DR on callstack across signal handler

_From [derek.br...@gmail.com](https://code.google.com/u/117968039472581148324/) on December 10, 2010 17:57:51_

PR 413649

in a signal test I'm adding (based on DR's suite/tests/linux/signal0000.c) somehow DR got
on the callstack that DrMemory pulled from the test's handler. worth filing at least
as a curiosity: I don't remember the details of my DrMemory callstack heuristics but
I'm surprised this happened. haven't looked into the details.

the other error here is that the line# for the DR address is wrong: note the section warning:
a bug in postprocess.pl where it re-uses the last line# in that case

WARNING: module libdynamorio.so.1.4 not found: set DRMEMORY_LIB_PATH env var
WARNING: section for not found

Error `#1`: UNADDRESSABLE ACCESS 4 byte(s)
0x08048800 signal!signal_handler
/work/dr/tot/internal/clients/drmemory/tests/signal.c:115
0x002a4891 libdynamorio.so.1.4!signal_handler
/work/dr/tot/internal/clients/drmemory/tests/signal.c:115
0x004056e5 libc.so.6!__libc_start_main
??:0
0x08048771 signal!_start
??:0
0x08048b3c signal!__libc_csu_init
??:0

I put in a warning message before but did not suppress the line#
Put in better handling of unknown module/section

Leaving open for investigating DR on callstack

_Original issue: http://code.google.com/p/drmemory/issues/detail?id=125_