Re: [AD] fix for universal mac build on PPC

["Dave Vasilevsky" <djvasi@xxxxxxxxxx>]

On 1/5/07, Matthew Leverton <meffer@xxxxxxxxxx> wrote:
> The following switch is added to the various UB flags:
> -isysroot /Developer/SDKs/MacOSX10.4u.sdk

Don't forget to also add
-Wl,-syslibroot,/Developer/SDKs/MacOSX10.4u.sdk to the linking flags,
to make sure we link against the proper libs.

> I believe this means that the universal build will require a minimum
> of OS X 10.4 for both PPC and Intel. However, I'm not sure if there is
> any clean way around that without coming up with a brand new build
> system. From my (limited) understanding, in order to target different
> versions of OS X for the PPC and Intel builds within a makefile, you'd
> have to build the project twice and then use "lipo" to combine both
> binaries into one.

Yes, this would be the better way to do things, but it looks difficult
using your build system. There is one kinda hacky way around this:
write a short shell (or perl) script as a wrapper for gcc. Then if we
set CC = $WRAPPER in the Makefile, our wrapper could turn

$CC -arch ppc -arch i386  $FLAGS -o foo.o ...

into

$REAL_CC_PPC -arch ppc $FLAGS $PPC_FLAGS -o foo.o.ppc ...
$REAL_CC_I386 -arch i386 $FLAGS $I386_FLAGS -o foo.o.i386 ...
lipo foo.o.ppc foo.o.i386 -create -output foo.o

Like I said, quite hacky but it ought to work. If we do not do this,
all the 10.3 users will be left out in the cold if we distribute
universal builds.

Dave