Error during building stage 2 gcc-9.2.0: "configure: error: cannot compute sizeof (long long)

[Jonathan Wakely]

On Sun, 5 Jan 2020 at 12:46, Xi Ruoyao wrote:
>
> On 2020-01-05 12:19 +0000, Winston Smith wrote:
> > > Winston Smith schrieb:
> > > > Hi All,
> > > >
> > > >
> > > > I've trying to build gcc-9.2.0 on a host with gcc-4.5.1, matching
> > > > versions of mpfr, gmp and mpc are symlinked into the top-level of the
> > > > tree.
> > > >
> > > >
> > > > This is my configure:
> > > >
> > > >
> > > > $ mkdir build
> > > >
> > > > $ cd build
> > > >
> > > > $ ../configure --prefix=/tmp/chroot-gcc/usr/ --enable-bootstrap
> > > > --with-glibc-version=2.12 --with-newlib --without-headers --disable-nls
> > > > --disable-shared --disable-multilib --disable-decimal-float
> > > > --disable-threads --disable-libatomic --disable-libgomp
> > > > --disable-libquadmath
> > > >   --disable-libssp --disable-libvtv --disable-libstdcxx
> > > > --enable-languages=c,c++
>
> With --disable-libstdcxx you can't bootstrap gcc, because stage 2 gcc has to
> link to stage 1 libstdc++.

Right. If you just want to build the compiler front-ends without the
runtime libs then don't try to do a 3-stage bootstrap, just configure
then run 'make all-gcc' to build just the stage1 compilers, and then
'make install-gcc'.

If you're trying to build a 3-stage bootstrap of the whole of GCC
including runtime libraries, you need to build libstdc++.

Maybe it would help if you explain what you're trying to achieve with
this configure command.