question about libgcc, libspuc++ in the l4re

Adam Lackorzynski adam at
Thu Jun 25 22:28:16 CEST 2015

On Thu Jun 25, 2015 at 15:37:38 -0400, Yuxin Ren wrote:
> I find in the src/l4/pkg directory, there are some libraries --
> libgcc, libstdc++-v3, and libsupc++. But in those libraries, I just
> found very little source code. Instead, they include many makefiles.
> Where is the source code of those libraries? And why are there those makefiles?

For libgcc there isn't any more source code because the package is only
exchanging some functionality in the libgcc provided by the used
compiler, and that only on ARM.
libsupc++ is part of libstdc++-v3, so the source code is taken from
there. libstdc++-v3 has all the source code related to libstdc++ which
is also used by e.g. libstdc++-headers.
This is separated for build dependency  as well as for runtime
dependency reasons. For example there are two libc versions, one with
L4-knowledge/multi-threading and one without. While you probably want to
have pthread and friends in your application, multi-threading
functionality (or even L4 functionality) functionality isn't available
in boot-up code.

Adam                 adam at

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