Error building sage packages ppl and brial

[Daniel Lima]

Hi, I'm having problems building Sagemath 9.6 in my Ubuntu 20.04 CPU = Intel® Core™ i7-7500U CPU @ 2.70GHz × 4. After running ./configure and make I get the following error 

Error building Sage.

The following package(s) may have failed to build (not necessarily
during this run of 'make all-start'):

* package:         brial-1.2.8
  last build time: jun 9 15:07
  log file:        /home/daniel/sage/logs/pkgs/brial-1.2.8.log
  build directory: /home/daniel/sage/local/var/tmp/sage/build/brial-1.2.8

* package:         ppl-1.2.p1
  last build time: jun 9 15:17
  log file:        /home/daniel/sage/logs/pkgs/ppl-1.2.p1.log
  build directory: /home/daniel/sage/local/var/tmp/sage/build/ppl-1.2.p1

It is safe to delete any log files and build directories, but they
contain information that is helpful for debugging build problems.
WARNING: If you now run 'make' again, the build directory of the
same version of the package will, by default, be deleted. Set the
environment variable SAGE_KEEP_BUILT_SPKGS=yes to prevent this.

make[1]: *** [Makefile:39: all-start] Erro 1
make[1]: Saindo do diretório '/home/daniel/sage'
make: *** [Makefile:13: all] Erro 2