Include <cassert> where needed in generated code
diff --git a/gen/src/builtin.rs b/gen/src/builtin.rs
index 3b411aa..378467b 100644
--- a/gen/src/builtin.rs
+++ b/gen/src/builtin.rs
@@ -64,6 +64,7 @@
     if builtin.rust_vec {
         include.algorithm = true;
         include.array = true;
+        include.cassert = true;
         include.cstddef = true;
         include.cstdint = true;
         include.initializer_list = true;
@@ -78,6 +79,7 @@
 
     if builtin.rust_slice {
         include.array = true;
+        include.cassert = true;
         include.cstddef = true;
         include.cstdint = true;
         include.iterator = true;