Re: Compiling as 32bit on MacOSX
In article <8hpgn7fho...@mid.individual.net>, Gregory Ewing wrote: > Ned Deily wrote: > > Perhaps you're > > calling ld(1) directly? To link multiple-arch executables (etc), the > > Apple gcc driver does the dirty work of calling ld multiple times and > > lipo-ing the results. > > Is this something that only works at link time, then? The > gcc man page says: > >"Multiple options work, and >direct the compiler to produce "universal" binaries including >object code for each architecture specified with -arch." > > From this I was hoping to be able to do > > gcc -arch i386 -arch x86_64 -c foo.c > > and get dual-architecture .o files that could then be linked > into dual-architecture libraries. But if I do the above, I > just get an x86_64 .o file. > > Are you saying that I need to compile separate sets of .o > files and then combine them at link time? That sounds like > an awkward thing to retrofit onto a library's existing > build system. No, it's supported both at compile and link time. Here's a compile on 10.6: $ /usr/bin/gcc --version i686-apple-darwin10-gcc-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5664) Copyright (C) 2007 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ /usr/bin/gcc -arch i386 -arch x86_64 -c foo.c $ file foo.o foo.o: Mach-O universal binary with 2 architectures foo.o (for architecture i386): Mach-O object i386 foo.o (for architecture x86_64): Mach-O 64-bit object x86_64 BTW, if, for some reason, you *do* need to extract a particular architecture from a multi-arch file, you can use lipo to do it: $ lipo foo.o -output foo_32.o -extract i386 $ lipo foo.o -output foo_64.o -extract x86_64 $ file foo_32.o foo_32.o: Mach-O universal binary with 1 architecture foo_32.o (for architecture i386): Mach-O object i386 $ file foo_64.o foo_64.o: Mach-O universal binary with 1 architecture foo_64.o (for architecture x86_64): Mach-O 64-bit object x86_64 -- Ned Deily, n...@acm.org -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
Ned Deily wrote: Perhaps you're calling ld(1) directly? To link multiple-arch executables (etc), the Apple gcc driver does the dirty work of calling ld multiple times and lipo-ing the results. Is this something that only works at link time, then? The gcc man page says: "Multiple options work, and direct the compiler to produce "universal" binaries including object code for each architecture specified with -arch." From this I was hoping to be able to do gcc -arch i386 -arch x86_64 -c foo.c and get dual-architecture .o files that could then be linked into dual-architecture libraries. But if I do the above, I just get an x86_64 .o file. Are you saying that I need to compile separate sets of .o files and then combine them at link time? That sounds like an awkward thing to retrofit onto a library's existing build system. -- Greg -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
In article <8hmpchfsh...@mid.individual.net>, Gregory Ewing wrote: > Ned Deily wrote: > > You'll also need to specify the appropriate SDK using Apple's gcc > > -sysroot option. > Are you sure? I'm not asking for ppc + i386, I'm > asking for i386 + x86_64. I can get either of these > individually without switching SDKs. Well, you'd need it if you want backward compatibility (with an older ABI) but, no, you wouldn't need -sysroot just to produce i386 and x86_64 on a 64-bit capable machine running 10.6. Getting back to your previous post: "But I can't seem to get it to work -- it just uses the last architecture specified." Perhaps you're calling ld(1) directly? To link multiple-arch executables (etc), the Apple gcc driver does the dirty work of calling ld multiple times and lipo-ing the results. See the Apple ld(1) man page. -- Ned Deily, n...@acm.org -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
Ned Deily wrote: You'll also need to specify the appropriate SDK using Apple's gcc -sysroot option. Are you sure? I'm not asking for ppc + i386, I'm asking for i386 + x86_64. I can get either of these individually without switching SDKs. -- Greg -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
On Oct 13, 2010, at 3:54 AM, Gregory Ewing wrote: > Philip Semanchuk wrote: > >> Hi Greg, >> Are you talking about compiling Python itself or extensions? > > I've managed to get Python itself compiled as 32 bit, > and that also seems to take care of extensions built > using 'python setup.py ...'. > > I'm mainly concerned about non-Python libraries that > get wrapped by the extensions, of which I've built up > quite a collection over the years. Currently I'm having > to keep a careful eye out when building them to make > sure they don't get compiled with the wrong architecture, > since gcc's natural inclination is to default to 64 bit > whenever it's available. > > So I was wondering if there was some way of globally > changing that default that doesn't rely on compiler > options getting passed correctly through the many and > varied layers of build technology that one comes across. > But from what I've seen so far, it seems not. If CFLAGS isn't doing the trick for you, then I don't know what to suggest. Maybe some libs also need LDFLAGS='-arch i386 -arch x86_64'? FYI, the `file` command will give you information about whether or not a binary is 32-bit, 64-bit or both. $ file shlib/libreadline.6.1.dylib shlib/libreadline.6.1.dylib: Mach-O universal binary with 2 architectures shlib/libreadline.6.1.dylib (for architecture i386):Mach-O dynamically linked shared library i386 shlib/libreadline.6.1.dylib (for architecture x86_64): Mach-O 64-bit dynamically linked shared library x86_64 Good luck Philip -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
