Created attachment 211037 [details] [review]
Link against Foundation framework when libgio uses gnextstepsettingsbackend

I'm building glib-2.32.0 on OS X 10.6 (forcing arch i386), using XCode-4.2. In order to make libraries more able to be dlopen()ed and generally less likely to cause problems for others that would link against them due to missing -l flags, I activate -no-undefined in the makefiles. This leads to:

  CCLD   libgio-2.0.la
Undefined symbols for architecture i386:
  ".objc_class_name_NSString", referenced from:
      pointer-to-literal-objc-class-name in libgio_2_0_la-gnextstepsettingsbackend.o
  ".objc_class_name_NSAutoreleasePool", referenced from:
      pointer-to-literal-objc-class-name in libgio_2_0_la-gnextstepsettingsbackend.o
  ".objc_class_name_NSNumber", referenced from:
      pointer-to-literal-objc-class-name in libgio_2_0_la-gnextstepsettingsbackend.o
  "_objc_msgSend", referenced from:
      _g_nextstep_settings_backend_finalize in libgio_2_0_la-gnextstepsettingsbackend.o
      _g_nextstep_settings_backend_read in libgio_2_0_la-gnextstepsettingsbackend.o
      _g_nextstep_settings_backend_write in libgio_2_0_la-gnextstepsettingsbackend.o
      _g_nextstep_settings_backend_write_tree in libgio_2_0_la-gnextstepsettingsbackend.o
      _g_nextstep_settings_backend_reset in libgio_2_0_la-gnextstepsettingsbackend.o
      _g_nextstep_settings_backend_sync in libgio_2_0_la-gnextstepsettingsbackend.o
      _g_nextstep_settings_backend_init in libgio_2_0_la-gnextstepsettingsbackend.o
      ...
  "_objc_msgSend_fpret", referenced from:
      _g_nextstep_settings_backend_get_g_variant in libgio_2_0_la-gnextstepsettingsbackend.o
  "_objc_enumerationMutation", referenced from:
      _g_nextstep_settings_backend_get_g_variant in libgio_2_0_la-gnextstepsettingsbackend.o
ld: symbol(s) not found for architecture i386
collect2: ld returned 1 exit status
make[4]: *** [libgio-2.0.la] Error 1

./configure is reporting:

checking for Mac OS X Carbon support... yes

which means that gnextstepsettingsbackend.c is built into libgio-2.0.la. That source uses the Foundation framework, but that framework is not linked when building the library. As a result, the symbols that the object uses are not resolvable. Linking against the framework solves the problem for me.

I'm not sure the best place to insert this...attached patch does it in configure.ac as part of the other -framework flag set based on Carbon detection. Could instead go in the Makefile as a conditional item added specifically to libgio_2_0_la_LIBADD or ..._LDFLAGS I guess.