Why i am getting error when i type "make check" when i try to install GCC (10.2.0) when i try to make LFS
 

Making check in mpn
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpn'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpn'
Making check in mpz
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpz'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpz'
Making check in mpq
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpq'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpq'
Making check in mpf
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpf'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/mpf'
Making check in printf
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/printf'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/printf'
Making check in scanf
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/scanf'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/scanf'
Making check in rand
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/rand'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/rand'
Making check in cxx
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/cxx'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/cxx'
Making check in demos
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos'
Making check in calc
make[5]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos/calc'
make check-am
make[6]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos/calc'
make[6]: Nothing to be done for 'check-am'.
make[6]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos/calc'
make[5]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos/calc'
Making check in expr
make[5]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos/expr'
make[5]: Nothing to be done for 'check'.
make[5]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos/expr'
make[5]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos'
make[5]: Nothing to be done for 'check-am'.
make[5]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos'
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/demos'
Making check in tune
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/tune'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/tune'
Making check in doc
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/doc'
make[4]: Nothing to be done for 'check'.
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp/doc'
make[4]: Entering directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp'
make[4]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp'
make[3]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp'
make[2]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build/gmp'
make[1]: Leaving directory '/mnt/bulgarianos/sources/gcc-10.2.0/build'
make: *** [Makefile:2334: do-check] Error 2

Do you see an error reported in any of those directories?
Make check is telling you it did nothing.

cc1: error: no include path in which to search for stdc-predef.h

So this is the first pass. Then you should install Glibc headers for your host distribution. Depending on distribution, they may be in package libc6-dev, or glibc-headers, or something else.

See 2.2. Host System Requirements: