export DEBIAN_BUILDARCH=architecture

export DEBIAN_BUILDGCCVER=gcc-version

g++ ...


The builder-c++ wrapper is normally used by calling g++ as usual. If the environment variable DEBIAN_BUILDARCH is not set, builder-c++ does nothing, and the real g++ is invoked with the specified arguments.

When the DEBIAN_BUILDARCH environment variable is set, builder-c++ invokes g++ with the specified arguments, plus -mcpu=DEBIAN_BUILDARCH -march=DEBIAN_BUILDARCH This has the effect of telling g++ to use architecture-specific optimizations without changing the command line. This is particularly useful for package builds.

If DEBIAN_BUILDGCCVER is not set, builder-c++ calls g++.real. If DEBIAN_BUILDGCCVER is set, builder-c++ calls g++-DEBIAN_BUILDGCCVER instead.



If set, the architecture to compile for. Useful values are pentium or pentiumpro.


If set, the version of g++ to be invoked. Useful values are 3.0 or 2.95.


The real g++ is renamed g++.real, and a diversion is registered with dpkg-divert(1). Thus builder-c++'s idea of the default g++ is dictated by whatever package installed /usr/bin/g++.

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