Fixed memory leak in ":ownsyntax".

runtime/doc/eval.txt

@@ -1163,13 +1163,6 @@ b:changedtick	The total number of changes to the current buffer.  It is
 A variable name that is preceded with "w:" is local to the current window.  It
 is deleted when the window is closed.
 
-One local window variable is predefined:
-					*w:ownsyntax-variable* *ownsyntax*
-w:ownsyntax	Set to 1 if the window has an independent syntax installed
-		via the |:ownsyntax| command. The default for a window is
-		0. Syntax scripts can use this to determine whether they
-		should set b:current_syntax or w:current_syntax.
-
 						*tabpage-variable* *t:var*
 A variable name that is preceded with "t:" is local to the current tab page,
 It is deleted when the tab page is closed. {not available when compiled

src/eval.c

@@ -3884,11 +3884,6 @@ get_user_var_name(xp, idx)
 	    ++hi;
 	return cat_prefix_varname('w', hi->hi_key);
     }
-    if (wdone == ht->ht_used)
-    {
-	++wdone;
-	return (char_u *)"w:ownsyntax";
-    }
 
 #ifdef FEAT_WINDOWS
     /* t: variables */
@@ -18758,18 +18753,6 @@ get_var_tv(name, len, rettv, verbose)
 	tv = &atv;
     }
 
-    if (STRCMP(name, "w:ownsyntax") == 0)
-    {
-	atv.v_type = VAR_NUMBER;
-#ifdef FEAT_SYN_HL
-	atv.vval.v_number = (curwin->w_s != &curwin->w_buffer->b_s) ? 1 : 0;
-#else
-	atv.vval.v_number = 0;
-#endif
-	tv = &atv;
-    }
-
-
     /*
      * Check for user-defined variables.
      */
@@ -19292,6 +19275,7 @@ find_var_ht(name, varname)
 
 /*
  * Get the string value of a (global/local) variable.
+ * Note: see get_tv_string() for how long the pointer remains valid.
  * Returns NULL when it doesn't exist.
  */
     char_u *

src/syntax.c

@@ -3537,7 +3537,6 @@ syn_cmd_clear(eap, syncing)
 	    syntax_clear(curwin->w_s);
 	    if (curwin->w_s == &curwin->w_buffer->b_s)
 		do_unlet((char_u *)"b:current_syntax", TRUE);
-	    else
 	    do_unlet((char_u *)"w:current_syntax", TRUE);
 
 	}
@@ -6157,6 +6156,9 @@ ex_syntax(eap)
 ex_ownsyntax(eap)
     exarg_T	*eap;
 {
+    char_u	*old_value;
+    char_u	*new_value;
+
     if (curwin->w_s == &curwin->w_buffer->b_s)
     {
 	curwin->w_s = (synblock_T *)alloc(sizeof(synblock_T));
@@ -6170,7 +6172,26 @@ ex_ownsyntax(eap)
 	clear_string_option(&curwin->w_s->b_p_spl);
 #endif
     }
+
+    /* save value of b:current_syntax */
+    old_value = get_var_value((char_u *)"b:current_syntax");
+    if (old_value != NULL)
+	old_value = vim_strsave(old_value);
+
+    /* Apply the "syntax" autocommand event, this finds and loads the syntax
+     * file. */
     apply_autocmds(EVENT_SYNTAX, eap->arg, curbuf->b_fname, TRUE, curbuf);
+
+    /* move value of b:current_syntax to w:current_syntax */
+    new_value = get_var_value((char_u *)"b:current_syntax");
+    set_internal_string_var((char_u *)"w:current_syntax", new_value);
+
+    /* restore value of b:current_syntax */
+    if (old_value != NULL)
+    {
+	set_internal_string_var((char_u *)"b:current_syntax", old_value);
+	vim_free(old_value);
+    }
 }
 
     int

src/window.c

@@ -4410,7 +4410,10 @@ win_free(wp, tp)
 #ifdef FEAT_SYN_HL
     /* free independent synblock */
     if (wp->w_s != &wp->w_buffer->b_s)
+    {
+	syntax_clear(wp->w_s);
 	vim_free(wp->w_s);
+    }
 #endif
 
 #ifdef FEAT_AUTOCMD