patch 9.2.0471: vimvars di_key initialized at runtime

Problem:  evalvars_init() copies each vimvar's name into di_key at
          startup and runtime-checks that the name fits in
          DICTITEM16_KEY_LEN, even though all names are known at
          compile time.
Solution: Embed the name in di_key via the VV_NAME macro so the
          initialization happens at compile time.  Drop the
          runtime length check and the STRCPY loop (John Marriott).

closes: #20185

Signed-off-by: John Marriott <basilisk@internode.on.net>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/evalvars.c

@@ -37,7 +37,7 @@ static hashtab_T	compat_hashtab;
 #define VV_RO		2	// read-only
 #define VV_RO_SBX	4	// read-only in the sandbox
 
-#define VV_NAME(s, t)	s, {{t, 0, {0}}, 0, {0}}
+#define VV_NAME(s, t)	s, {{t, 0, {0}}, 0, {s}}
 
 typedef struct vimvar vimvar_T;
 
@@ -216,12 +216,6 @@ evalvars_init(void)
     for (i = 0; i < VV_LEN; ++i)
     {
 	p = &vimvars[i];
-	if (STRLEN(p->vv_name) > DICTITEM16_KEY_LEN)
-	{
-	    iemsg("Name too long, increase size of dictitem16_T");
-	    getout(1);
-	}
-	STRCPY(p->vv_di.di_key, p->vv_name);
 	if (p->vv_flags & VV_RO)
 	    p->vv_di.di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
 	else if (p->vv_flags & VV_RO_SBX)

src/version.c

@@ -729,6 +729,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    471,
 /**/
     470,
 /**/