Bug 648530 – net-analyzer/nettop-0.2.3-r2 SIGFPE Floating point exception (core dumped)

• Product: Gentoo Linux
• Status: UNCONFIRMED ---

[Description Xuefer 2018-02-22 16:51:47 UTC]

```
# gdb `which nettop` core
GNU gdb (Gentoo 8.1 p1) 8.1
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-pc-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.gentoo.org/>.
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For help, type "help".
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Reading symbols from /usr/sbin/nettop...(no debugging symbols found)...done.
[New LWP 29876]
[New LWP 29874]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Core was generated by `nettop'.
Program terminated with signal SIGFPE, Arithmetic exception.
#0  0x00000000004028a0 in ?? ()
[Current thread is 1 (Thread 0x7ffff6ac8700 (LWP 29876))]
(gdb) bt
#0  0x00000000004028a0 in ?? ()
#1  0x0000000000403d6e in ?? ()
#2  0x00007ffff7bbf92a in start_thread (arg=0x7ffff6ac8700) at pthread_create.c:465
#3  0x00007ffff772c1df in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb)
```

[Comment 1 Xuefer 2018-02-22 16:54:04 UTC]

Created attachment 520556 [details]
emerge --info nettop

[Comment 2 Jeroen Roovers (RETIRED) 2018-02-23 06:54:25 UTC]

Do not CC architecture teams yourself. It's completely pointless.

[Comment 3 Jeroen Roovers (RETIRED) 2018-02-23 08:53:06 UTC]

(In reply to Xuefer from comment #0)
> Program terminated with signal SIGFPE, Arithmetic exception.
> #0  0x00000000004028a0 in ?? ()

Could you re-emerge with CFLAGS=-g so we can see what "??" is?

[Comment 4 Xuefer 2018-02-24 10:11:45 UTC]

```
Program terminated with signal SIGFPE, Arithmetic exception.
#0  0x00000000004028f0 in screen_update () at nettop.c:484
484                     valp = (sorted[i]->count * 10000) / sump;
[Current thread is 1 (LWP 3193)]
(gdb) bt
#0  0x00000000004028f0 in screen_update () at nettop.c:484
#1  0x0000000000403dbe in ui_run () at nettop.c:670
#2  0x00007ffff7bbda76 in start_thread () from /lib64/libpthread.so.0
#3  0x00007ffff772605f in clone () from /lib64/libc.so.6
```

[Comment 5 Xuefer 2018-02-24 10:22:46 UTC]

Created attachment 520870 [details]
build.log.gz

[Comment 6 Jeroen Roovers (RETIRED) 2018-02-24 12:01:19 UTC]

(In reply to Xuefer from comment #4)
> ```
> Program terminated with signal SIGFPE, Arithmetic exception.
> #0  0x00000000004028f0 in screen_update () at nettop.c:484
> 484                     valp = (sorted[i]->count * 10000) / sump;
> [Current thread is 1 (LWP 3193)]
> (gdb) bt
> #0  0x00000000004028f0 in screen_update () at nettop.c:484

            valp = (sorted[i]->count * 10000) / sump;

Apparently sump can be 0 sometimes.