->assoc->target)
     tgt_expr = sym->assoc->target;
 
+  inferred_type = IS_INFERRED_TYPE (primary);
+
+  /* SELECT TYPE and SELECT RANK temporaries within an ASSOCIATE block, whose
+     selector has not been parsed, can generate errors with array and component
+     refs.. Use 'inferred_type' as a flag to suppress these errors.  */
+  if (!inferred_type
+      && (gfc_peek_ascii_char () == '(' && !sym->attr.dimension)
+      && !sym->attr.codimension
+      && sym->attr.select_type_temporary
+      && !sym->attr.select_rank_temporary)
+    inferred_type = true;
+
   /* For associate names, we may not yet know whether they are arrays or not.
      If the selector expression is unambiguously an array; eg. a full array
      or an array section, then the associate name must be an array and we can
@@ -2136,7 +2149,8 @@  gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
 	sym->ts.u.derived = tgt_expr->ts.u.derived;
     }
 
-  if ((equiv_flag && gfc_peek_ascii_char () == '(')
+  if ((inferred_type && !sym->as && gfc_peek_ascii_char () == '(')
+      || (equiv_flag && gfc_peek_ascii_char () == '(')
       || gfc_peek_ascii_char () == '[' || sym->attr.codimension
       || (sym->attr.dimension && sym->ts.type != BT_CLASS
 	  && !sym->attr.proc_pointer && !gfc_is_proc_ptr_comp (primary)
@@ -2194,7 +2208,7 @@  gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
   inquiry = false;
   if (m == MATCH_YES && sep == '%'
       && primary->ts.type != BT_CLASS
-      && primary->ts.type != BT_DERIVED)
+      && (primary->ts.type != BT_DERIVED || inferred_type))
     {
       match mm;
       old_loc = gfc_current_locus;
@@ -2209,7 +2223,8 @@  gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
     gfc_set_default_type (sym, 0, sym->ns);
 
   /* See if there is a usable typespec in the "no IMPLICIT type" error.  */
-  if (sym->ts.type == BT_UNKNOWN && m == MATCH_YES)
+  if ((sym->ts.type == BT_UNKNOWN || inferred_type)
+      && m == MATCH_YES)
     {
       bool permissible;
 
@@ -2228,9 +2243,34 @@  gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
 	  sym->ts = tgt_expr->ts;
 	}
 
+      /* If this hasn't done the trick and the target expression is a function,
+	 then this must be a derived type if 'name' matches an accessible type
+	 both in this namespace and the as yet unparsed sibling function.  */
+      if (tgt_expr && tgt_expr->expr_type == EXPR_FUNCTION
+	  && (sym->ts.type == BT_UNKNOWN || inferred_type)
+	  && gfc_find_derived_types (sym, gfc_current_ns, name))
+	{
+	  sym->assoc->inferred_type = 1;
+	  /* The first returned type is as good as any at this stage.  */
+	  gfc_symbol **dts = &sym->assoc->derived_types;
+	  tgt_expr->ts.type = BT_DERIVED;
+	  tgt_expr->ts.kind = 0;
+	  tgt_expr->ts.u.derived = *dts;
+	  sym->ts = tgt_expr->ts;
+	  /* Delete the dt list to prevent interference with trans-type.cc's
+	     treatment of derived type decls, even if this process has to be
+	     done again for another primary expression.  */
+	  while (*dts && (*dts)->dt_next)
+	    {
+	      gfc_symbol **tmp = &(*dts)->dt_next;
+	      *dts = NULL;
+	      dts = tmp;
+	    }
+	}
+
       if (sym->ts.type == BT_UNKNOWN)
 	{
-	  gfc_error ("Symbol %qs at %C has no IMPLICIT type", sym->name);
+	  gfc_error ("Symbol %qs at %C has no IMPLICIT type(primary)", sym->name);
 	  return MATCH_ERROR;
 	}
     }
diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index 2925f7da28c..dcf8750ba97 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -5866,6 +5866,13 @@  resolve_variable (gfc_expr *e)
       return false;
     }
 
