diff --git a/crypto/evp/bio_b64.c b/crypto/evp/bio_b64.c
index ac6d441aa..16863fe23 100644
--- a/crypto/evp/bio_b64.c
+++ b/crypto/evp/bio_b64.c
@@ -226,6 +226,7 @@ static int b64_read(BIO *b, char *out, int outl)
 		else if (ctx->start)
 			{
 			q=p=(unsigned char *)ctx->tmp;
+			num = 0;
 			for (j=0; j<i; j++)
 				{
 				if (*(q++) != '\n') continue;