Re: Sylpheed crashing

["Ian D. Leroux" <idleroux%fastmail.fm@localhost>]

I've finally found the time to take another stab at my intermittent
sylpheed segfault.  To recap, sylpheed will sometimes get SIGSEGV, with
an obviously corrupt stack (null pointer in the backtrace) when
iconv_close tries to dlclose one of the citrus modules.  The latest
thing I tried is running sylpheed under gdb until the crash occurred
and then manually unwinding the stack back past the corrupt entry.
That leads to a much simpler backtrace than the last one I sent out
(see below).

Does any of it look suspicious to anyone?  In particular, is there
anything that might let us ascertain whether this is a base-system bug
or a sylpheed bug, so that I can ask the appropriate people for help?
Any ideas for other tests that might be helpful?  Are there any known
gotchas when calling our iconv implementation (i.e.: what mistakes can
a client make such that something as fundamental as dlclose would get
borked)?

Thanks for any and all advice,

-- IDL

Thread 1 received signal SIGSEGV, Segmentation fault.
0x0000709a3b2c1df3 in ?? ()
(gdb) bt
#0  0x0000709a3b2c1df3 in ?? ()
#1  0x0000709a3a600955 in ?? () from /usr/lib/i18n/libmapper_646.so.5.0
#2  0x0000709a4bc045e0 in ?? ()
#3  0x0000709a3a600f49 in _fini () from /usr/lib/i18n/libmapper_646.so.5.0
#4  0x0000000000000000 in ?? ()
(gdb) set $pc = *(void **)$rsp
(gdb) set $rsp = $rsp + 8
(gdb) set $pc = *(void **)$rsp
(gdb) set $rsp = $rsp + 8
(gdb) set $pc = *(void **)$rsp
(gdb) set $rsp = $rsp + 8
(gdb) set $pc = *(void **)$rsp
(gdb) set $rsp = $rsp + 8
(gdb) bt
#0  0x0000000000000000 in ?? ()
#1  0x00007f7fe6a03ad8 in _rtld_call_function_void (obj=<optimized out>,
addr=123807706648384) at /build/src/libexec/ld.elf_so/rtld.h:498
#2  _rtld_call_initfini_function (obj=<optimized out>, mask=0x7f7fff173a10,
func=<optimized out>) at /build/src/libexec/ld.elf_so/rtld.c:142
#3  _rtld_call_fini_function (cur_objgen=<optimized out>, mask=<optimized out>,
obj=<optimized out>) at /build/src/libexec/ld.elf_so/rtld.c:157
#4  _rtld_call_fini_functions (force=<optimized out>, mask=<optimized out>) at
/build/src/libexec/ld.elf_so/rtld.c:203
#5  _rtld_unload_object (mask=mask@entry=0x7f7fff173a10,
root=root@entry=0x709a4bc06400, do_fini_funcs=do_fini_funcs@entry=true)
    at /build/src/libexec/ld.elf_so/rtld.c:864
#6  0x00007f7fe6a03ff9 in _rtld_unload_object (do_fini_funcs=true,
root=0x709a4bc06400, mask=0x7f7fff173a10) at
/build/src/libexec/ld.elf_so/rtld.c:857
#7  dlclose (handle=<optimized out>) at /build/src/libexec/ld.elf_so/rtld.c:958
#8  0x0000709a3ef0aec3 in _citrus_unload_module (handle=<optimized out>) at
/build/src/lib/libc/citrus/citrus_module.c:344
#9  0x0000709a3eea4f56 in mapper_close (cm=0x709a47121d40) at
/build/src/lib/libc/citrus/citrus_mapper.c:197
#10 0x0000709a3eea5258 in _citrus_mapper_close (cm=<optimized out>) at
/build/src/lib/libc/citrus/citrus_mapper.c:389
#11 0x0000709a3d200a81 in close_dsts (dl=dl@entry=0x709a47115e38) at
