Handle non-void functions which miss a return statement at the end. Especially handl...

[r18384]

diff --git a/ast2firm.c b/ast2firm.c
index 62793e5..ebe3957 100644 (file)
--- a/ast2firm.c
+++ b/ast2firm.c
@@ -1532,7 +1532,22 @@ static void create_function(declaration_t *declaration)
 
        /* do we have a return statement yet? */
        if(get_cur_block() != NULL) {
-               ir_node *ret = new_Return(get_store(), 0, NULL);
+               assert(declaration->type->type == TYPE_FUNCTION);
+               const function_type_t* const func_type = (const function_type_t*)declaration->type;
+               ir_node *ret;
+               if (func_type->result_type == type_void) {
+                       ret = new_Return(get_store(), 0, NULL);
+               } else {
+                       ir_mode *const mode = get_ir_mode(func_type->result_type);
+                       ir_node *      in[1];
+                       // §5.1.2.2.3 main implicitly returns 0
+                       if (strcmp(declaration->symbol->string, "main") == 0) {
+                               in[0] = new_Const(mode, get_mode_null(mode));
+                       } else {
+                               in[0] = new_Unknown(mode);
+                       }
+                       ret = new_Return(get_store(), 1, in);
+               }
                add_immBlock_pred(end_block, ret);
        }