[ccache] direct mode design bug

[Christian Lohmaier]

Hi Joel, *,

On Sun, Nov 4, 2012 at 8:10 PM, Joel Rosdahl <joel at rosdahl.net> wrote:
>
> The direct mode, which was introduced in version 3.0 almost three years
> ago, has a design bug. The essence of the problem is that in the direct
> mode, ccache records header files that were used by the compiler, but it
> doesn't record header files that were not used but could have been used if
> they existed.

I wouldn't call it a bug, it is just how it works.

If you're going to "fix" this, then please by introducing a "safe
direct" mode in addition to the current direct mode.

If people create headers with the same name all over the place, only
they should "suffer".

>From my understanding this is impossible to fix without sacrifying
what direct mode is about. (avoiding to run the preprocessor, or
something similar that simulates a preprocessor)

ciao
Christian