How to compile a cross compiler using newlib

Versions used was
gcc-9.2 
binutils-2.33.1
newlib-3.2.0

gmp-6.1.2
mpc-1.1.0
mpfr-4.0.2
isl-0.22.1

Download, unpack and create symlinks
binutils, gcc, gmp, mpfr, and mpc: http://gnuftp.uib.no
isl (OPTIONAL dependency for gcc): http://isl.gforge.inria.fr/
newlib: ftp://sourceware.org/pub/newlib/

Build the cross compiler
First, figure out which target you need and that it is available for newlib/gcc
and do something like this (adjust your configure options for your needs).

export TARGET=m68k-elf
export TARGET=i386-elf

OBJDIR=/tmp/build
PREFIX=/tmp/cross-${TARGET}

export PATH=${PREFIX}/bin:${PATH}

mkdir -p ${OBJDIR}/binutils.${TARGET} && cd ${OBJDIR}/binutils.${TARGET} && \
${HOME}/binutils/configure --prefix=${PREFIX} --target=${TARGET} && \
sed -i 's/\-g /-pipe /' Makefile && \
make -j$(nproc) && make install-strip -j4

mkdir -p ${OBJDIR}/gcc.${TARGET} && cd ${OBJDIR}/gcc.${TARGET} && \
${HOME}/gcc/configure --prefix=${PREFIX} --libexecdir=${PREFIX}/lib --target=${TARGET} --enable-languages=c,c++ \
--disable-libstdcxx-pch --with-newlib && \
sed -i 's/\-g /-pipe /' Makefile && \
make all-gcc -j$(nproc) && make install-strip-gcc -j4

mkdir -p ${OBJDIR}/newlib.${TARGET} && cd ${OBJDIR}/newlib.${TARGET} && \
${HOME}/newlib/configure --prefix=${PREFIX} --target=${TARGET} && \
sed -i 's/\-g /-pipe /' Makefile && \
make -j$(nproc) && make install

cd ${OBJDIR}/gcc.${TARGET} && \
make -j$(nproc) && make install-strip -j4


Optional: Clean up (probably) unneeded files and directories
rm -rf ${PREFIX}/{include,lib/libcc*,share}
find ${PREFIX} -name '*.la' -delete