Change return back to break in the default case.
MODIFY
mrbgems/mruby-compiler/core/codegen.c
mrbgems/mruby-compiler/core/codegen.c
@@ -1026,7 +1026,7 @@ gen_assignment(codegen_scope *s, node *tree, int sp, int val)
#ifndef MRB_DISABLE_STDIO
fprintf(stderr, "unknown lhs %d\n", type);
#endif
- return;
+ break;
}
if (val) push();
}

Change return back to break in the default case.