Use uintptr_t instead of performing pointer subtraction with a null pointer

Signed-off-by: Qihao Chencao <twose@qq.com>

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/crypt/sha512-crypt.c b/crypt/sha512-crypt.c
index 9deb31ce99..b592eb0976 100644
--- a/crypt/sha512-crypt.c
+++ b/crypt/sha512-crypt.c
@@ -142,7 +142,7 @@ __sha512_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
   salt_len = MIN (strcspn (salt, "$"), SALT_LEN_MAX);
   key_len = strlen (key);
 
-  if ((key - (char *) 0) % __alignof__ (uint64_t) != 0)
+  if (((uintptr_t) key) % __alignof__ (uint64_t) != 0)
     {
       char *tmp;
 
@@ -157,19 +157,19 @@ __sha512_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
 
       key = copied_key =
 	memcpy (tmp + __alignof__ (uint64_t)
-		- (tmp - (char *) 0) % __alignof__ (uint64_t),
+		- ((uintptr_t) tmp) % __alignof__ (uint64_t),
 		key, key_len);
-      assert ((key - (char *) 0) % __alignof__ (uint64_t) == 0);
+      assert (((uintptr_t) key) % __alignof__ (uint64_t) == 0);
     }
 
-  if ((salt - (char *) 0) % __alignof__ (uint64_t) != 0)
+  if (((uintptr_t) salt) % __alignof__ (uint64_t) != 0)
     {
       char *tmp = (char *) alloca (salt_len + __alignof__ (uint64_t));
       salt = copied_salt =
 	memcpy (tmp + __alignof__ (uint64_t)
-		- (tmp - (char *) 0) % __alignof__ (uint64_t),
+		- ((uintptr_t) tmp) % __alignof__ (uint64_t),
 		salt, salt_len);
-      assert ((salt - (char *) 0) % __alignof__ (uint64_t) == 0);
+      assert (((uintptr_t) salt) % __alignof__ (uint64_t) == 0);
     }
 
 #ifdef USE_NSS