ubuntu Compile libxml2-2.9.1
./configure & make & make install
Error Messages:

lto1: fatal error: bytecode stream in file ‘/home/…/anaconda3/envs/rasa/lib/python3.6/config-3.6m-x86_64-linux-gnu/libpython3.6m.a’ generated with LTO version 6.2 instead of the expected 8.1
compilation terminated.
lto-wrapper: fatal error: gcc returned 1 exit status
compilation terminated.
/usr/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status
make[4]: *** [Makefile:519: libxml2mod.la] Error 1
make[4]: Leaving directory ‘/home/…/libxml2-2.9.1/python’
make[3]: *** [Makefile:607: all-recursive] Error 1
make[3]: Leaving directory ‘/home/…/libxml2-2.9.1/python’
make[2]: *** [Makefile:450: all] Error 2
make[2]: Leaving directory ‘/home/…/libxml2-2.9.1/python’
make[1]: *** [Makefile:1304: all-recursive] Error 1
make[1]: Leaving directory ‘/home/…/libxml2-2.9.1’
make: *** [Makefile:777: all] Error 2

Solution:
conda install -c anaconda gcc_linux-64