Warning fixes from Christos Zoulas

- shadowed variables
- signed/unsigned confusion
- const lossage
- incomplete structure initializations
- unused code

lib/gssapi/krb5/external.c

@@ -180,7 +180,7 @@ static gss_mo_desc krb5_mo[] = {
 	GSS_C_MA_SASL_MECH_NAME,
 	GSS_MO_MA,
 	"SASL mech name",
-	"GS2-KRB5",
+	rk_UNCONST("GS2-KRB5"),
 	_gss_mo_get_ctx_as_string,
 	NULL
     },
@@ -188,7 +188,7 @@ static gss_mo_desc krb5_mo[] = {
 	GSS_C_MA_MECH_NAME,
 	GSS_MO_MA,
 	"Mechanism name",
-	"KRB5",
+	rk_UNCONST("KRB5"),
 	_gss_mo_get_ctx_as_string,
 	NULL
     },
@@ -196,7 +196,7 @@ static gss_mo_desc krb5_mo[] = {
 	GSS_C_MA_MECH_DESCRIPTION,
 	GSS_MO_MA,
 	"Mechanism description",
-	"Heimdal Kerberos 5 mech",
+	rk_UNCONST("Heimdal Kerberos 5 mech"),
 	_gss_mo_get_ctx_as_string,
 	NULL
     },
@@ -214,19 +214,19 @@ static gss_mo_desc krb5_mo[] = {
     },
     {
 	GSS_C_MA_AUTH_TARG,
-	GSS_MO_MA
+	.flags = GSS_MO_MA
     },
     {
 	GSS_C_MA_AUTH_INIT_ANON,
-	GSS_MO_MA
+	.flags = GSS_MO_MA
     },
     {
 	GSS_C_MA_DELEG_CRED,
-	GSS_MO_MA
+	.flags = GSS_MO_MA
     },
     {
 	GSS_C_MA_INTEG_PROT,
-	GSS_MO_MA
+	.flags = GSS_MO_MA
     },
     {
 	GSS_C_MA_CONF_PROT,
@@ -273,7 +273,7 @@ static gss_mo_desc krb5_mo[] = {
 static gssapi_mech_interface_desc krb5_mech = {
     GMI_VERSION,
     "kerberos 5",
-    {9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
+    {9, rk_UNCONST("\x2a\x86\x48\x86\xf7\x12\x01\x02\x02") },
     0,
     _gsskrb5_acquire_cred,
     _gsskrb5_release_cred,
@@ -323,7 +323,13 @@ static gssapi_mech_interface_desc krb5_mech = {
     NULL,
     NULL,
     krb5_mo,
-    sizeof(krb5_mo) / sizeof(krb5_mo[0])
+    sizeof(krb5_mo) / sizeof(krb5_mo[0]),
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
 };
 
 gssapi_mech_interface