[ccache] Trouble sharing cache results when compiling with -isystem instead of -I

[Robert Houghton]

My companies build system uses -isystem for including 3rd party libraries
like python, Qt4 and others. Unfortunately, the paths from -isystem are
soft-linked to be relative to the personal build area instead of being
directly referenced.

Is looks like ccache v3.2.1 will not use the CCACHE_BASEDIR option when
considering paths provided by -isystem. Is this intentional, an oversight,
or a bug?

Attached are the logs from compiling a single .o and .so from two parallel
work areas

Thank you,
-Robert Houghton
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ccache_debug.log.first
Type: application/octet-stream
Size: 12001 bytes
Desc: not available
URL: <http://lists.samba.org/pipermail/ccache/attachments/20150903/e99b3ad6/ccache_debug.log.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ccache_debug.log.second
Type: application/octet-stream
Size: 11903 bytes
Desc: not available
URL: <http://lists.samba.org/pipermail/ccache/attachments/20150903/e99b3ad6/ccache_debug.log-0001.obj>