+  /* Guessed type variables are associate_names whose selector had not been
+     parsed at the time that the construct was parsed. Now the namespace is
+     being resolved, the TKR of the selector will be available for fixup of
+     the associate_name.  */
+  if (IS_INFERRED_TYPE (e) && e->ref)
+    gfc_fixup_inferred_type_refs (e);
+
   /* For variables that are used in an associate (target => object) where
      the object's basetype is array valued while the target is scalar,
      the ts' type of the component refs is still array valued, which
@@ -6171,6 +6178,124 @@  resolve_procedure:
 }
 
 
+/* 'sym' was initially guessed to be derived type but has been corrected
+   in resolve_assoc_var to be a class entity or the derived type correcting.
+   If a class entity it will certainly need the _data reference or the
+   reference derived type symbol correcting in the first component ref if
+   a derived type.  */
+
+void
+gfc_fixup_inferred_type_refs (gfc_expr *e)
+{
+  gfc_ref *ref;
+  gfc_symbol *sym, *derived;
+
+  sym = e->symtree->n.sym;
+
+  /* This is an associate_name whose selector is a component ref of a selector
+     that is a inferred type associate_name.  */
+  if (sym->ts.type != BT_DERIVED && sym->ts.type != BT_CLASS)
+    {
+      e->rank = sym->as ? sym->as->rank : 0;
+      sym->attr.dimension = e->rank ? 1 : 0;
+      if (!e->rank && e->ref->type == REF_ARRAY)
+	{
+	  ref = e->ref;
+	  e->ref = ref->next;
+	  free (ref);
+	}
+      return;
+    }
+
+  derived = sym->ts.type == BT_CLASS ? CLASS_DATA (sym)->ts.u.derived
+				     : sym->ts.u.derived;
+
+  /* Ensure that class symbols have an array spec and ensure that there
+     is a _data field reference following class type references.  */
+  if (sym->ts.type == BT_CLASS
+      && sym->assoc->target->ts.type == BT_CLASS)
+    {
+      e->rank = CLASS_DATA (sym)->as ? CLASS_DATA (sym)->as->rank : 0;
+      sym->attr.dimension = 0;
+      CLASS_DATA (sym)->attr.dimension = e->rank ? 1 : 0;
+      if (e->ref && (e->ref->type != REF_COMPONENT
+		     || e->ref->u.c.component->name[0] != '_'))
+	{
+	  ref = gfc_get_ref ();
+	  ref->type = REF_COMPONENT;
+	  ref->next = e->ref;
+	  e->ref = ref;
+	  ref->u.c.component = gfc_find_component (sym->ts.u.derived, "_data",
+						   true, true, NULL);
+	  ref->u.c.sym = sym->ts.u.derived;
+	}
+    }
+
+  /* Proceed as far as the first component reference and ensure that the
+     correct derived type is being used.  */
+  for (ref = e->ref; ref; ref = ref->next)
+    if (ref->type == REF_COMPONENT)
+      {
+	if (ref->u.c.component->name[0] != '_')
+	  ref->u.c.sym = derived;
+	else
+	  ref->u.c.sym = sym->ts.u.derived;
+	break;
+      }
+
+  gfc_expr *target = sym->assoc->target;
+  if (sym->ts.type == BT_CLASS
+      && IS_INFERRED_TYPE (target)
+      && target->ts.type == BT_DERIVED
+      && CLASS_DATA (sym)->ts.u.derived == target->ts.u.derived
+      && target->ref && target->ref->next
+      && target->ref->next->type == REF_ARRAY)
+    target->ts = target->symtree->n.sym->ts;
+
+  /* Verify that the type inferrence mechanism has not introduced a spurious
+     array reference.  This can happen with an associate name, whose selector
+     is an element of another inferred type.  */
+  if (!(sym->ts.type == BT_CLASS ? CLASS_DATA (sym)->as : sym->as)
+      && e != e->symtree->n.sym->assoc->target
+      && !e->symtree->n.sym->assoc->target->rank)
+    {
+      /* First case: array ref after the scalar class or derived associate_name.  */
+      if (e->ref && e->ref->type == REF_ARRAY
+	  && e->ref->u.ar.type != AR_ELEMENT)
+	{
+	  ref = e->ref;
+	  e->ref = ref->next;
+	  free (ref);
+
+	  /* If it hasn't a ref to the '_data' field supply one.  */
+	  if (sym->ts.type == BT_CLASS
+	      && !(e->ref->type == REF_COMPONENT
+		   && strcmp (e->ref->u.c.component->name, "_data")))
+	    {
+	      gfc_ref *new_ref;
+	      gfc_find_component (e->symtree->n.sym->ts.u.derived,
+				  "_data", true, true, &new_ref);
+	      new_ref->next = e->ref;
+	      e->ref = new_ref;
+	    }
+	}
+      /* 2nd case: a ref to the '_data' field followed by an array ref.  */
+      else if (e->ref && e->ref->type == REF_COMPONENT
+	       && strcmp (e->ref->u.c.component->name, "_data") == 0
+	       && e->ref->next && e->ref->next->type == REF_ARRAY
+	       && e->ref->next->u.ar.type != AR_ELEMENT)
+	{
+	  ref = e->ref->next;
+	  e->ref->next = e->ref->next->next;
+	  free (ref);
+	}
+    }
+
+  /* Now that all the references are OK, get the expression rank.  */
+  gfc_expression_rank (e);
+}
+
+
 /* Checks to see that the correct symbol has been host associated.
    The only situations where this arises are:
 	(i)  That in which a twice contained function is parsed after
@@ -9263,6 +9388,46 @@  resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
       return;
     }
 
+  if (sym->assoc->inferred_type || IS_INFERRED_TYPE (target))
+    {
+      symbol_attribute attr;
+
+      /* By now, the type of the target has been fixed up.  */
+      if (sym->ts.type == BT_DERIVED
+	  && target->ts.type == BT_CLASS
+	  && !UNLIMITED_POLY (target))
+	{
+	  sym->ts = CLASS_DATA (target)->ts;
+	  if (!sym->as)
+	    sym->as = gfc_copy_array_spec (CLASS_DATA (target)->as);
+	  attr = CLASS_DATA (sym) ? CLASS_DATA (sym)->attr : sym->attr;
+	  sym->attr.dimension = target->rank ? 1 : 0;
+	  gfc_change_class (&sym->ts, &attr, sym->as,
+			    target->rank, gfc_get_corank (target));
+	  sym->as = NULL;
+	}
+      else if (target->ts.type == BT_DERIVED
+	       && target->symtree->n.sym->ts.type == BT_CLASS
+	       && IS_INFERRED_TYPE (target)
+	       && target->ref && target->ref->next
+	       && target->ref->next->type == REF_ARRAY
+	       && !target->ref->next->next)
+	{
+	  sym->ts = target->ts;
+	  attr = CLASS_DATA (sym) ? CLASS_DATA (sym)->attr : sym->attr;
+	  sym->attr.dimension = target->rank ? 1 : 0;
+	  gfc_change_class (&sym->ts, &attr, sym->as,
+			    target->rank, gfc_get_corank (target));
+	  sym->as = NULL;
+	  target->ts = sym->ts;
+	}
+      else if ((target->ts.type == BT_DERIVED)
+	       || (sym->ts.type == BT_CLASS && target->ts.type == BT_CLASS
+		   && CLASS_DATA (target)->as && !CLASS_DATA (sym)->as))
+	sym->ts = target->ts;
+    }
+
+
   if (target->expr_type == EXPR_NULL)
     {
       gfc_error ("Selector at %L cannot be NULL()", &target->where);
@@ -9289,15 +9454,50 @@  resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 			  || gfc_is_ptr_fcn (target));
 
