From 5394796fd3068316cd7247d494e52fcf60cb5c60 Mon Sep 17 00:00:00 2001 From: Eliseo Martínez Date: Wed, 17 Dec 2014 21:38:50 +0100 Subject: Fix warnings: window.c: win_close_othertab(): Np dereference: FP. Problem : Dereference of null pointer @ 1980. Diagnostic : False positive. Rationale : I haven't been able to find the real reason why this is signaled. Nonetheless, I've been able to track down the introduction of this warning to commit 77135447e09903b45d1482da45869946212f7904. The change there affecting this function is just a transformation maintaining semantics. So, this must be a FP, though I can't explain why. Analyzer thinks `win->w_buffer` can be null in line 1980, following an error path assuming win->w_buffer null at line 1819. Given that `win_close` function was not modified by mentioned commit, I don't understand why this path is analyzed after the changes, but not before them. Or if it's analyzed, why it's discarded before changes but not after them. I don't see anything in changes to `close_last_window_tabpage` that should affect to being able to deduce `win->w_buffer` is not null. Resolution : Assert buffer not null in `win_close_othertab`. Function comments state that passed window should have a buffer that can be hidden, which implies there should be a buffer. Reverting changes to `close_last_window_tabpage` in mentioned commit would be another way to fix this (tried and worked). But assert is preferred in this case because flat style reads better and we have some other way to fix it. --- src/nvim/window.c | 1 + 1 file changed, 1 insertion(+) (limited to 'src') diff --git a/src/nvim/window.c b/src/nvim/window.c index 0ed43b0184..029fcaac8b 100644 --- a/src/nvim/window.c +++ b/src/nvim/window.c @@ -1977,6 +1977,7 @@ void win_close_othertab(win_T *win, int free_buf, tabpage_T *tp) tabpage_T *ptp = NULL; int free_tp = FALSE; + assert(win->w_buffer); // to avoid np dereference warning in next line if (win->w_closing || win->w_buffer->b_closing) return; /* window is already being closed */ -- cgit