diff --git a/afl_transforms/tools/zax/zax_base.cpp b/afl_transforms/tools/zax/zax_base.cpp
index 3466c79d0bdde198a9d6e7e066345fa755e9804c..a870430781f681aac71961e0f677c66895a925e7 100644
--- a/afl_transforms/tools/zax/zax_base.cpp
+++ b/afl_transforms/tools/zax/zax_base.cpp
@@ -431,6 +431,8 @@ void ZaxBase_t::setupForkServer()
 		}
 
 	}
+	getFileIR()->assembleRegistry();
+	getFileIR()->setBaseIDS();
 
 	// it's ok not to have a fork server at all, e.g. libraries
 }