report a segment fault bug of systemtap

[Frank Ch. Eigler]

maliubiao wrote:

> [...]
> STACK TRACE:
>
> Pass 1: parsed user script and 100 library script(s) using
> 89752virt/29968res/2480shr/28316data kb, in 150usr/10sys/26180real ms.
>
> Program received signal SIGSEGV, Segmentation fault.
> 0x00007ffff777e946 in __strcmp_sse42 () from /lib64/libc.so.6
> (gdb) bt
> #0  0x00007ffff777e946 in __strcmp_sse42 () from /lib64/libc.so.6
> #1  0x00000000004d57ad in dwarf_atvar_query::atvar_query_cu (cudie=0x24028a0,
>     data=0x7fffffffba80) at tapsets.cxx:4192
> #2  0x000000000054a862 in dwflpp::iterate_over_cus (this=<optimized out>,
>     callback=0x4d5760 <dwarf_atvar_query::atvar_query_cu(Dwarf_Die*, void*)>,
>     data=0x7fffffffba80, want_types=false) at dwflpp.cxx:466
> [...]
> any idea ?


It seems like incomplete DWARF data can result in elfutils passing
NULL char*'s to the stap translator, which the latter is not always
prepared to tolerate.  We encountered this same problem here yesterday
and committed a patch.


- FChE