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/* Oort
* Copyright 2007, Soren Sandmann Pedersen
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* Check that variables are initialized before they are used.
*/
#include "ast.h"
static void
compute_initialized (node_t *node, gpointer data)
{
gboolean *changed = data;
set_t *tmp;
GList *list, *free_me;
list = free_me = node_list_predecessors (node);
if (!list)
tmp = set_new();
else
tmp = set_new_full();
while (list)
{
node_t *pred = list->data;
if (pred->common.init_vars)
set_intersect (tmp, pred->common.init_vars);
list = list->next;
}
g_list_free (free_me);
if (node->common.type == NODE_STORE)
set_add (tmp, node->store.definition);
if (node->common.type == NODE_INIT)
set_add (tmp, node->initialize.definition);
if (!node->common.init_vars)
{
node->common.init_vars = tmp;
*changed = TRUE;
}
else if (!set_equal (node->common.init_vars, tmp))
{
set_free (node->common.init_vars);
node->common.init_vars = tmp;
*changed = TRUE;
}
else
{
set_free (tmp);
}
}
gboolean
init_check (ast_t *ast)
{
gboolean changed;
node_t **nodes;
int i;
do
{
changed = FALSE;
node_breadth_first (ast->program.enter, compute_initialized, &changed);
}
while (changed);
nodes = node_list_all (ast->program.enter);
for (i = 0; nodes[i] != NULL; ++i)
{
node_t *node = nodes[i];
if (node->common.type == NODE_LOAD)
{
ast_variable_definition_t *definition = node->load.definition;
if (!set_contains (node->common.init_vars, definition) &&
!definition->field)
{
return report_error ("Uninitialized variable %s\n",
definition->name);
}
}
}
g_free (nodes);
return TRUE;
}
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