Linux From Scratch - Version 9.1-systemd-rc1

Chapter 5. Constructing a Temporary System

5.8. Libstdc++ from GCC-9.2.0

Libstdc++ is the standard C++ library. It is needed to compile C++ code (part of GCC is written in C++), but we had to defer its installation when we built gcc-pass1 because it depends on glibc, which was not yet available in /tools.

Approximate build time: 0.5 SBU
Required disk space: 878 MB

5.8.1. Installation of Target Libstdc++

[Note]

Note

Libstdc++ is part of the GCC sources. You should first unpack the GCC tarball and change to the gcc-9.2.0 directory.

Create a separate build directory for Libstdc++ and enter it: 

mkdir -v build
cd       build

Prepare Libstdc++ for compilation: 

../libstdc++-v3/configure           \
    --host=$LFS_TGT                 \
    --prefix=/tools                 \
    --disable-multilib              \
    --disable-nls                   \
    --disable-libstdcxx-threads     \
    --disable-libstdcxx-pch         \
    --with-gxx-include-dir=/tools/$LFS_TGT/include/c++/9.2.0

The meaning of the configure options:

--host=...

Indicates to use the cross compiler we have just built instead of the one in /usr/bin.

--disable-libstdcxx-threads

Since we have not yet built the C threads library, the C++ one cannot be built either.

--disable-libstdcxx-pch

This switch prevents the installation of precompiled include files, which are not needed at this stage.

--with-gxx-include-dir=/tools/$LFS_TGT/include/c++/9.2.0

This is the location where the standard include files are searched by the C++ compiler. In a normal build, this information is automatically passed to the Libstdc++ configure options from the top level directory. In our case, this information must be explicitly given.

Compile libstdc++ by running: 

make

Install the library: 

make install

Details on this package are located in Section 6.25.2, “Contents of GCC.”