background

ccache is a nice tool, but we certainly realized some issue of its behavior in this project, that could waste your time instead of save your time. So it's default off now, unless you manually enable it.

issue that could appear if you enable it

Just keep in mind that these issues could be made:

• When you compiled with ccache enabled, and use git to merge/pull new changes, it can only detect a part of your change, and would compile fail. It cannot be fixed by make clean, you hvae to delete the build dir and start over.
• Sometimes ccache cause linking stage took extremely long.
• Unknown linking error until you make clean and start over again.

I want enable it anyway

If you are aware of these issue and you are sure you are able to realized them, when they appear, follow this to enable ccache:

for make:

turn on

#(...other steps that in compile guide...)
mkdir build
cd build
cmake -DUSE_CCACHE=ON ..   
make -j
#(...other steps that in compile guide...)

turn off

#(...other steps that in compile guide...)
mkdir build
cd build
cmake -DUSE_CCACHE=OFF ..   
make -j
#(...other steps that in compile guide...)

default behavior (off) (if you turned it on, this will became on until you turn it off again)

#(...other steps that in compile guide...)
mkdir build
cd build
cmake ..   
make -j
#(...other steps that in compile guide...)

for ninja:

turn on

#(...other steps that in compile guide...)
mkdir build
cd build
cmake -G Ninja -DUSE_CCACHE=ON .. 
ninja
#(...other steps that in compile guide...)

turn off

#(...other steps that in compile guide...)
mkdir build
cd build
cmake -G Ninja -DUSE_CCACHE=OFF .. 
ninja
#(...other steps that in compile guide...)

default behavior (off) (if you turned it on, this will became on until you turn it off again)

#(...other steps that in compile guide...)
mkdir build
cd build
cmake -G Ninja .. 
ninja
#(...other steps that in compile guide...)