verify that start black has no predecessors

[r27814]

diff --git a/ir/ir/irvrfy.c b/ir/ir/irvrfy.c
index b9b28b0..fe56d2d 100644 (file)
--- a/ir/ir/irvrfy.c
+++ b/ir/ir/irvrfy.c
@@ -881,6 +881,10 @@ static int verify_node_Block(ir_node *n, ir_graph *irg)
                        "Block node must have a mode_X predecessor", 0);
        }
 
+       if (n == get_irg_start_block(irg)) {
+               ASSERT_AND_RET(get_Block_n_cfgpreds(n) == 0, "Start Block node", 0);
+       }
+
        if (n == get_irg_end_block(irg) && get_irg_phase_state(irg) != phase_backend)
                /* End block may only have Return, Raise or fragile ops as preds. */
                for (i = get_Block_n_cfgpreds(n) - 1; i >= 0; --i) {