using GNU libc 2.27

[Paul Zimmermann]

thank you Arsen.

For the record I was able to solve my issue with the help of Vincent:

    (You might have to configure GMP and MPFR with --sysroot=$ROOT in CFLAGS,
    where $ROOT/usr/{include,lib} contain GNU libc 2.27 include/lib files.)

Then I had to fix manually two places where include files from GNU libc 2.27
were hardcoded in <linux/xxx.h>, changing to <xxx.h> did the trick.

Paul