This patch fixes two issues:
a) It could happen that no code change has happened. In that case, the
one freed an expression which still should be used.
b) In my previous patch, I used a pointer assignment to the temporary of
the LHS (after its allocation) [only if the LHS was initially
unassigned]. That lead to a problem with double deallocation (temporary
+ LHS). In the previous test case, it didn't matter as the LHS wasn't
freed (implicit SAVE of in the main program). That's now solved by a
NULL-pointer assignment.
Finally, I corrected some indenting issues and removed unreachable code.
Build and regtested on x86-64-gnu-linux.
OK for the trunk and the 4.8 branch?
Tobias
PS: For the testcase of (a), I am not quite sure whether the intrinsic
assignment should invoke the defined assignment. It currently doesn't
for gfortran and crayftn. In any case, the invalid freeing is wrong.
2013-09-19 Tobias Burnus <bur...@net-b.de>
PR fortran/57697
PR fortran/58469
* resolve.c (generate_component_assignments): Avoid double free
at runtime and freeing a still-being used expr.
2013-09-19 Tobias Burnus <bur...@net-b.de>
PR fortran/57697
PR fortran/58469
* gfortran.dg/defined_assignment_8.f90: New.
* gfortran.dg/defined_assignment_9.f90: New.
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index d33fe49..4befb9fd 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -9602,8 +9602,9 @@ generate_component_assignments (gfc_code **code, gfc_namespace *ns)
&& gfc_expr_attr ((*code)->expr1).allocatable)
{
gfc_code *block;
- gfc_expr *cond;
- cond = gfc_get_expr ();
+ gfc_expr *cond;
+
+ cond = gfc_get_expr ();
cond->ts.type = BT_LOGICAL;
cond->ts.kind = gfc_default_logical_kind;
cond->expr_type = EXPR_OP;
@@ -9621,7 +9622,7 @@ generate_component_assignments (gfc_code **code, gfc_namespace *ns)
add_code_to_chain (&block, &head, &tail);
}
}
- }
+ }
else if (this_code->op == EXEC_ASSIGN && !this_code->next)
{
/* Don't add intrinsic assignments since they are already
@@ -9643,13 +9644,6 @@ generate_component_assignments (gfc_code **code, gfc_namespace *ns)
}
}
- /* This is probably not necessary. */
- if (this_code)
- {
- gfc_free_statements (this_code);
- this_code = NULL;
- }
-
/* Put the temporary assignments at the top of the generated code. */
if (tmp_head && component_assignment_level == 1)
{
@@ -9658,6 +9652,28 @@ generate_component_assignments (gfc_code **code, gfc_namespace *ns)
tmp_head = tmp_tail = NULL;
}
+ // If we did a pointer assignment - thus, we need to ensure that the LHS is
+ // not accidentally deallocated. Hence, nullify t1.
+ if (t1 && (*code)->expr1->symtree->n.sym->attr.allocatable
+ && gfc_expr_attr ((*code)->expr1).allocatable)
+ {
+ gfc_code *block;
+ gfc_expr *cond;
+ gfc_expr *e;
+
+ e = gfc_lval_expr_from_sym ((*code)->expr1->symtree->n.sym);
+ cond = gfc_build_intrinsic_call (ns, GFC_ISYM_ASSOCIATED, "associated",
+ (*code)->loc, 2, gfc_copy_expr (t1), e);
+ block = gfc_get_code (EXEC_IF);
+ block->block = gfc_get_code (EXEC_IF);
+ block->block->expr1 = cond;
+ block->block->next = build_assignment (EXEC_POINTER_ASSIGN,
+ t1, gfc_get_null_expr (&(*code)->loc),
+ NULL, NULL, (*code)->loc);
+ gfc_append_code (tail, block);
+ tail = block;
+ }
+
/* Now attach the remaining code chain to the input code. Step on
to the end of the new code since resolution is complete. */
gcc_assert ((*code)->op == EXEC_ASSIGN);
@@ -9667,7 +9683,8 @@ generate_component_assignments (gfc_code **code, gfc_namespace *ns)
gfc_free_expr ((*code)->expr1);
gfc_free_expr ((*code)->expr2);
**code = *head;
- free (head);
+ if (head != tail)
+ free (head);
*code = tail;
component_assignment_level--;
diff --git a/gcc/testsuite/gfortran.dg/defined_assignment_8.f90 b/gcc/testsuite/gfortran.dg/defined_assignment_8.f90
new file mode 100644
index 0000000..aab8085
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/defined_assignment_8.f90
@@ -0,0 +1,40 @@
+! { dg-do compile }
+!
+! PR fortran/58469
+!
+! Related: PR fortran/57697
+!
+! Was ICEing before
+!
+module m0
+ implicit none
+ type :: component
+ integer :: i = 42
+ contains
+ procedure :: assign0
+ generic :: assignment(=) => assign0
+ end type
+ type, extends(component) :: comp2
+ real :: aa
+ end type comp2
+ type parent
+ type(comp2) :: foo
+ end type
+contains
+ elemental subroutine assign0(lhs,rhs)
+ class(component), intent(INout) :: lhs
+ class(component), intent(in) :: rhs
+ lhs%i = 20
+ end subroutine
+end module
+
+program main
+ use m0
+ implicit none
+ type(parent), allocatable :: left
+ type(parent) :: right
+ print *, right%foo
+ left = right
+ print *, left%foo
+ if (left%foo%i /= 42) call abort()
+end
diff --git a/gcc/testsuite/gfortran.dg/defined_assignment_9.f90 b/gcc/testsuite/gfortran.dg/defined_assignment_9.f90
new file mode 100644
index 0000000..50fa007
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/defined_assignment_9.f90
@@ -0,0 +1,45 @@
+! { dg-do run }
+!
+! PR fortran/57697
+!
+! Further test of typebound defined assignment
+!
+module m0
+ implicit none
+ type component
+ integer :: i = 42
+ contains
+ procedure :: assign0
+ generic :: assignment(=) => assign0
+ end type
+ type parent
+ type(component) :: foo
+ end type
+contains
+ elemental subroutine assign0(lhs,rhs)
+ class(component), intent(INout) :: lhs
+ class(component), intent(in) :: rhs
+ lhs%i = 20
+ end subroutine
+end module
+
+program main
+ use m0
+ implicit none
+ block
+ type(parent), allocatable :: left
+ type(parent) :: right
+! print *, right%foo
+ left = right
+! print *, left%foo
+ if (left%foo%i /= 20) call abort()
+ end block
+ block
+ type(parent), allocatable :: left(:)
+ type(parent) :: right(5)
+! print *, right%foo
+ left = right
+! print *, left%foo
+ if (any (left%foo%i /= 20)) call abort()
+ end block
+end
