os.major etc. on Linux

[Ryan Schmidt]

On May 13, 2016, at 3:07 AM, René J.V. Bertin wrote:

> On Friday May 13 2016 15:21:53 Joshua Root wrote:
> 
>>>> Side-ways related: why is os_arch reset to i386 from x86_64 on line 636? >From what I've seen that causes packages to be labelled and registered as i386 (i.e. 32bit) when built on 64bit linux.
>>> 
>>> In MacPorts, os_arch is i386 on all Intel Macs (32-bit and 64-bit), and ppc on all PowerPC Macs (32-bit and 64-bit). Changing that now would break all ports that rely on the existing long-standing behavior.
> 
> I was just asking why, apparently that's a historic choice that was made when 64-bit Intel Macs weren't on the horizon yet?

os_arch is the way ports and probably MacPorts base differentiates an Intel computer from a PowerPC computer. It is not a mechanism to determine the bitness; if you need to determine bitness, use other methods, such as build_arch and universal_archs. build_arch and universal_arch determines how a package is registered when installed; os_arch doesn't enter into it, as far as I know.

> Either way, I am NOT proposing to change it for the Darwin platform. If it's OK to consider a fix for the OS version issue it might possibly also be OK to consider handling os_arch (os.arch) differently on that platform, i.e.
> 
> {{{
>    if {${os_platform} eq "linux"} {
>        if {$os_arch eq {i586} || $os_arch eq {i686}} {set os_arch "i386"}
>    } else {
>        if {$os_arch eq "i586" || $os_arch eq "i686" || $os_arch eq "x86_64"} {set os_arch "i386"}
>    }
> }}}
> 
>> This corresponds to `uname -p` BTW.
> 
> I don't have access to my Mac right now, but on Linux/64-bit that command says x86_64 . Is that what $tcl_platform(machine) does/contains?
> 
> If memory serves me well, setting os_arch to i386 on 64-bit Linux led to frequent if not continuous requests to install port dependencies (because somewhere they were considered available only as 32-bit) which were then satisfied immediately because the ports were in fact already installed.
> 
> I'm curious though, what ports rely on i386 meaning "Intel, 32 or 64 bit" rather than "Intel, 32 bit", directly in their Portfile rather than indirectly through "base"? I find that confusing and it often makes me pause when I see the term appear in the log of a build I know should be for 64-bit (and it feels to me to be as smart as using an undocumented feature ;)).

Ports use os_arch indirectly when they contain a "platform i386" or "platform powerpc" block.