updated for version 7.4.446

Problem:    In some situations, when setting up an environment to trigger an
            autocommand, the environment is not properly restored.
Solution:   Check the return value of switch_win() and call restore_win()
            always.  (Daniel Hahler)

src/eval.c

@@ -12086,8 +12086,9 @@ f_gettabvar(argvars, rettv)
     {
 	/* Set tp to be our tabpage, temporarily.  Also set the window to the
 	 * first window in the tabpage, otherwise the window is not valid. */
-	switch_win(&oldcurwin, &oldtabpage, tp->tp_firstwin, tp, TRUE);
+	if (switch_win(&oldcurwin, &oldtabpage, tp->tp_firstwin, tp, TRUE)
-
+									== OK)
+	{
 	    /* look up the variable */
 	    /* Let gettabvar({nr}, "") return the "t:" dictionary. */
 	    v = find_var_in_ht(&tp->tp_vars->dv_hashtab, 't', varname, FALSE);
@@ -12096,6 +12097,7 @@ f_gettabvar(argvars, rettv)
 		copy_tv(&v->di_tv, rettv);
 		done = TRUE;
 	    }
+	}
 
 	/* restore previous notion of curwin */
 	restore_win(oldcurwin, oldtabpage, TRUE);
@@ -12233,8 +12235,8 @@ getwinvar(argvars, rettv, off)
     {
 	/* Set curwin to be our win, temporarily.  Also set the tabpage,
 	 * otherwise the window is not valid. */
-	switch_win(&oldcurwin, &oldtabpage, win, tp, TRUE);
+	if (switch_win(&oldcurwin, &oldtabpage, win, tp, TRUE) == OK)
-
+	{
 	    if (*varname == '&')	/* window-local-option */
 	    {
 		if (get_option_tv(&varname, rettv, 1) == OK)
@@ -12244,13 +12246,15 @@ getwinvar(argvars, rettv, off)
 	    {
 		/* Look up the variable. */
 		/* Let getwinvar({nr}, "") return the "w:" dictionary. */
-	    v = find_var_in_ht(&win->w_vars->dv_hashtab, 'w', varname, FALSE);
+		v = find_var_in_ht(&win->w_vars->dv_hashtab, 'w',
+							      varname, FALSE);
 		if (v != NULL)
 		{
 		    copy_tv(&v->di_tv, rettv);
 		    done = TRUE;
 		}
 	    }
+	}
 
 	/* restore previous notion of curwin */
 	restore_win(oldcurwin, oldtabpage, TRUE);
@@ -17252,10 +17256,9 @@ setwinvar(argvars, rettv, off)
     if (win != NULL && varname != NULL && varp != NULL)
     {
 #ifdef FEAT_WINDOWS
-	if (switch_win(&save_curwin, &save_curtab, win, tp, TRUE) == FAIL)
+	if (switch_win(&save_curwin, &save_curtab, win, tp, TRUE) == OK)
-	    return;
 #endif
-
+	{
 	    if (*varname == '&')
 	    {
 		long	numval;
@@ -17279,7 +17282,7 @@ setwinvar(argvars, rettv, off)
 		    vim_free(winvarname);
 		}
 	    }
-
+	}
 #ifdef FEAT_WINDOWS
 	restore_win(save_curwin, save_curtab, TRUE);
 #endif

src/misc2.c

@@ -1040,7 +1040,8 @@ free_all_mem()
     entered = TRUE;
 
 # ifdef FEAT_AUTOCMD
-    block_autocmds();	    /* don't want to trigger autocommands here */
+    /* Don't want to trigger autocommands from here on. */
+    block_autocmds();
 # endif
 
 # ifdef FEAT_WINDOWS

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    446,
 /**/
     445,
 /**/

src/window.c

@@ -1271,7 +1271,7 @@ win_init(newp, oldp, flags)
 }
 
 /*
- * Initialize window "newp" from window"old".
+ * Initialize window "newp" from window "old".
  * Only the essential things are copied.
  */
     static void
@@ -6662,8 +6662,8 @@ restore_snapshot_rec(sn, fr)
 	|| defined(PROTO)
 /*
  * Set "win" to be the curwin and "tp" to be the current tab page.
- * restore_win() MUST be called to undo.
+ * restore_win() MUST be called to undo, also when FAIL is returned.
- * No autocommands will be executed.
+ * No autocommands will be executed until restore_win() is called.
  * When "no_display" is TRUE the display won't be affected, no redraw is
  * triggered, another tabpage access is limited.
  * Returns FAIL if switching to "win" failed.
@@ -6696,12 +6696,7 @@ switch_win(save_curwin, save_curtab, win, tp, no_display)
 	    goto_tabpage_tp(tp, FALSE, FALSE);
     }
     if (!win_valid(win))
-    {
-# ifdef FEAT_AUTOCMD
-	unblock_autocmds();
-# endif
 	return FAIL;
-    }
     curwin = win;
     curbuf = curwin->w_buffer;
 # endif