patch 7.4.815

Problem:    Invalid memory access when doing ":call g:".
Solution:   Check for an empty name. (Dominique Pelle)

src/eval.c

@@ -21371,6 +21371,7 @@ find_var_in_ht(ht, htname, varname, no_autoload)
 
 /*
  * Find the hashtab used for a variable name.
+ * Return NULL if the name is not valid.
  * Set "varname" to the start of name without ':'.
  */
     static hashtab_T *
@@ -21380,6 +21381,8 @@ find_var_ht(name, varname)
 {
     hashitem_T	*hi;
 
+    if (name[0] == NUL)
+	return NULL;
     if (name[1] != ':')
     {
 	/* The name must not start with a colon or #. */

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    815,
 /**/
     814,
 /**/