GCM_SET_KEY: Rename macro argument to avoid collision with struct tag.

Spotted by Nikos Mavrogiannopoulos.

ChangeLog

 2014-11-24  Niels Möller  <nisse@lysator.liu.se>
 
+	* gcm.h (GCM_SET_KEY): Rename macro argument KEY to avoid
+	collision with a struct tag. Spotted by Nikos Mavrogiannopoulos.
+
 	* testsuite/eddsa-verify-test.c (test_eddsa): Fixed test case bug,
 	showing up as use of uninitialized data with valgrind.
 

gcm.h

@@ -151,9 +151,9 @@ gcm_digest(struct gcm_ctx *ctx, const struct gcm_key *key,
   { struct gcm_key key; struct gcm_ctx gcm; type cipher; }
 
 /* NOTE: Avoid using NULL, as we don't include anything defining it. */
-#define GCM_SET_KEY(ctx, set_key, encrypt, key)			\
+#define GCM_SET_KEY(ctx, set_key, encrypt, gcm_key)			\
   do {								\
-    (set_key)(&(ctx)->cipher, (key));				\
+    (set_key)(&(ctx)->cipher, (gcm_key));				\
     if (0) (encrypt)(&(ctx)->cipher, 0, (void *)0, (void *)0);	\
     gcm_set_key(&(ctx)->key, &(ctx)->cipher,			\
 		(nettle_cipher_func *) (encrypt));		\