compilerplugins: fix clang plugin allowlists for sccache-dist

While icecream passes preprocessed (via -frewrite-includes) input to the
compiler on stdin, sccache-dist writes it to a file at the same location
as the source file in its sandbox.

So we need a new heuristic to detect that the input has
-frewrite-includes applied; there is not any variable that sccache sets,
users could have SCCACHE_CACHE_SIZE set but only if they use the disk
cache, so check CXX for now.

Also set SCCACHE_EXTRAFILES to include log-areas.dox required by plugin.

Change-Id: I4e00bfb0db7dab28f228fc0e85d753506e2c86b1
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/112480
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>

0 files changed, 0 insertions, 0 deletions