@@ -9936,7 +9936,8 @@ trans_get_upoly_len (stmtblock_t *block, gfc_expr *expr)
static tree
trans_class_vptr_len_assignment (stmtblock_t *block, gfc_expr * le,
gfc_expr * re, gfc_se *rse,
- tree * to_lenp, tree * from_lenp)
+ tree * to_lenp, tree * from_lenp,
+ tree * from_vptrp)
{
gfc_se se;
gfc_expr * vptr_expr;
@@ -9944,10 +9945,11 @@ trans_class_vptr_len_assignment (stmtblock_t *block, gfc_expr * le,
bool set_vptr = false, temp_rhs = false;
stmtblock_t *pre = block;
tree class_expr = NULL_TREE;
+ tree from_vptr = NULL_TREE;
/* Create a temporary for complicated expressions. */
if (re->expr_type != EXPR_VARIABLE && re->expr_type != EXPR_NULL
- && rse->expr != NULL_TREE && !DECL_P (rse->expr))
+ && rse->expr != NULL_TREE)
{
if (re->ts.type == BT_CLASS && !GFC_CLASS_TYPE_P (TREE_TYPE (rse->expr)))
class_expr = gfc_get_class_from_expr (rse->expr);
@@ -10044,6 +10046,7 @@ trans_class_vptr_len_assignment (stmtblock_t *block, gfc_expr * le,
tmp = rse->expr;
se.expr = gfc_class_vptr_get (tmp);
+ from_vptr = se.expr;
if (UNLIMITED_POLY (re))
from_len = gfc_class_len_get (tmp);
@@ -10065,6 +10068,7 @@ trans_class_vptr_len_assignment (stmtblock_t *block, gfc_expr * le,
gfc_free_expr (vptr_expr);
gfc_add_block_to_block (block, &se.pre);
gcc_assert (se.post.head == NULL_TREE);
+ from_vptr = se.expr;
}
gfc_add_modify (pre, lhs_vptr, fold_convert (TREE_TYPE (lhs_vptr),
se.expr));
@@ -10093,11 +10097,13 @@ trans_class_vptr_len_assignment (stmtblock_t *block, gfc_expr * le,
}
}
- /* Return the _len trees only, when requested. */
+ /* Return the _len and _vptr trees only, when requested. */
if (to_lenp)
*to_lenp = to_len;
if (from_lenp)
*from_lenp = from_len;
+ if (from_vptrp)
+ *from_vptrp = from_vptr;
return lhs_vptr;
}
@@ -10166,7 +10172,7 @@ trans_class_pointer_fcn (stmtblock_t *block, gfc_se *lse, gfc_se *rse,
{
expr1_vptr = trans_class_vptr_len_assignment (block, expr1,
expr2, rse,
- NULL, NULL);
+ NULL, NULL, NULL);
gfc_add_block_to_block (block, &rse->pre);
tmp = gfc_create_var (TREE_TYPE (rse->expr), "ptrtemp");
gfc_add_modify (&lse->pre, tmp, rse->expr);
@@ -10242,7 +10248,7 @@ gfc_trans_pointer_assignment (gfc_expr * expr1, gfc_expr * expr2)
if (non_proc_ptr_assign && expr1->ts.type == BT_CLASS)
{
trans_class_vptr_len_assignment (&block, expr1, expr2, &rse, NULL,
- NULL);
+ NULL, NULL);
lse.expr = gfc_class_data_get (lse.expr);
}
@@ -10371,7 +10377,8 @@ gfc_trans_pointer_assignment (gfc_expr * expr1, gfc_expr * expr2)
if (expr1->ts.type == BT_CLASS)
expr1_vptr = trans_class_vptr_len_assignment (&block, expr1,
expr2, &rse,
- NULL, NULL);
+ NULL, NULL,
+ NULL);
}
}
else if (expr2->expr_type == EXPR_VARIABLE)
@@ -10388,7 +10395,7 @@ gfc_trans_pointer_assignment (gfc_expr * expr1, gfc_expr * expr2)
rse.expr = NULL_TREE;
rse.string_length = strlen_rhs;
trans_class_vptr_len_assignment (&block, expr1, expr2, &rse,
- NULL, NULL);
+ NULL, NULL, NULL);
}
if (remap == NULL)
@@ -10421,7 +10428,7 @@ gfc_trans_pointer_assignment (gfc_expr * expr1, gfc_expr * expr2)
{
expr1_vptr = trans_class_vptr_len_assignment (&block, expr1,
expr2, &rse, NULL,
- NULL);
+ NULL, NULL);
gfc_add_block_to_block (&block, &rse.pre);
tmp = gfc_create_var (TREE_TYPE (rse.expr), "ptrtemp");
gfc_add_modify (&lse.pre, tmp, rse.expr);
@@ -11819,7 +11826,7 @@ trans_class_assignment (stmtblock_t *block, gfc_expr *lhs, gfc_expr *rhs,
gfc_se *lse, gfc_se *rse, bool use_vptr_copy,
bool class_realloc)
{
- tree tmp, fcn, stdcopy, to_len, from_len, vptr, old_vptr;
+ tree tmp, fcn, stdcopy, to_len, from_len, vptr, old_vptr, rhs_vptr;
vec<tree, va_gc> *args = NULL;
bool final_expr;
@@ -11843,7 +11850,9 @@ trans_class_assignment (stmtblock_t *block, gfc_expr *lhs, gfc_expr *rhs,
