diff --git a/src/box/engine_sophia.cc b/src/box/engine_sophia.cc
index 71cb5e9823b73249136dc9c3029db82ec1473cfb..114e71c348cd8ec66cda0e3c57496bcd4e3d2c51 100644
--- a/src/box/engine_sophia.cc
+++ b/src/box/engine_sophia.cc
@@ -45,6 +45,8 @@
 #include <dirent.h>
 #include <errno.h>
 
+extern "C" void *sp_error(void *o, ...);
+
 struct Sophia: public Engine {
 	Sophia(EngineFactory*);
 };
diff --git a/src/box/sophia_index.cc b/src/box/sophia_index.cc
index c3b63ea8c83c104766e245ab210c8c9e3fe9ef87..2b62bda4704a937732cada220d8bfc82dbc61def 100644
--- a/src/box/sophia_index.cc
+++ b/src/box/sophia_index.cc
@@ -42,6 +42,8 @@
 #include <stdio.h>
 #include <inttypes.h>
 
+extern "C" void *sp_error(void *o, ...);
+
 static inline void
 sophia_delete(void *db, struct key_def *key_def, struct tuple *tuple)
 {