🚀 go-pugleaf

In article <9301242117.AA04053@cs.rice.edu> dougm@cs.rice.edu (Doug Moore) writes:
>The program that follows demonstrates (I think) that under some
>circumstances, g++ destroys a temporary prematurely.  The ARM is a bit
>too vague to let me say with complete confidence that this is a bug,
>but it certainly ought to be.

The g++ behavior (early destruction of temporaries) is legal according to
the ARM.  This is partly because the ARM is so permissive on this subject.
See the gnu.g++.help FAQ; also, you might take a look at recent discussion
on comp.std.c++ about what the ANSI C++ committee is doing about the
destruction of temporaries issue (they are still debating it).

Sun C++ is a port of cfront, which destroys temporaries very late (at
the end of the containing scope).  If you write a program that depends on
this behavior, you have written a non-portable program, and you'll have
problems on other compilers as well.

It appears that eventually ANSI will mandate that temporaries live
longer than they do now, but not (necessarily) as long as they do in
cfront.  When that happens, you can expect the g++ maintainers to
conform.

See the FAQ for some suggestions on how to work around problems caused
by this.  Basically, you can give the temporary a name (by using it
to initialize a reference), guaranteeing that it will live until the
end of scope of that name.


--
Joe Buck	jbuck@ohm.berkeley.edu