353741: klocwork cascading memory leak in mpp_make_prime. r=nelson

security/nss/lib/freebl/mpi/mpprime.c

@@ -429,12 +429,12 @@ mp_err mpp_make_prime(mp_int *start, mp_size nBits, mp_size strong,
   mp_size       num_tests;
   unsigned char *sieve;
   
-  sieve = malloc(SIEVE_SIZE);
-  ARGCHK(sieve != NULL, MP_MEM);
-
   ARGCHK(start != 0, MP_BADARG);
   ARGCHK(nBits > 16, MP_RANGE);
 
+  sieve = malloc(SIEVE_SIZE);
+  ARGCHK(sieve != NULL, MP_MEM);
+
   MP_DIGITS(&trial) = 0;
   MP_DIGITS(&q) = 0;
   MP_CHECKOK( mp_init(&trial) );