In article <8hl75sf6j...@mid.individual.net>, Gregory Ewing wrote: > On a related note, according to the man page for Apple's > gcc, you're supposed to be able to use both '-arch i386' > and '-arch x86_64' at the same time and get fat binaries. > That would actually be my preferred option, because then > I wouldn't have to go back and rebuild all my libraries > if I decide to switch to 64 bit in the future. > > But I can't seem to get it to work -- it just uses the > last architecture specified. Has anyone successfully done > this? Is there some trick to it that I've missed? You'll also need to specify the appropriate SDK using Apple's gcc -sysroot option. -- Ned Deily, n...@acm.org -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
Gregory Ewing writes: > Philip Semanchuk wrote: > >> Hi Greg, >> Are you talking about compiling Python itself or extensions? > > I've managed to get Python itself compiled as 32 bit, > and that also seems to take care of extensions built > using 'python setup.py ...'. > > I'm mainly concerned about non-Python libraries that > get wrapped by the extensions, of which I've built up > quite a collection over the years. Currently I'm having > to keep a careful eye out when building them to make > sure they don't get compiled with the wrong architecture, > since gcc's natural inclination is to default to 64 bit > whenever it's available. > > So I was wondering if there was some way of globally > changing that default that doesn't rely on compiler > options getting passed correctly through the many and > varied layers of build technology that one comes across. > But from what I've seen so far, it seems not. If all you have is a fat-binary, you can still work with that using the lipo-tool to remove those architectures you are not interested in. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
Jason Swails wrote: Try setting the compiler itself as "gcc -m32" You mean by setting CC? That's a cunning plan -- I'll give it a try. On a related note, according to the man page for Apple's gcc, you're supposed to be able to use both '-arch i386' and '-arch x86_64' at the same time and get fat binaries. That would actually be my preferred option, because then I wouldn't have to go back and rebuild all my libraries if I decide to switch to 64 bit in the future. But I can't seem to get it to work -- it just uses the last architecture specified. Has anyone successfully done this? Is there some trick to it that I've missed? -- Greg -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
Philip Semanchuk wrote: Hi Greg, Are you talking about compiling Python itself or extensions? I've managed to get Python itself compiled as 32 bit, and that also seems to take care of extensions built using 'python setup.py ...'. I'm mainly concerned about non-Python libraries that get wrapped by the extensions, of which I've built up quite a collection over the years. Currently I'm having to keep a careful eye out when building them to make sure they don't get compiled with the wrong architecture, since gcc's natural inclination is to default to 64 bit whenever it's available. So I was wondering if there was some way of globally changing that default that doesn't rely on compiler options getting passed correctly through the many and varied layers of build technology that one comes across. But from what I've seen so far, it seems not. -- Greg -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
On Oct 12, 2010, at 8:29 PM, Gregory Ewing wrote: > I'm getting my Python environment set up on a new > Snow Leopard machine, and I'd like to compile everything > in 32 bit mode for the time being, because some of the > extensions I need use APIs that aren't available in > 64 bit. > > Is there some environment variable or config setting > that will make gcc compile 32 bit binaries by default? > Setting CFLAGS isn't very reliable, since the build > systems of some libraries don't seem to take notice > of it. Hi Greg, Are you talking about compiling Python itself or extensions? -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
In article <8hkct2f31...@mid.individual.net>,
Gregory Ewing wrote:
> I'm getting my Python environment set up on a new
> Snow Leopard machine, and I'd like to compile everything
> in 32 bit mode for the time being, because some of the
> extensions I need use APIs that aren't available in
> 64 bit.
