[gentoo-dev] How to set CXX compiler?

[Xianwen Chen (陈贤文)]

Dear all, 

I got a newbie question. 

I need to patch a Makefile, for a package I am working on my own layman
repo. The package is sci-geosciences/sosicon. It converts spatial data
that is in sosi format, which is the national standard format in Norway,
to a shape file or to PostGIS. 

In the Makefile, it is written that 

cc = g++ 

I would like to use sed to patch it so that it ebuild knows which g++ to
use. For example, depending on whether ccache is set, ebuild shall know
whether to use ccache. 

I tried to replace g++ with ${CXX}$. I also tried to replace g++ with
$(tc-getCXX). Neither was working. I have also tried a number of other
potential solutions that I thought might work. 

Any hint, please? 

Yours sincerely, 

Xianwen