Here's a more useful backtrack of Gedit crashing (thanks to Josselin for his tips):
[Thread debugging using libthread_db enabled] [New Thread 47616068345712 (LWP 27460)] [New Thread 1074006368 (LWP 27464)] [New Thread 1082399072 (LWP 27465)] [Thread 1082399072 (LWP 27465) exited] [New Thread 1082399072 (LWP 27467)] [Thread 1082399072 (LWP 27467) exited] sys:1: PangoWarning: shape engine failure, expect ugly output. the offending font is 'SimSun-18030 12' sys:1: PangoWarning: pango_font_get_glyph_extents called with bad font, expect ugly output Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 47616068345712 (LWP 27460)] pango_fc_font_real_get_glyph (font=0xa8e180, wc=3749) at /usr/src/pango/pango1.0-1.14.8/./pango/pangofc-font.c:565 565 if (index > (FT_UInt)face->num_glyphs) (gdb) bt #0 pango_fc_font_real_get_glyph (font=0xa8e180, wc=3749) at /usr/src/pango/pango1.0-1.14.8/./pango/pangofc-font.c:565 #1 0x00002aaaac114261 in thai_make_glyph_uni (font_info=<value optimized out>, uc=3749) at /usr/src/pango/pango1.0-1.14.8/./modules/thai/thai-fc.c:230 #2 0x00002aaaac1137f0 in get_adjusted_glyphs_list (font_info=0x124d3b0, cluster=0x7fff355a6eb0, num_chrs=1, glyph_lists=0x7fff355a6ab0, shaping_table=0x2aaaac115060) at /usr/src/pango/pango1.0-1.14.8/./modules/thai/thai-shaper.c:179 #3 0x00002aaaac113f55 in thai_engine_shape (engine=<value optimized out>, font=0xa8e180, text=<value optimized out>, length=3762, analysis=<value optimized out>, glyphs=0x125e6a0) at /usr/src/pango/pango1.0-1.14.8/./modules/thai/thai-shaper.c:465 #4 0x00002b4e76a6401e in pango_shape (text=0x125df8b "ລາວ</option>", length=11, analysis=0xc15890, glyphs=0x125e6a0) at /usr/src/pango/pango1.0-1.14.8/./pango/shape.c:51 #5 0x00002b4e76a58d2c in shape_run (line=0xe17c70, state=0x7fff355a74d0, item=0xc15880) at /usr/src/pango/pango1.0-1.14.8/./pango/pango-layout.c:2771 #6 0x00002b4e76a5b147 in process_item (layout=0xa6c980, line=0xe17c70, state=0x7fff355a74d0, force_fit=0, no_break_at_end=0) at /usr/src/pango/pango1.0-1.14.8/./pango/pango-layout.c:2863 #7 0x00002b4e76a5b92b in pango_layout_check_lines (layout=0xa6c980) at /usr/src/pango/pango1.0-1.14.8/./pango/pango-layout.c:3065 #8 0x00002b4e76a5c17d in pango_layout_get_extents_internal (layout=0x0, ink_rect=0x0, logical_rect=0x7fff355a77d0, line_extents=0x0, real_width=0x0) at /usr/src/pango/pango1.0-1.14.8/./pango/pango-layout.c:2070 #9 0x00002b4e763f47f8 in gtk_text_layout_get_line_display () from /usr/lib/libgtk-x11-2.0.so.0 #10 0x00002b4e763f73e2 in ?? () from /usr/lib/libgtk-x11-2.0.so.0 #11 0x00002b4e763dfdbc in ?? () from /usr/lib/libgtk-x11-2.0.so.0 ---Type <return> to continue, or q <return> to quit--- #12 0x00002b4e763dfed2 in ?? () from /usr/lib/libgtk-x11-2.0.so.0 #13 0x00002b4e763dfed2 in ?? () from /usr/lib/libgtk-x11-2.0.so.0 #14 0x00002b4e763dfed2 in ?? () from /usr/lib/libgtk-x11-2.0.so.0 #15 0x00002b4e763e00df in _gtk_text_btree_validate () from /usr/lib/libgtk-x11-2.0.so.0 #16 0x00002b4e763f62f3 in gtk_text_layout_validate () from /usr/lib/libgtk-x11-2.0.so.0 #17 0x00002b4e764013ad in ?? () from /usr/lib/libgtk-x11-2.0.so.0 #18 0x00002b4e775fdc73 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0 #19 0x00002b4e77600abd in ?? () from /usr/lib/libglib-2.0.so.0 #20 0x00002b4e77600da6 in g_main_loop_run () from /usr/lib/libglib-2.0.so.0 #21 0x00002b4e763746b2 in gtk_main () from /usr/lib/libgtk-x11-2.0.so.0 #22 0x0000000000426849 in main () The problem only appears when a TTF font is set to 0400/root:root and fontconfig has a set of cache files in /var/cache/fontconfig/ (made by user root). Even if ~/.fontconfig/ contains a cache of the TTF in question, fontconfig will still prefer the system-wide cache in /var/cache/fontconfig/, causing a segmentation fault. When /var/cache/fontconfig/ is cleaned, fontconfig recreates correct cache files in ~/.fontconfig/. The crash will reappear when I start another Gnome app under root (such as Firestarter), since /var/cache/fontconfig/ will contain new cache files. When the TTF is set to a+r, the error also whithers away. Best regards Danai SAE-HAN 韓達耐 -- 題目:《牧童詩》 作者:黃庭堅(1045-1105) 騎牛遠遠過前村,短笛橫吹隔隴聞。 多少長安名利客,機關用盡不如君。