--without-headers and --with-newlib configure options

[booleandomain]

Ian Lance Taylor wrote:
> Normally if you use --with-newlib the compiler will build the gcc
> support library, libgcc, without requiring any external support from the
> C library.  Using --without-headers will disable that, and the gcc
> support library will be built without requiring any library support.
> This disables a few features which are generally uninteresting for
> embedded systems.
> 
> --with-newlib is still useful even when using --without-headers, because
> the newlib header files will be used for libraries other than libgcc,
> such as libstdc++.
> 
> Ian

Let me see if I understood correctly.

--with-newlib tells the compiler to use newlib headers wherever possible 
(also for other libraries than libgcc). --without-headers tells the 
compiler to build libgcc (only it) without any headers at all.

So if I use --without-headers --with-newlib, libgcc will be built 
without requiring the presence of any header, and other libraries will 
be built with newlib headers.

If I use --without-headers alone, libgcc will be built without requiring 
the presence of any headers, and other libraries will be built with libc 
headers.

If I use --with-newlib alone, libgcc and other libraries will be built 
with newlib headers.

If I use nothing, libgcc and other libraries will be built with libc 
headers.

So I think I can use either --without-headers --with-newlib or 
--with-newlib alone for bootstrapping a cross-compiler.