Patchwork [Fortran] PR 47775 - allocatable function RESULT and GENERIC

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Submitter Tobias Burnus
Date Feb. 18, 2011, 8:45 p.m.
Message ID <4D5EDA5B.4040306@net-b.de>
Download mbox | patch
Permalink /patch/83645/
State New
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Comments

Tobias Burnus - Feb. 18, 2011, 8:45 p.m.
For pointer and allocatable returning functions, a temporary needs to be 
used. This check did not work for generic procedures as the generic and 
the specific function was checked. Result: Wrong code, fortunately often 
"already allocated" error.

Build and regtested on x86-64-linux.
OK for the trunk? To which versions one should backport? Allocatable 
function results have been introduced in 4.2 ...

Tobias
Steve Kargl - Feb. 18, 2011, 9:25 p.m.
On Fri, Feb 18, 2011 at 09:45:15PM +0100, Tobias Burnus wrote:
> For pointer and allocatable returning functions, a temporary needs to be 
> used. This check did not work for generic procedures as the generic and 
> the specific function was checked. Result: Wrong code, fortunately often 
> "already allocated" error.
> 
> Build and regtested on x86-64-linux.
> OK for the trunk? To which versions one should backport? Allocatable 
> function results have been introduced in 4.2 ...
> 


OK with an update to the comment:

   /* Functions returning pointers need temporaries.  */

to include at least a mention of allocatables.

As to backporting, I think that neither 4.2 nor 4.3
branch will have another release, so only 4.4 and
4.5 seem appropriate.

Patch

2011-02-18  Tobias Burnus

	PR fortran/47775
	* trans-expr.c (arrayfunc_assign_needs_temporary): Use
	esym to check whether the specific procedure returns an
	allocatable or pointer.

2011-02-18  Tobias Burnus

	PR fortran/47775
	* gfortran.dg/func_result_6.f90: New.

diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index b7d7ed9..fe7f03c 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -5373,8 +5373,12 @@  arrayfunc_assign_needs_temporary (gfc_expr * expr1, gfc_expr * expr2)
     return true;
 
   /* Functions returning pointers need temporaries.  */
-  if (expr2->symtree->n.sym->attr.pointer 
-      || expr2->symtree->n.sym->attr.allocatable)
+  c = expr2->value.function.esym
+      ? (expr2->value.function.esym->attr.pointer 
+	 || expr2->value.function.esym->attr.allocatable)
+      : (expr2->symtree->n.sym->attr.pointer
+	 || expr2->symtree->n.sym->attr.allocatable);
+  if (c)
     return true;
 
   /* Character array functions need temporaries unless the
--- /dev/null	2011-02-18 07:54:09.295999992 +0100
+++ gcc/gcc/testsuite/gfortran.dg/func_result_6.f90	2011-02-18 14:07:14.000000000 +0100
@@ -0,0 +1,73 @@ 
+! { dg-do run }
+!
+! PR fortran/47775
+!
+! Contributed by Fran Martinez Fadrique
+!
+! Before, a temporary was missing for generic procedured (cf. test())
+! as the allocatable attribute was ignored for the check whether a
+! temporary is required
+!
+module m
+type t
+contains
+  procedure, NOPASS :: foo => foo
+  generic :: gen => foo
+end type t
+contains
+  function foo(i)
+    integer, allocatable :: foo(:)
+    integer :: i
+    allocate(foo(2))
+    foo(1) = i
+    foo(2) = i + 10
+  end function foo
+end module m
+
+use m
+type(t) :: x
+integer, pointer :: ptr1, ptr2
+integer, target              :: bar1(2)
+integer, target, allocatable :: bar2(:)
+
+allocate(bar2(2))
+ptr1 => bar1(2)
+ptr2 => bar2(2)
+
+bar1 = x%gen(1)
+if (ptr1 /= 11) call abort()
+bar1 = x%foo(2)
+if (ptr1 /= 12) call abort()
+bar2 = x%gen(3)
+if (ptr2 /= 13) call abort()
+bar2 = x%foo(4)
+if (ptr2 /= 14) call abort()
+bar2(:) = x%gen(5)
+if (ptr2 /= 15) call abort()
+bar2(:) = x%foo(6)
+if (ptr2 /= 16) call abort()
+
+call test()
+end
+
+subroutine test
+interface gen
+  procedure foo
+end interface gen
+
+integer, target :: bar(2)
+integer, pointer :: ptr
+bar = [1,2]
+ptr => bar(2)
+if (ptr /= 2) call abort()
+bar = gen()
+if (ptr /= 77) call abort()
+contains
+  function foo()
+    integer, allocatable :: foo(:)
+    allocate(foo(2))
+    foo = [33, 77]
+  end function foo
+end subroutine test
+
+! { dg-final { cleanup-modules "m" } }