[MacPorts] #21261: Can't unset -arch x86_64 in portfile in Snow Leopard

[MacPorts]

#21261: Can't unset -arch x86_64 in portfile in Snow Leopard
----------------------------------------------------------+-----------------
 Reporter:  njbutko@…                                     |       Owner:  macports-tickets@…                   
     Type:  defect                                        |      Status:  new                                  
 Priority:  Normal                                        |   Milestone:                                       
Component:  ports                                         |     Version:  1.8.0                                
 Keywords:  snow leopard, build_arch, arch, x86_64, i386  |        Port:                                       
----------------------------------------------------------+-----------------
 I'm trying to create a -arch i386 variant of a port, but as far as I can
 tell from the Guide and all my valiant attempts, there's no way to delete
 -arch x86_64 from the make flags.

 My variant looks something like

 {{{
 variant SL_32bit description {Build in 32-bit mode on Snow Leopard.} {
         configure.args-delete "-arch x86_64"
         configure.cxxflags-append "-arch i386"
 }
 }}}

 which leads to the following output:

 {{{
  /usr/bin/g++-4.2 -DHAVE_CONFIG_H -I. -I. -I../.. -I.
 -I../../cxcore/include -I../.. -DNDEBUG -I/opt/local/include -Wall -fno-
 rtti -pipe -O3 -g -march=prescott -ffast-math -fomit-frame-pointer -O2
 -I/opt/local/include -L/opt/local/lib -arch i386 -arch x86_64 -MT
 cxalloc.lo -MD -MP -MF .deps/cxalloc.Tpo -c cxalloc.cpp  -fno-common -DPIC
 -o .libs/cxalloc.o
 g++-4.2: -E, -S, -save-temps and -M options are not allowed with multiple
 -arch flags
 }}}

 where the bug is "-arch i386 -arch x86_64". I have tried deleting from
 every known configure and build flag in the guide, and none of them works.

 That the "-arch x86_64" is there at all seems amiss. I do not have
 build_arch set in macports.conf, and g++ builds in 64-bit mode by default
 in Snow Leopard, so at best it is redundant. I don't want to set
 "build_arch" in macports.conf because it is not needed for all ports, and
 breaks many of them. I simply want to turn it on in this variant in this
 portfile. In searching the documentation and other tickets, I can't find a
 good answer for how to do so.

 The portfile in question never touches build_arch or sets -arch (except
 for my variant):

 {{{
 # $Id: Portfile 50984 2009-05-14 21:08:43Z and.damore at macports.org $

 PortSystem                      1.0

 name                            opencv
 version                         1.0.0
 categories                      graphics science
 platforms                       darwin
 maintainers                     gmail.com:stante
 description                     Intel(R) Open Source Computer Vision
 Library
 long_description        opencv is a library that is mainly aimed at real
 time \
                                         computer vision. Some example
 areas would be \
                                         Human-Computer Interaction (HCI),
 Object Identification, \
                                         Segmentation and Recognition, Face
 Recognition, Gesture \
                                         Recognition, Motion Tracking, Ego
 Motion, Motion \
                                         Understanding, Structure From
 Motion (SFM), and Mobile \
                                         Robotics.

 homepage
 http://www.intel.com/technology/computing/opencv/
 master_sites            sourceforge:opencvlibrary
 checksums                       md5 146a05005f2d2c16c4ee10ebd7f1dd58

 depends_lib                     port:gtk2 port:zlib port:jpeg \
                                         port:libpng port:tiff

 configure.env           CPATH="${prefix}/include"    \
                                         LIBRARY_PATH="${prefix}/lib"
 configure.cxxflags-append       "-I${prefix}/include -L${prefix}/lib"
 }}}

-- 
Ticket URL: <http://trac.macports.org/ticket/21261>
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