[MacPorts] #64229: python27 +universal fails to build for ppc+ppc64 on 10.5.8

[MacPorts]

#64229: python27 +universal fails to build for ppc+ppc64 on 10.5.8
---------------------------+-------------------------------------
  Reporter:  barracuda156  |      Owner:  (none)
      Type:  defect        |     Status:  closed
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.7.1
Resolution:  duplicate     |   Keywords:  PowerPC, Leopard, ppc64
      Port:  python27      |
---------------------------+-------------------------------------

Comment (by kencu):

 Replying to [comment:17 barracuda156]:

 > So that’s why Macports passes -arch ppc when building anything on 10.6.

 That's not exactly it. MacPorts passes -arch ppc when building on 10.6 for
 ppc because the compiler supports it and so macports adds the archflags to
 build CXXFLAGS, LDFLAGS, and CFLAGS during it's port configure setup. If
 you find a file called "portconfigure.tcl" you will see all the logic and
 functions used in there.

 It knows to pass "ppc" specifically because you set this, in
 macports.conf:
 {{{
 build_arch              ppc
 }}}

 MacPorts doesn't actually know anything about what is in libSystem.B.dylib
 at this point.

 The person who told you they were successfully building +universal
 (presuming that meant ppc and ppc64) on 10.6-for-PPC was just mistaken.

 \\


 > (Sorry if a silly question, but simply replacing the dylib won’t solve
 the issue, right?)

 You can't just take the one from 10.5.8 and sub it in to 10.6-for-PPC, if
 that is what you mean -- the 10.6-for-PPC system is built against symbols
 in that 10.6 libSystem.B.dylib and many of these are not going to be in
 10.5.8 (if they were -- just stay on 10.5.8 :> -- which is what I have
 been recommending to you anyway, as 10.6-for-PPC strikes me as a total
 waste of time.)

 To actually make ppc64 work on 10.6-for-PPC you would have to go through
 all the system components (not just libSystem.B.dylib, but every library)
 find the correct version of the source code (almost impossible) and add a
 build arch of ppc64 to however they build it originally. This is really
 going to be hard. These system components are built in different ways,
 some with Xcode, some with an interesting custom build system used
 internally in Apple that we can see glimpses of in our apple-gcc-4.2,
 cctools, ld64, and libmacho ports.

 And then once you go actually go through the who-knows-how-many fixes
 needed to get 64bit PowerPC building, you'd have to start seeing what bugs
 there are, etc.

 I can't see anyone doing this, but .

-- 
Ticket URL: <https://trac.macports.org/ticket/64229#comment:18>
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