Fix the next_block of the new block in ControlFlowGraph.split_block

Author: BergLucas

src/bytecode/cfg.py

@@ -710,6 +710,7 @@ def split_block(self, block: BasicBlock, index: int) -> BasicBlock:
         del block[index:]
 
         block2 = BasicBlock(instructions)
+        block2.next_block = block.next_block
         block.next_block = block2
 
         for block in self[block_index + 1 :]: