From aa2e1eb4453128ade5e3f52d54fd2086b4e7a8af Mon Sep 17 00:00:00 2001 From: Phil Bennett Date: Thu, 19 Nov 2009 23:18:09 +0000 Subject: [PATCH] Fixed possible NULL pointer dereference in video/dec0.c [Oliver Stoneberg] MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ---------- Forwarded message ---------- From: Oliver Stöneberg Date: Mon, Nov 16, 2009 at 7:59 PM Subject: possible NULL pointer dereference To: submit@mamedev.org This pacth fixes a possible NULL pointer dereference in src/mame/video/dec0.c reported by cppcheck. --- src/mame/video/dec0.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/mame/video/dec0.c b/src/mame/video/dec0.c index 35e6a4e5653..c24e8070ebf 100644 --- a/src/mame/video/dec0.c +++ b/src/mame/video/dec0.c @@ -229,14 +229,17 @@ static void custom_tilemap_draw(running_machine *machine, int column_offset=0, src_x=0, src_y=0; UINT32 scrollx=control1[0]; UINT32 scrolly=control1[1]; - int width_mask = src_bitmap->width - 1; - int height_mask = src_bitmap->height - 1; + int width_mask; + int height_mask; int row_scroll_enabled = (rowscroll_ptr && (control0[0]&0x4)); int col_scroll_enabled = (colscroll_ptr && (control0[0]&0x8)); if (!src_bitmap) return; + width_mask = src_bitmap->width - 1; + height_mask = src_bitmap->height - 1; + /* Column scroll & row scroll may per applied per pixel, there are shift registers for each which control the granularity of the row/col offset (down to per line level for row, and per 8 lines for column).