make compiled a lot of programs, but not gcc

[Marco Sulla <gnu dot org at marco dot sulla dot e4ward dot com>]

Hello all. I have a problem compiling gcc 9.2.0 on my machine.

TL;DR
After the make, I have a lot of programs in `gcc` subdir, like `xgcc`,
`cpp`, `gfortran` etc, but *not* gcc. What I did wrong?


Long explanation. I:
1. downloaded the tar of gcc 9.2.0 from the official size
2. extracted it in a `gcc` subdir
3. created at the same level a `gcc_build` dir
4. installed texinfo, dejagnu, bison, flex and gawk
5. in bash:

./gcc/contrib/download_prerequisites
mkdir gcc_build
cd gcc_build
../gcc/configure --program-suffix -9.2.0
make

I have Lubuntu 18.04.3 as guest on a Windows 7 host, machine HP
ProBook 650 G2 (not my laptop...)

PS: `configure` gave me also this warning:

> *** This configuration is not supported in the following subdirectories:
>
> gnattools gotools target-libada target-libhsail-rt target-libphobos target-zlib target-libgo target-libffi target-liboffloadmic
>
> (Any other directories should still work fine.)

I'm concerned about zlib and libffi. Does this warning means gcc can't
support zip and libffi?

Thank you in advance.