From c73cf3548e7166a4ccffc578699c394b360ed0f5 Mon Sep 17 00:00:00 2001 From: Eli Zaretskii Date: Sat, 7 Jul 2018 10:45:45 +0300 Subject: [PATCH] Fix recent change in window.c * src/window.c (scroll_command): Fix minor inefficiency in last change: don't call Fset_buffer if the buffer is already set to be what we want. (Bug#31988) --- src/window.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/src/window.c b/src/window.c index 8d1aed46dff..d3c72570dd1 100644 --- a/src/window.c +++ b/src/window.c @@ -5652,12 +5652,17 @@ scroll_command (Lisp_Object window, Lisp_Object n, int direction) w = XWINDOW (window); other_window = ! EQ (window, selected_window); - /* If given window's buffer isn't current, make it current for - the moment. But don't screw up if window_scroll gets an error. */ + /* If given window's buffer isn't current, make it current for the + moment. If the window's buffer is the same, but it is not the + selected window, we need to save-excursion to avoid affecting + point in the selected window (which would cause the selected + window to scroll). Don't screw up if window_scroll gets an + error. */ if (other_window || XBUFFER (w->contents) != current_buffer) { record_unwind_protect_excursion (); - Fset_buffer (w->contents); + if (XBUFFER (w->contents) != current_buffer) + Fset_buffer (w->contents); } if (other_window) -- 2.39.2