/build/src/lib/libc/citrus/modules/citrus_iconv_std.c:200
#12 0x0000709a3d200ad2 in close_srcs (sl=sl@entry=0x709a47115d70) at
/build/src/lib/libc/citrus/modules/citrus_iconv_std.c:257
#13 0x0000709a3d200b20 in _citrus_iconv_std_iconv_uninit_shared (ci=<optimized
out>) at /build/src/lib/libc/citrus/modules/citrus_iconv_std.c:412
#14 0x0000709a3ee71680 in close_shared (ci=0x709a4955ca00) at
/build/src/lib/libc/citrus/citrus_iconv.c:145
#15 release_shared (ci=0x709a4955ca00) at
/build/src/lib/libc/citrus/citrus_iconv.c:318
#16 0x0000709a3ee71d50 in _citrus_iconv_close (cv=0x709a479cf180) at
/build/src/lib/libc/citrus/citrus_iconv.c:390
#17 0x0000709a3ee5cc1f in _iconv_close (handle=<optimized out>) at
/build/src/lib/libc/iconv/iconv.c:81
#18 0x0000709a4a822289 in conv_iconv_strdup (inbuf=0x7f7fff173c20 "> On Mon, May
22, 2017 at 06:28:59PM -0000, yancm%sdf.org@localhost wrote:\n",
    src_code=0x709a479cf0d0 "iso-8859-1", dest_code=0x709a4a876bdb "UTF-8",
error=0x0) at codeconv.c:1525
#19 0x0000709a4a821f17 in conv_convert (conv=0x709a479e1760,
inbuf=0x7f7fff173c20 "> On Mon, May 22, 2017 at 06:28:59PM -0000, yancm%sdf.org@localhost
wrote:\n")
    at codeconv.c:1380
#20 0x000000000045c6f3 in textview_write_line (textview=0x709a4b3cc580,
    str=0x7f7fff173c20 "> On Mon, May 22, 2017 at 06:28:59PM -0000,
yancm%sdf.org@localhost wrote:\n", conv=0x709a479e1760) at textview.c:1544
#21 0x000000000045bb69 in textview_write_body (textview=0x709a4b3cc580,
mimeinfo=0x709a4b31cd40, fp=0x709a3f176ae8, charset=0x709a479cf4d0 "iso-8859-1")
    at textview.c:1220
#22 0x000000000045b63b in textview_add_part (textview=0x709a4b3cc580,
mimeinfo=0x709a4b31cd40, fp=0x709a3f176ae8) at textview.c:1091
#23 0x000000000045b9c3 in textview_add_parts (textview=0x709a4b3cc580,
mimeinfo=0x709a4b31cd40, fp=0x709a3f176ae8) at textview.c:1176
#24 0x00000000004597d4 in textview_show_message (textview=0x709a4b3cc580,
mimeinfo=0x709a4b31cd40,
    file=0x709a495aeeb0
"/home/idleroux/.sylpheed-2.0/imapcache/mail.messagingengine.com/idleroux%fastmail.fm@localhost/INBOX/53124")
at textview.c:535
#25 0x00000000004560a7 in messageview_show (messageview=0x709a4ab66760,
msginfo=0x709a48d22080, all_headers=0) at messageview.c:625
#26 0x0000000000448fbf in summary_display_msg_full (summaryview=0x709a4ab13000,
iter=0x7f7fff177f60, new_window=0, all_headers=0, redisplay=0)
    at summaryview.c:2854
#27 0x0000000000448dfb in summary_display_msg (summaryview=0x709a4ab13000,
iter=0x7f7fff177f60) at summaryview.c:2808
#28 0x0000000000453dc3 in summary_display_msg_idle_func (data=0x709a4ab13000) at
summaryview.c:6245
#29 0x0000709a3fe4467e in g_main_context_dispatch () from
/usr/pkg/lib/libglib-2.0.so.0
#30 0x0000709a3fe44995 in g_main_context_iterate.isra () from
/usr/pkg/lib/libglib-2.0.so.0
#31 0x0000709a3fe44c7e in g_main_loop_run () from /usr/pkg/lib/libglib-2.0.so.0
#32 0x0000709a48f2b50e in gtk_main () from /usr/pkg/lib/libgtk-x11-2.0.so.0
#33 0x000000000042dc1e in main (argc=1, argv=0x7f7fff1781a8) at main.c:389
(gdb)