diff --git a/src/inc/def.h b/src/inc/def.h
index 7d98d98..90dc8ca 100644
--- a/src/inc/def.h
+++ b/src/inc/def.h
@@ -41,7 +41,6 @@
 #define int2compbase(seq)       "TGAC"[seq]
 #define int_comp(seq)   (char)(seq^0x02) //(char)((0x4E>>((seq)<<1))&0x03)
 
-int b_ban;
 
 #ifdef MER127
 typedef struct kmer
diff --git a/src/inc/extvab.h b/src/inc/extvab.h
index e71b5bb..f7fbe4c 100644
--- a/src/inc/extvab.h
+++ b/src/inc/extvab.h
@@ -119,5 +119,5 @@ extern int delowArc;
 extern int SupportNum;
 extern int N_kmer;//mao 2011-10-13
 extern int read_trace;//mao 2011-10-21
-Kmer kmerZero;
+extern Kmer kmerZero;
 
diff --git a/src/inc/global.h b/src/inc/global.h
index 919146c..a90bf58 100644
--- a/src/inc/global.h
+++ b/src/inc/global.h
@@ -115,13 +115,5 @@ int SupportNum=2;
 int N_kmer=0;//mao 2011-10-13
 int read_trace=0;//mao 2011-10-21
 
-#ifdef MER127
-Kmer kmerZero={0,0,0,0};
-#endif
-#ifdef MER63
-Kmer kmerZero={0,0};
-#endif
-#ifdef MER31
-Kmer kmerZero={0};
-#endif
+extern Kmer kmerZero;
 
diff --git a/src/main.c b/src/main.c
index 43e1f18..4863340 100644
--- a/src/main.c
+++ b/src/main.c
@@ -36,6 +36,16 @@ static void display_usage ();
 static void display_all_usage ();
 static void pipeline (int argc, char **argv);
 
+#ifdef MER127
+Kmer kmerZero={0,0,0,0};
+#endif
+#ifdef MER63
+Kmer kmerZero={0,0};
+#endif
+#ifdef MER31
+Kmer kmerZero={0};
+#endif
+
 int main (int argc, char **argv)
 {
 	printf ("\nVersion 1.04\n\n");