Compilation:
Download gcc1020.build from http://tinycorelinux.net/13.x/aarch64/tcz/src/gcc/
Before run, remove '--libdir=/usr/lib \'
replace '--enable-languages=c,c++ \' to '--enable-languages=c,c++,fortran \'

tce-load -i bash
nohup bash gcc1020.build &> build.log &

Packing:

cd gcc-10.2.0/build

make DESTDIR=/tmp/packing install

cd /tmp

mkdir -p packing-lib/usr/local/lib

# shared objects first
mv /tmp/packing/usr/local/lib/libgfortran.so* packing-lib/usr/local/lib/

strip --strip-unneeded packing-lib/usr/local/lib/libgfortran.so.5.0.0

# main extension
mkdir -p packing-main/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/

# f951, finclude
mv packing/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/f* packing-main/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/

# libcaf_single.a, libcaf_single.la
mv packing/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/libcaf_single.* packing-main/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/

# libgfortran.a, libgfortran.la, libgfortran.spec
mv packing/usr/local/lib/libgfortran.* packing-main/usr/local/lib/

# strip --strip-debug
trip --strip-debug packing-main/usr/local/lib/libgfortran.a packing-main/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/libcaf_single.a

# binaries
mkdir packing-main/usr/local/bin

mv packing/usr/local/bin/*gfortran packing-main/usr/local/bin

strip --strip-unneeded packing-main/usr/local/bin/* packing-main/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/ f951

# liblto_plugin (75K --> 76K)
mv packing/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/liblto_plugin.so.0.0.0 \
  packing-main/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/GFORTRAN-liblto_plugin.so.0.0.0

# tce.installed
#!/bin/sh

# LTO plugin
LTO_PLUGIN='/usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/GFORTRAN-liblto_plugin.so.0.0.0'
CURRENT='/usr/local/lib/bfd-plugins/liblto_plugin.so'
mkdir -p /usr/local/lib/bfd-plugins
cp -f $LTO_PLUGIN $CURRENT

# binaries
for BIN in /usr/local/bin/gfortran /usr/local/bin/aarch64-unknown-linux-gnu-gfortran /usr/local/lib/gcc/aarch64-unknown-linux-gnu/10.2.0/f951
do [ -L $BIN ] && cp -f $(busybox realpath $BIN) $BIN
done

# distcc
if [ -f /usr/local/tce.installed/distcc ]; then
  cd /usr/lib/distcc
  ln -s ../../local/bin/distcc gfortran
  ln -s ../../local/bin/distcc aarch64-unknown-linux-gnu-gfortran
  cd /usr/local/lib/distcc
  ln -s ../../bin/distcc gfortran
  ln -s ../../bin/distcc aarch64-unknown-linux-gnu-gfortran
fi