   /* Finally resolve if this is an array or not.  */
+  if (target->expr_type == EXPR_FUNCTION
+      && (sym->ts.type == BT_CLASS || sym->ts.type == BT_DERIVED))
+    {
+      gfc_expression_rank (target);
+      if (target->ts.type == BT_DERIVED
+	  && !sym->as
+	  && target->symtree->n.sym->as)
+	{
+	  sym->as = gfc_copy_array_spec (target->symtree->n.sym->as);
+	  sym->attr.dimension = 1;
+	}
+      else if (target->ts.type == BT_CLASS
+	       && CLASS_DATA (target)->as)
+	{
+	  target->rank = CLASS_DATA (target)->as->rank;
+	  if (!(sym->ts.type == BT_CLASS && CLASS_DATA (sym)->as))
+	    {
+	      sym->ts = target->ts;
+	      sym->attr.dimension = 0;
+	    }
+	}
+    }
+
+
   if (sym->attr.dimension && target->rank == 0)
     {
       /* primary.cc makes the assumption that a reference to an associate
 	 name followed by a left parenthesis is an array reference.  */
-      if (sym->ts.type != BT_CHARACTER)
-	gfc_error ("Associate-name %qs at %L is used as array",
-		   sym->name, &sym->declared_at);
-      sym->attr.dimension = 0;
-      return;
+      if (sym->assoc->inferred_type && sym->ts.type != BT_CLASS)
+	{
+	  gfc_expression_rank (sym->assoc->target);
+	  sym->attr.dimension = sym->assoc->target->rank ? 1 : 0;
+	  if (!sym->attr.dimension && sym->as)
+	    sym->as = NULL;
+	}
+
+      if (sym->attr.dimension && target->rank == 0)
+	{
+	  if (sym->ts.type != BT_CHARACTER)
+	    gfc_error ("Associate-name %qs at %L is used as array",
+		       sym->name, &sym->declared_at);
+	  sym->attr.dimension = 0;
+	  return;
+	}
     }
 
   /* We cannot deal with class selectors that need temporaries.  */
@@ -9356,7 +9556,7 @@  resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 	     correct this now.  */
 	  gfc_typespec *ts = &target->ts;
 	  gfc_ref *ref;
-	  gfc_component *c;
+
 	  for (ref = target->ref; ref != NULL; ref = ref->next)
 	    {
 	      switch (ref->type)
@@ -9374,32 +9574,15 @@  resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 	    }
 	  /* Create a scalar instance of the current class type.  Because the
 	     rank of a class array goes into its name, the type has to be
-	     rebuild.  The alternative of (re-)setting just the attributes
+	     rebuilt.  The alternative of (re-)setting just the attributes
 	     and as in the current type, destroys the type also in other
 	     places.  */
 	  as = NULL;
 	  sym->ts = *ts;
 	  sym->ts.type = BT_CLASS;
 	  attr = CLASS_DATA (sym) ? CLASS_DATA (sym)->attr : sym->attr;
-	  attr.class_ok = 0;
-	  attr.associate_var = 1;
-	  attr.dimension = attr.codimension = 0;
-	  attr.class_pointer = 1;
-	  if (!gfc_build_class_symbol (&sym->ts, &attr, &as))
-	    gcc_unreachable ();
-	  /* Make sure the _vptr is set.  */
-	  c = gfc_find_component (sym->ts.u.derived, "_vptr", true, true, NULL);
-	  if (c->ts.u.derived == NULL)
-	    c->ts.u.derived = gfc_find_derived_vtab (sym->ts.u.derived);
-	  CLASS_DATA (sym)->attr.pointer = 1;
-	  CLASS_DATA (sym)->attr.class_pointer = 1;
-	  gfc_set_sym_referenced (sym->ts.u.derived);
-	  gfc_commit_symbol (sym->ts.u.derived);
-	  /* _vptr now has the _vtab in it, change it to the _vtype.  */
-	  if (c->ts.u.derived->attr.vtab)
-	    c->ts.u.derived = c->ts.u.derived->ts.u.derived;
-	  c->ts.u.derived->ns->types_resolved = 0;
-	  resolve_types (c->ts.u.derived->ns);
+	  gfc_change_class (&sym->ts, &attr, as, 0, 0);
+	  sym->as = NULL;
 	}
     }
 
