diff --git a/src/aig/gia/giaDecGraph.cpp b/src/aig/gia/giaDecGraph.cpp
index 01a7101c6..0efbe7bf8 100644
--- a/src/aig/gia/giaDecGraph.cpp
+++ b/src/aig/gia/giaDecGraph.cpp
@@ -41,6 +41,7 @@
 
 #include "gia.h"
 #include "misc/vec/vecHash.h"
+#include "misc/extra/extra.h"
 
 ABC_NAMESPACE_IMPL_START
 
@@ -2180,10 +2181,6 @@ Gia_Man_t* Gia_ManDecGraph(Gia_Man_t* p) {
     return pNew;
 }
 
-extern "C" {
-extern char * Extra_FileReadContents( char * pFileName );
-}
-
 Gia_Man_t* Gia_ManDecGraphFromFile(char* pFileName) {
     char* pBuffer = Extra_FileReadContents(pFileName);