py27-gobject3 fails to build on MacOS 10.5.8 PPC; can fix problem with -fPIC

[paulccobb@…]

I found a few days ago that in trying to upgrade py27-gobject3 from 3.12.1_0 to 3.14.0_0, the build failed with the following error in main.log:

ld: absolute addressing (perhaps -mdynamic-no-pic) used in _pygobject_constructv from .libs/_gi_la-gobjectmodule.o not allowed in slidable image. Use '-read_only_relocs suppress' to enable text relocs
collect2: ld returned 1 exit status

I can't claim to be an expert on MacPorts or on PowerPC build issues, but I've tried to understand what's going wrong, and offer the following info in case it helps.

I found by experiment in the work/pygobject-3.14.0 directory (under macports/build) that if I insert the switch '-fPIC' in the CFLAGS for each Makefile, that makes the problem go away. As far as I understand the issue, PowerPC compilation has historically assumed -mdynamic_no_pic as the default; so if the rest of the build process wants pic, it has to be enabled explicitly.

In case they're useful, I've attached two files that each capture the output of a 'make' run, invoked in the work/pygobject-3.14.0 directory without args: the first one ends with the build error, while the second has the -fPIC switch present in all Makefiles and appears to run to completion.

[paulccobb@…]

First file: make output log showing build error

[paulccobb@…]

Second file: make output log, showing presence of '-fPIC' option, build error apparently gone

[mf2k (Frank Schima)]

In the future, please use WikiFormatting, fill in the Port field and Cc the port maintainers (port info --maintainers py27-gobject3), if any.

[neverpanic (Clemens Lang)]

Patch against the Portfile that attempts to fix this issue

[neverpanic (Clemens Lang)]

I've attached a patch against the Portfile. Can you test whether this fixes the issue for you? Unfortunately, I don't have a PowerPC box ready to test this myself.

[neverpanic (Clemens Lang)]

Sorry that patch has a syntax error, this one is the right one:

Portfile

@@ -48 +48 @@
                             --disable-silent-rules
     configure.cppflags-append \
                             -I${python.prefix}/include
+    platform darwin {
+        # PowerPC builds fail because -mdynamic_no_pic is the default, #46943
+        if {([variant_isset universal] && ("ppc" in ${universal_archs} || "ppc64" in ${universal_archs}))
+            || (![variant_isset universal] && [string match "ppc*" ${build_arch}])} {
+                configure.cflags-append -fPIC
+        }
+    }
 
     build.cmd               [portbuild::build_getmaketype]
     build.target

[neverpanic (Clemens Lang)]

Closing due to missing response. Please re-open if you can confirm this fixes your issue.