@@ -9443,6 +9626,14 @@  resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 	}
     }
 
+  if (sym->ts.type == BT_CLASS
+      && IS_INFERRED_TYPE (target)
+      && target->ts.type == BT_DERIVED
+      && CLASS_DATA (sym)->ts.u.derived == target->ts.u.derived
+      && target->ref && target->ref->next
+      && target->ref->next->type == REF_ARRAY)
+    target->ts = target->symtree->n.sym->ts;
+
   /* If the target is a good class object, so is the associate variable.  */
   if (sym->ts.type == BT_CLASS && gfc_expr_attr (target).class_ok)
     sym->attr.class_ok = 1;
diff --git a/gcc/fortran/symbol.cc b/gcc/fortran/symbol.cc
index a6078bc608a..f66831df15f 100644
--- a/gcc/fortran/symbol.cc
+++ b/gcc/fortran/symbol.cc
@@ -291,6 +291,19 @@  bool
 gfc_set_default_type (gfc_symbol *sym, int error_flag, gfc_namespace *ns)
 {
   gfc_typespec *ts;
+  gfc_expr *e;
+
+  /* Check to see if a function selector of unknown type can be resolved.  */
+  if (sym->assoc
+      && (e = sym->assoc->target)
+      && e->expr_type == EXPR_FUNCTION)
+    {
+      if (e->ts.type == BT_UNKNOWN)
+	gfc_resolve_expr (e);
+      sym->ts = e->ts;
+      if (sym->ts.type != BT_UNKNOWN)
+	return true;
+    }
 
   if (sym->ts.type != BT_UNKNOWN)
     gfc_internal_error ("gfc_set_default_type(): symbol already has a type");
@@ -307,7 +320,7 @@  gfc_set_default_type (gfc_symbol *sym, int error_flag, gfc_namespace *ns)
 		       "; did you mean %qs?",
 		       sym->name, &sym->declared_at, guessed);
 	  else
-	    gfc_error ("Symbol %qs at %L has no IMPLICIT type",
+	    gfc_error ("Symbol %qs at %L has no IMPLICIT type(symbol)",
 		       sym->name, &sym->declared_at);
 	  sym->attr.untyped = 1; /* Ensure we only give an error once.  */
 	}
@@ -2402,6 +2415,66 @@  bad:
 }
 
 
+/* Find all derived types in the uppermost namespace that have a component
+   a component called name and stash them in the assoc field of an
+   associate name variable.
+   This is used to infer the derived type of an associate name, whose selector
+   is a sibling derived type function that has not yet been parsed. Either
+   the derived type is use associated in both contained and sibling procedures
+   or it appears in the uppermost namespace.  */
+
+static int cts = 0;
+static void
+find_derived_types (gfc_symbol *sym, gfc_symtree *st, const char *name,
+		    bool contained)
+{
+  if (st->n.sym && st->n.sym->attr.flavor == FL_DERIVED
+      && !st->n.sym->attr.is_class
+      && ((contained && st->n.sym->attr.use_assoc) || !contained)
+      && gfc_find_component (st->n.sym, name, true, true, NULL))
+    {
+      /* Do the stashing.  */
+      cts++;
+      if (sym->assoc->derived_types)
+	st->n.sym->dt_next = sym->assoc->derived_types;
+      sym->assoc->derived_types = st->n.sym;
+    }
+
+  if (st->left)
+    find_derived_types (sym, st->left, name, contained);
+
+  if (st->right)
+    find_derived_types (sym, st->right, name, contained);
+}
+
+int
+gfc_find_derived_types (gfc_symbol *sym, gfc_namespace *ns, const char *name)
+{
+  gfc_namespace *encompassing = NULL;
+  gcc_assert (sym->assoc);
+
+  cts = 0;
+  while (ns->parent)
+    {
+      if (!ns->parent->parent && ns->proc_name
+	  && (ns->proc_name->attr.function || ns->proc_name->attr.subroutine))
+	encompassing = ns;
+      ns = ns->parent;
+    }
+
+  if (!ns->contained)
+    return cts;
+
+  /* Search the top level namespace first.  */
+  find_derived_types (sym, ns->sym_root, name, false);
+
+  /* Then the encompassing namespace.  */
+  if (encompassing)
+    find_derived_types (sym, encompassing->sym_root, name, true);
+
+  return cts;
+}
+
 /* Find the component with the given name in the union type symbol.
    If ref is not NULL it will be set to the chain of components through which
    the component can actually be accessed. This is necessary for unions because
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index f4185db5b7f..3dac9d990f0 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -3134,6 +3134,10 @@  gfc_conv_variable (gfc_se * se, gfc_expr * expr)
       gcc_assert (se->string_length);
     }
 
