Add lib32 directories to chapter 6 GCC

[Armin]

I have received several questions and concerns about lib32 directories being displayed in chapter 6 GCC testing on i686, and that's not in the book. So it would be a nice idea to add it

SEARCH_DIR("/usr/i686-pc-linux-gnu/lib32")
SEARCH_DIR("/usr/local/lib32")
SEARCH_DIR("/lib32")
SEARCH_DIR("/usr/lib32")
SEARCH_DIR("/usr/i686-pc-linux-gnu/lib")
SEARCH_DIR("/usr/local/lib")
SEARCH_DIR("/lib")
SEARCH_DIR("/usr/lib");

If I recall correctly, there was a mailing list post about this too.

[Miklos Karacsony]

There is a more efficient way to do this. If you build a multilib enabled gcc just add these two seds before you run configure, and you're good to go:

sed -i 's@../lib)@../lib32)@g' gcc/config/i386/t-linux64
sed -i 's@../lib64@../lib@g' gcc/config/i386/t-linux64

This will modify the search paths so gcc will look for 64 bit libraries in ../lib & for 32 bit libraries in ../lib32

[Armin]

Standard dynamic linker location on 32 bit is /lib and on 64 bit is /lib64.

Some newer multilib setups use your approach (mine does), but then again, binary software will still look in /lib64 for dynamic linker since it's standard location. In LFS there's {,/usr}/lib64 -> {,/usr}/lib symlink to avoid using --libdir switches all over the place.

[bdubbs@…]

Fixed at revision 10530.