> On Dec 17, 2017, at 12:02 AM, Jeremy Huddleston Sequoia <jerem...@apple.com>
> wrote:
>
>
>
>> On Dec 6, 2017, at 20:09, Ken Cunningham <ken.cunningham.web...@gmail.com>
>> wrote:
>>
>>
>>> On 2017-12-06, at 12:19 PM, Ken Cunningham wrote:
>>>
>>> There have been a number of tickets over the past two years that relate to
>>> compiler selection on PPC systems.
>>>
>>> Basically, on PPC, if the default compiler (gcc 4.2 on 10.5, or apple-gcc42
>>> on Tiger) does not work to build a port, the only other compiler that
>>> should be then used is gcc6. Maybe someday this might be gcc7, if we fix up
>>> the extra errors found in gcc7.
>>>
>>> Presently, however, PPC systems go down the same compiler selection path as
>>> Intel systems. That usually leads to clang 3.3 or clang 3.4 being selected,
>>> and this always fails miserably on PPC.
>>>
>>> Finally, there are a number of ports that blacklist all gcc compilers like
>>> this *gcc* . This is often appropriate for Intel systems, but completely
>>> wrong for PPC. So I don't know if it is possible to clear or ignore that
>>> setting in a Portfile -- probably not, but when I set the default_compiler
>>> in macports.conf, it does appear override that setting, so maybe it is
>>> possible.
>>>
>>> Thanks,
>>>
>>> Ken
>>
>>
>> I think the part of code that would need fixing is in portconfigure.tcl, in
>> this block:
>>
>> # Legacy cases
>> if {[vercmp $xcodeversion 4.0] < 0} {
>> if {[vercmp $xcodeversion 3.2] >= 0} {
>> if {[string match *10.4u* ${configure.sdkroot}]} {
>> return {gcc-4.0}
>> }
>> } elseif {[vercmp $xcodeversion 3.0] >= 0} {
>> return {gcc-4.2 apple-gcc-4.2 gcc-4.0 macports-clang-3.4
>> macports-clang-3.3}
>> } else {
>> return {apple-gcc-4.2 gcc-4.0 gcc-3.3 macports-clang-3.3}
>> }
>> }
>>
>>
>> ===================
>>
>> if I were to put in an appropriate PPC build arch test there, and change the
>> returned compilers for ppc to return something like the following, we should
>> be OK. Just have to figure out the right kind of build.arch test to use in
>> portconfigure.tcl:
>>
>> } elseif {[vercmp $xcodeversion 3.0] >= 0} {
>> return {gcc-4.2 apple-gcc-4.2 gcc-4.0 macports-gcc-6}
>> } else {
>> return {apple-gcc-4.2 gcc-4.0 macports-gcc-6}
>
> macports-gcc-6 is also not capable of building fat binaries, so +universal
> won't work with it. If you're interested, you can maybe take the gcc
> driver-driver out of apple-gcc-4.2 (or llvm-gcc-4.2) and update it to work
> for macports-gcc.
Thanks for the comments.
It would be neat if we could build a multi-arch cross-compiling gcc6 or gcc7
again, but a niche product to be sure.
The driver-driver.c work has been done by others to allow it to work with
gcc4.6 to gcc4.9, so shouldn't be too hard to move that up to gcc6/7.
K
