fltk make error on Ubuntu. bits/statx-generic.h: No such file or directory

Question

I am trying to install the fltk library:

./configure --enable-shared --enable-threads --enable-debug
make 

The make command gives the following errors:

=== making src ===
Compiling Fl.cxx...
In file included from /usr/include/x86_64-linux-gnu/sys/stat.h:446,
                 from ../FL/fl_utf8.h:62,
                 from ../FL/Fl.H:32,
                 from Fl.cxx:64:
/usr/lib/gcc/x86_64-linux-gnu/9/include-fixed/bits/statx.h:38:25: error: missing binary operator before token "("
   38 | #if __glibc_has_include ("__linux__/stat.h")
      |                         ^
/usr/lib/gcc/x86_64-linux-gnu/9/include-fixed/bits/statx.h:46:10: fatal error: bits/statx-generic.h: File o directory non esistente
   46 | #include <bits/statx-generic.h>
      |          ^~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
make[1]: *** [../makeinclude:162: Fl.o] Error 1
make: *** [Makefile:24: all] Error 1

I am using Ubuntu 19.04 and gcc 9.2.1. I am a beginner, any help would be appreciated!