Status and rationale for toplevel bootstrap (was Re: Example of debugging GCC with toplevel bootstrap)

[Joe Buck]

I wrote:
> For a native compiler, the bootstrap process guarantees (and even
> partially tests) that, regardless of the original compiler, the object
> code of generated compiler itself is byte-for-byte identical regardless of
> which compiler we started with.  Since the compiler itself is identical,
> then of course the results are identical.

As has been pointed out, there are exceptions to this (bits per long long,
etc).