diff --git a/ext/openssl/ossl_x509cert.c b/ext/openssl/ossl_x509cert.c
index 9f787d21..ab5d0d41 100644
--- a/ext/openssl/ossl_x509cert.c
+++ b/ext/openssl/ossl_x509cert.c
@@ -711,7 +711,7 @@ ossl_x509_eq(VALUE self, VALUE other)
 /*
  * call-seq:
  *    cert.tbs_bytes => string
- * 
+ *
  * Returns the DER-encoded bytes of the certificate's to be signed certificate.
  * This is mainly useful for validating embedded certificate transparency signatures.
  */
@@ -720,7 +720,7 @@ ossl_x509_tbs_bytes(VALUE self)
 {
     X509 *x509;
     int len;
-    unsigned char *p0, *p1;
+    unsigned char *p0;
     VALUE str;
 
     GetX509(self, x509);
@@ -729,7 +729,7 @@ ossl_x509_tbs_bytes(VALUE self)
         ossl_raise(eX509CertError, "i2d_re_X509_tbs");
     }
     str = rb_str_new(NULL, len);
-    p0 = p1 = (unsigned char *)RSTRING_PTR(str);
+    p0 = (unsigned char *)RSTRING_PTR(str);
     if (i2d_re_X509_tbs(x509, &p0) <= 0) {
         ossl_raise(eX509CertError, "i2d_re_X509_tbs");
     }