}
vptr = trans_class_vptr_len_assignment (block, lhs, rhs, rse, &to_len,
- &from_len);
+ &from_len, &rhs_vptr);
+ if (rhs_vptr == NULL_TREE)
+ rhs_vptr = vptr;
/* Generate (re)allocation of the lhs. */
if (class_realloc)
@@ -11856,7 +11865,7 @@ trans_class_assignment (stmtblock_t *block, gfc_expr *lhs, gfc_expr *rhs,
else
old_vptr = build_int_cst (TREE_TYPE (vptr), 0);
- size = gfc_vptr_size_get (vptr);
+ size = gfc_vptr_size_get (rhs_vptr);
tmp = lse->expr;
class_han = GFC_CLASS_TYPE_P (TREE_TYPE (tmp))
? gfc_class_data_get (tmp) : tmp;
@@ -11875,7 +11884,7 @@ trans_class_assignment (stmtblock_t *block, gfc_expr *lhs, gfc_expr *rhs,
fold_convert (pvoid_type_node, class_han),
size);
tmp = fold_build2_loc (input_location, NE_EXPR,
- logical_type_node, vptr, old_vptr);
+ logical_type_node, rhs_vptr, old_vptr);
re = fold_build3_loc (input_location, COND_EXPR, void_type_node,
tmp, re, build_empty_stmt (input_location));
gfc_add_expr_to_block (&re_alloc, re);
new file mode 100644
@@ -0,0 +1,20 @@
+! { dg-do run }
+!
+! Contributed by Brad Richardson <everythingfunctional@protonmail.com>
+!
+ type, abstract :: p
+ end type p
+
+ type, extends(p) :: c
+ end type c
+
+ class(p), allocatable :: a
+
+ a = func()
+contains
+ function func() result(a)
+ class(p), allocatable :: a
+
+ a = c()
+ end function func
+end program
This patch adds the testcase from PR110415 and fixes the bug. The problem is that in a couple of places in trans_class_assignment in trans-expr.cc, we need to get the run-time size of the polymorphic object from the vtbl, but we are currently getting that vtbl from the lhs of the assignment rather than the rhs. This gives us the old value of the size but we need to pass the new size to __builtin_malloc and __builtin_realloc. I'm fixing this by adding a parameter to trans_class_vptr_len_assignment to retrieve the tree corresponding the vptr from the object on the rhs of the assignment, and then passing this where it is needed. In the case where trans_class_vptr_len_assignment returns NULL_TREE for the rhs vptr we use the lhs vptr as before. To get this to work I also needed to change the implementation of trans_class_vptr_len_assignment to create a temporary for the assignment in more circumstances. Currently, the "a = func()" assignment in MAIN__ doesn't hit the "Create a temporary for complication expressions" case on line 9951 because "DECL_P (rse->expr)" is true - the expression has already been placed into a temporary. That means we don't hit the "if (temp_rhs ..." case on line 10038 and go on to get the vptr_expr from "gfc_lval_expr_from_sym (gfc_find_vtab (&re->ts))" on line 10057 which is the vtbl of the static type rather than the dynamic one from the rhs. So with this fix we create an extra temporary, but that should be optimised away in the middle-end so there should be no run-time effect. I'm not sure if this is the best way to fix this (the Fortran front-end is new territory for me) but I've verified that the testcase passes with this change, fails without it, and that the change does not introduce any FAILs when running the gfortran testcases on x86_64-pc-linux-gnu. Is this OK for mainline, GCC 13 and OG13? Thanks, Andrew gcc/fortran/ * trans-expr.cc (trans_class_vptr_len_assignment): Add from_vptrp parameter. Populate it. Don't check for DECL_P when deciding whether to create temporary. (trans_class_pointer_fcn, gfc_trans_pointer_assignment): Add NULL argument to trans_class_vptr_len_assignment calls. (trans_class_assignment): Get rhs_vptr from trans_class_vptr_len_assignment and use it for determining size for allocation/reallocation. gcc/testsuite/ * gfortran.dg/pr110415.f90: New test.