A bunch of dead assignments.

Caught by clang scan-build.

Change-Id: I4f10c879dc137d4a14a7a395764d28e5caa033ff
Reviewed-on: https://boringssl-review.googlesource.com/1342
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/bn/convert.c b/crypto/bn/convert.c
index 9befc49..048ac73 100644
--- a/crypto/bn/convert.c
+++ b/crypto/bn/convert.c
@@ -232,7 +232,6 @@
   BN_ULONG l=0;
 
   j = i; /* least significant 'hex' */
-  m = 0;
   h = 0;
   while (j > 0) {
     m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j;
@@ -383,7 +382,6 @@
       *p++ = '-';
     }
 
-    i = 0;
     while (!BN_is_zero(t)) {
       *lp = BN_div_word(t, BN_DEC_CONV);
       lp++;
diff --git a/crypto/bn/exponentiation.c b/crypto/bn/exponentiation.c
index 0c9d7a7..69c2f90 100644
--- a/crypto/bn/exponentiation.c
+++ b/crypto/bn/exponentiation.c
@@ -509,7 +509,6 @@
      * how bit a window to do.  To do this we need to scan
      * forward until the last set bit before the end of the
      * window */
-    j = wstart;
     wvalue = 1;
     wend = 0;
     for (i = 1; i < window; i++) {
diff --git a/crypto/des/des.c b/crypto/des/des.c
index ca87ee3..6d00011 100644
--- a/crypto/des/des.c
+++ b/crypto/des/des.c
@@ -413,7 +413,6 @@
   FP(r, l);
   data[0] = l;
   data[1] = r;
-  l = r = t = u = 0;
 }
 
 static void DES_encrypt2(uint32_t *data, const DES_key_schedule *ks, int enc) {
@@ -473,7 +472,6 @@
   /* rotate and clear the top bits on machines with 8byte longs */
   data[0] = ROTATE(l, 3) & 0xffffffffL;
   data[1] = ROTATE(r, 3) & 0xffffffffL;
-  l = r = t = u = 0;
 }
 
 static void DES_encrypt3(uint32_t *data, const DES_key_schedule *ks1,
@@ -532,7 +530,7 @@
   l2c(l, out);
   l = ll[1];
   l2c(l, out);
-  l = ll[0] = ll[1] = 0;
+  ll[0] = ll[1] = 0;
 }
 
 void DES_ncbc_encrypt(const uint8_t *in, uint8_t *out, size_t len,
@@ -608,7 +606,6 @@
     l2c(xor0, iv);
     l2c(xor1, iv);
   }
-  tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
   tin[0] = tin[1] = 0;
 }
 
@@ -709,6 +706,5 @@
     l2c(xor1, iv);
   }
 
-  tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
   tin[0] = tin[1] = 0;
 }
diff --git a/ssl/s3_clnt.c b/ssl/s3_clnt.c
index 13e3ae5..b61568a 100644
--- a/ssl/s3_clnt.c
+++ b/ssl/s3_clnt.c
@@ -2701,8 +2701,7 @@
 		{
 		/* If we get an error, we need to
 		 * ssl->rwstate=SSL_X509_LOOKUP; return(-1);
-		 * We then get retied later */
-		i=0;
+		 * We then get retried later */
 		i = ssl_do_client_cert_cb(s, &x509, &pkey);
 		if (i < 0)
 			{