Detect if a compiler is using ccache - makefile

Question

ccache does not support some compiler options (e.g. --coverage). If there is an unsupported compiler options it compiles but the cache is not used.
There are more than one ways how to enable ccache (modifying PATH, using CC/CXX environment variables).
I would like to detect if the compiler uses ccache and if yes disable the unsupported compiler options.
The best i have come up with is something like this:
CC = $(shell which $(CC))
ifeq (,$(findstring ccache,$(CC)))
Any ideas how to improve this?

Answer 1

This might be a more elegant solution:
ifeq ($(shell readlink -f `which $(CC)`),$(shell which ccache))
echo "Using ccache"
else
echo "Not using ccache"
endif

Answer 2

Smani's solution may not work, depending on how ccache in configured (e.g. in RedHat Linux's ccache 3.3.4, t the compiler symlinks in /usr/lib64/ccache/ point to /usr/bin/ccache but which ccache returns /bin/ccache).
This solution doesn't care where ccache is located and even works if ccache is used as a prefix:
ifeq ($(shell $(CC) -xc -c - --ccache-skip </dev/null 2>&1),)
echo "Using ccache"
else
echo "Not using ccache"
endif
This works by compiling an empty file and checking whether the compiler knows about the ccache --ccache-skip flag.
Note that once you know ccache is enabled, instead of omitting the --coverage flag, you could preface it with --ccache-skip.
Note also that even if ccache is in the path, it may be disabled by the CCACHE_DISABLE environment variable or by the ccache.conf file.