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Re: alloca again



On Tue, Oct 04, 2022 at 02:22:23AM +0000, David Holland wrote:
> On Tue, Oct 04, 2022 at 12:41:07AM +0300, Valery Ushakov wrote:
>  > On Mon, Oct 03, 2022 at 18:32:47 +0000, David Holland wrote:
>  > 
>  > > On Mon, Oct 03, 2022 at 03:45:06PM +0200, Roland Illig wrote:
>  > >  > > This is the current alloca definition in the libc headers:
>  > >  > > 
>  > >  > > #if defined(_NETBSD_SOURCE)
>  > >  > > #if defined(alloca) && (alloca == __builtin_alloca) && \
>  > > 
>  > > Note that the part you didn't quote is
>  > >    defined(__GNUC__) && __GNUC__ < 2
>  > > and all it does is change the argument type to int from size_t.
>  > > 
>  > > This makes it highly unlikely that it ever failed, for an assortment
>  > > of reasons, not the least of which is that we removed critical parts
>  > > of gcc2 support from /usr/include years ago so it's not been exercised
>  > > in at least that long.
>  > 
>  > ITYM gcc1?  Note "less than" in  __GNUC__ < 2
> 
> Oops! Yeah.
> 
> Was gcc1 still in use even in 1993? I can't remember.

Yes, because gcc2 was unstable for many architectures, and had performance
regressions for others.

-- 
 Thor Lancelot Simon	                                     tls%panix.com@localhost
    "Somehow it works like a joke, but it makes no sense."
                                                    --Gilbert Gottfried


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