+  /* Some expressions leak through that haven't been fixed up.  */
+  if (IS_INFERRED_TYPE (expr) && expr->ref)
+    gfc_fixup_inferred_type_refs (expr);
+
   gfc_typespec *ts = &sym->ts;
   while (ref)
     {
diff --git a/gcc/fortran/trans-stmt.cc b/gcc/fortran/trans-stmt.cc
index 517b7aaa898..bf4f1876969 100644
--- a/gcc/fortran/trans-stmt.cc
+++ b/gcc/fortran/trans-stmt.cc
@@ -1746,9 +1746,9 @@  trans_associate_var (gfc_symbol *sym, gfc_wrapped_block *block)
   e = sym->assoc->target;
 
   class_target = (e->expr_type == EXPR_VARIABLE)
-		    && e->ts.type == BT_CLASS
-		    && (gfc_is_class_scalar_expr (e)
-			|| gfc_is_class_array_ref (e, NULL));
+		  && e->ts.type == BT_CLASS
+		  && (gfc_is_class_scalar_expr (e)
+		      || gfc_is_class_array_ref (e, NULL));
 
   unlimited = UNLIMITED_POLY (e);
 
@@ -2156,26 +2156,36 @@  trans_associate_var (gfc_symbol *sym, gfc_wrapped_block *block)
 	    {
 	      tree stmp;
 	      tree dtmp;
+	      tree ctmp;
 
-	      se.expr = ctree;
+	      ctmp = ctree;
 	      dtmp = TREE_TYPE (TREE_TYPE (sym->backend_decl));
 	      ctree = gfc_create_var (dtmp, "class");
 
-	      stmp = gfc_class_data_get (se.expr);
+	      if (IS_INFERRED_TYPE (e)
+		  && !GFC_CLASS_TYPE_P (TREE_TYPE (se.expr)))
+		stmp = se.expr;
+	      else
+		stmp = gfc_class_data_get (ctmp);
+
 	      /* Coarray scalar component expressions can emerge from
 		 the front end as array elements of the _data field.  */
 	      if (GFC_DESCRIPTOR_TYPE_P (TREE_TYPE (stmp)))
 		stmp = gfc_conv_descriptor_data_get (stmp);
+
+	      if (!POINTER_TYPE_P (TREE_TYPE (stmp)))
+		stmp = gfc_build_addr_expr (NULL, stmp);
+
 	      dtmp = gfc_class_data_get (ctree);
 	      stmp = fold_convert (TREE_TYPE (dtmp), stmp);
 	      gfc_add_modify (&se.pre, dtmp, stmp);
-	      stmp = gfc_class_vptr_get (se.expr);
+	      stmp = gfc_class_vptr_get (ctmp);
 	      dtmp = gfc_class_vptr_get (ctree);
 	      stmp = fold_convert (TREE_TYPE (dtmp), stmp);
 	      gfc_add_modify (&se.pre, dtmp, stmp);
 	      if (UNLIMITED_POLY (sym))
 		{
-		  stmp = gfc_class_len_get (se.expr);
+		  stmp = gfc_class_len_get (ctmp);
 		  dtmp = gfc_class_len_get (ctree);
 		  stmp = fold_convert (TREE_TYPE (dtmp), stmp);
 		  gfc_add_modify (&se.pre, dtmp, stmp);