diff --git a/global_structures.h b/global_structures.h
index 5f62cc2da..37be00cc0 100644
--- a/global_structures.h
+++ b/global_structures.h
@@ -180,6 +180,7 @@ struct FingerPrint {
   std::vector<OS_Classification> OS_class;
   std::vector<FingerTest> tests;
   const FingerTest *gettestbyname(const char *name) const;
+  FingerPrint();
 };
 
 /* This structure contains the important data from the fingerprint
diff --git a/osscan.cc b/osscan.cc
index a483ffba0..d0e50020b 100644
--- a/osscan.cc
+++ b/osscan.cc
@@ -188,6 +188,11 @@ FingerPrintDB::~FingerPrintDB() {
     delete *current;
 }
 
+FingerPrint::FingerPrint() {
+  line = 0;
+  OS_name = NULL;
+}
+
 const struct AVal *FingerTest::getattrbyname(const char *name) const {
   std::vector<struct AVal>::const_iterator i;