I get an error making M4 regarding the file libgmp.so10.

It gives the error that it can't be found.

Sorry can't reproduce now coz I restarted the LFS several times and got tiered of it.

Can anyone help?

I am now @ 6.7 waiting for a sollution b4 I go on.

bash version-check.sh
bash, version 4.2.37(1)-release
/bin/sh -> /bin/bash
Binutils: (GNU Binutils for Ubuntu) 2.22.90.20120924
bison (GNU Bison) 2.5
/usr/bin/yacc -> /usr/bin/bison.yacc
bzip2, Version 1.0.6, 6-Sept-2010.
Coreutils: 8.13
diff (GNU diffutils) 3.2
find (GNU findutils) 4.4.2
GNU Awk 4.0.1
/usr/bin/awk -> /usr/bin/gawk
gcc (Ubuntu/Linaro 4.7.2-2ubuntu1) 4.7.2
(Ubuntu EGLIBC 2.15-0ubuntu20) 2.15
grep (GNU grep) 2.12
gzip 1.5
Linux version 3.5.0-21-generic (buildd@roseapple) (gcc version 4.7.2 (Ubuntu/Linaro 4.7.2-2ubuntu1) ) #32-Ubuntu SMP Tue Dec 11 18:52:46 UTC 2012
m4 (GNU M4) 1.4.16
GNU Make 3.81
patch 2.6.1
Perl version='5.14.2';
GNU sed version 4.2.1
tar (GNU tar) 1.26
Texinfo: makeinfo (GNU texinfo) 4.13
xz (XZ Utils) 5.1.0alpha
gcc compilation OK

Without any error message we cannot help you. I would suggest you redo the M4 chapter (maybe you made a typo).

Posting the output of the version check is useless at this point. What is build in chapter 5 is used in chapter 6, isolating the new system from the host distribution (1.1. How to Build an LFS System)

Redo the http://www.linuxfromscratch.org/lfs/...ter06/gmp.html section and pay careful attention to the test suite.