- Update to 4.9:
* Made ignore_options/CCACHE_IGNOREOPTIONS also skip the option from special
processing, similar to how --ccache-skip works.
* Added support for expanding environment variables references in all
configuration options.
* MSVC options /Fd, /FS and /MP are no longer included in the input hash.
* Made ccache terminate an ongoing compiler subprocess when terminated on all
platforms, not only on Unix.
* Added support for multiple -Xarch_* arguments matching -arch.
* Added a debug_level/CCACHE_DEBUGLEVEL configuration option, making it
possible to tell ccache to only write a log file for each compilation, not
other debug files.
* Added max_cache_size_kibibyte and max_files_in_cache fields in output from
ccache --print-stats.
* Paths after -Xclang -include are now rewritten to relative paths if
base_dir/CCACHE_BASEDIR is in effect.
* Added support for clang --analyze.
* Improved processing of input file arguments.
* Added support for st_Xtimensec fields in struct stat, thus improving
behavior on some BSDs when using newly created include files.
* Added support for the undocumented GCC/Clang option --include.
* Ccache now exits more gracefully on invalid sharded remote storage URLs.
* Made ccache bail out on too hard options -fmodules-ts, -fmodule-header,
-wrapper and -Xclang -ast-dump.
* Stopped relying on the st_blocks field in struct stat since it cannot be
trusted for filesystems such as ZFS that do transparent compression or
deduplication and adjust st_blocks some time in the future.
* Fixed crash on Windows for paths with only a drive letter.
* Made handling of Clang config options (such as --config-system-dir) more
robust.