[Buildroot] [PATCH 2/2] package/ccache: add wrapper for internal toolchain

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Dear Karoly Kasza,

On Sun, 26 Apr 2015 11:21:02 +0200, Karoly Kasza wrote:
> This patch will make ccache to use mtime for compiler checks except for
> BR's internal toolchain, where using mtime would make ccache useless,
> because of the recompilations of the binaries. In this case we use
> a wrapper script and an md5 hash file with the BR .config options as
> suggested previously by Arnout.

Well, even for external toolchains using the mtime on the compiler in
$(HOST_DIR)/usr/bin will not work. Because the compiler in
$(HOST_DIR)/usr/bin is not actually the compiler, but a binary wrapper
built by Buildroot, for which the mtime will change at each build.

I must say I don't quite like the fact that the solution used here is
different between internal and external toolchain, but I haven't
thought too much of the problem.

How would ccache work with external toolchains?

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com