Comment 2 for bug 456907

I should add, once you do, test it with a PAC style http_proxy setting and witness the segfault:

$ http_proxy=pac+http://linux/proxy.pac proxy
http://www.yahoo.com/
Segmentation fault (core dumped)

Unfortunately gdb fails to help:

$ http_proxy=pac+http://linux/proxy.pac gdb proxy
GNU gdb (GDB) 7.0-ubuntu
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This GDB was configured as "i486-linux-gnu".
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<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/bin/proxy...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/proxy
[Thread debugging using libthread_db enabled]
Cannot find new threads: generic error