[uClibc]General Questions

[David McCullough]

Jivin Stanley lays it down ...
> Hi all, 
> 
> Currently i am working on sparc-linux for LEON. However there is some problem compiling libc. I would like to ask is
> 
> a) Is it possible to compile libc and libm separately ? It may be easier to compile pieces by pieces and easier to troubleshoot where all the bugs from. Also libm contains only algorithm and should be independent of system calls and i/o right ?

libm is very easy to get going,  I don't think it will cause you any
problems.  You should be able to remove the directory from the Makefile to
stop it building.  It isn't required.


> b) I set HAS_DOUBLE = true in the Config file, but when i compile libm for double, it complains about cmplxf.c and clog.c. it seems to me that my configuration is not updated into math.h. 

Not sre on this one.

> c) As i know, uClinux uses heavily on uClibc as the standard libraries, also uClinux uses flat binary format. Is is neccessary to convert individual object files into flat format ?

Only the final executable needs to be converted to flat format.

> e) i noticed most object files were strip off of .note and .comment, is it advisable to do a total strip i.e. using sparc-linux-strip <object file> with no flags ? I was able to save half the size, but is this advisable ?

No need to do this as the elf2flt process removes absolutely everything
that is not required.

> f) i would like the significance of libutil, libcrypt. libresolv, extra and ldso? are they neccessary for compiling libc ? In another words if these directories are removed, will compilation of libc continues ?

Most of these can be left until later depedning on the applications you are
building.

> g) I need some points to where to modify libc so that it can support LEON. I have the kernel running, and i have downloaded glibc-2.2.3 which i think may be handy, what are the directories that need attention ?

The most important bits I can think of are:

	Config
	libc/sysdeps/linux/sparc

Look in the other sysdep directories to determine what is required.

There appears to be some sparc support in uClibc already.  This may be a
good place to start if all sparc's are similar that is :-)  Otherwise you
might want to add a sparc-leon directory,

Cheers,
Davidm

-- 
David McCullough:  Ph: +61 7 3435 2815  Lineo (Where Open Meets Smart)
davidm at lineo.com   Fx: +61 7 3891 3630  825 Stanley St., W'gabba QLD 4102, Aus.