diff --git a/src/tactic/sls/sls_engine.h b/src/tactic/sls/sls_engine.h
index 5d4c9a0fc..96041d09e 100644
--- a/src/tactic/sls/sls_engine.h
+++ b/src/tactic/sls/sls_engine.h
@@ -22,6 +22,7 @@ Notes:
 #include"stopwatch.h"
 #include"lbool.h"
 #include"model_converter.h"
+#include"goal.h"
 
 #include"sls_compilation_settings.h"
 #include"sls_tracker.h"
diff --git a/src/tactic/sls/sls_tracker.h b/src/tactic/sls/sls_tracker.h
index f5c77fc35..50d0e4188 100644
--- a/src/tactic/sls/sls_tracker.h
+++ b/src/tactic/sls/sls_tracker.h
@@ -21,6 +21,7 @@ Notes:
 #define _SLS_TRACKER_H_
 
 #include"for_each_expr.h"
+#include"ast_smt2_pp.h"
 #include"bv_decl_plugin.h"
 #include"model.h"