Re: GCC2 merging (was "native language support now available")

[Alexandre Oliva <oliva at dcc dot unicamp dot br>]

John Vickers <jvickers@acorn.com> writes:

> As Alexandre said, egcs hasn't made radical optimisation changes.

Actually, there *have* been radical optimizations: the new alias
analysis code, the haifa scheduler and the global common
sub-expression elimination have all been introduced in egcs, but not
in gcc.  However, none of them has delayed releases, AFAIK.  Which
does not mean they are simple; it's just that they have been
introduced almost atomically.

These were introduced as a large patch, submitted from someone, but I
believe new improvements that might cause long-term instability would
be introduced in egcs as separate branches or as features that can be
enabled by command-line arguments or configure switches, disabled by
default until the feature stabilizes.

This is exactly what is happening within the C++ front-end: the new
name mangling mechanism (-fsquangle), the empty base class
optimization (-fnew-abi) and the std namespace compliance
(-fhonor-std) are all in this stage of development, but they can all
be used in full releases, as long as the user (hacker) knows that they
are not as fully tested as the stable part of the compiler.

-- 
Alexandre Oliva
mailto:oliva@dcc.unicamp.br mailto:aoliva@acm.org
http://www.dcc.unicamp.br/~oliva
Universidade Estadual de Campinas, SP, Brasil