>
> Is there some environment variable or config setting
> that will make gcc compile 32 bit binaries by default?
> Setting CFLAGS isn't very reliable, since the build
> systems of some libraries don't seem to take notice
> of it.
It varies. Projects that use one of the Apple-supplied gcc's (4.2 or
4.0) generally use the -arch parameter.
For Python itself on 10.6, there isn't a standard configure option to
build just for i386 (Intel 32-bit). The two easiest choices are to
either build for 32-bit only which results in a i386 and ppc universal
build:
./configure MACOSX_DEPLOYMENT_TARGET=10.6
--with-universal-archs="32-bit"
--enable-universalsdk=/Developer/SDKs/MacOSX10.6.sdk
or tweak the configure options a bit which *should* result in an
i386-only build (at least for 2.7 and 3.2):
./configure MACOSX_DEPLOYMENT_TARGET=10.6 CFLAGS="-arch i386"
LDFLAGS="-arch i386"
If you want backwards compatibility, add or change the sdk and
deployment target values ("10.5" "MacOSX10.5.sdk" or "10.4"
"MacOSX10.4u.sdk" along with GCC=/usr/bin/gcc-4.0). For a framework
build, throw in --enable-framework.
Distutils should ensure that the right settings will get passed on to
any extension module builds.
--
Ned Deily,
n...@acm.org
--
http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
On 13/10/2010 01:29, Gregory Ewing wrote: I'm getting my Python environment set up on a new Snow Leopard machine, and I'd like to compile everything in 32 bit mode for the time being, because some of the extensions I need use APIs that aren't available in 64 bit. Is there some environment variable or config setting that will make gcc compile 32 bit binaries by default? Setting CFLAGS isn't very reliable, since the build systems of some libraries don't seem to take notice of it. Not MacOSX, but might help: http://www.cyberciti.biz/tips/compile-32bit-application-using-gcc-64-bit-linux.html -- http://mail.python.org/mailman/listinfo/python-list
Re: Compiling as 32bit on MacOSX
Try setting the compiler itself as "gcc -m32" -- Jason Swails Quantum Theory Project, University of Florida Ph.D. Graduate Student 352-392-4032 On Oct 12, 2010, at 8:29 PM, Gregory Ewing wrote: > I'm getting my Python environment set up on a new > Snow Leopard machine, and I'd like to compile everything > in 32 bit mode for the time being, because some of the > extensions I need use APIs that aren't available in > 64 bit. > > Is there some environment variable or config setting > that will make gcc compile 32 bit binaries by default? > Setting CFLAGS isn't very reliable, since the build > systems of some libraries don't seem to take notice > of it. > > -- > Greg > -- > http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Compiling as 32bit on MacOSX
I'm getting my Python environment set up on a new Snow Leopard machine, and I'd like to compile everything in 32 bit mode for the time being, because some of the extensions I need use APIs that aren't available in 64 bit. Is there some environment variable or config setting that will make gcc compile 32 bit binaries by default? Setting CFLAGS isn't very reliable, since the build systems of some libraries don't seem to take notice of it. -- Greg -- http://mail.python.org/mailman/listinfo/python-list
