"undefined reference" errors

[Michi <michael monreal gmail com>]

Hi garnome-list,

I have a Garnome install in /opt/gnome2.12 and recently tried to
install some addon software using libs in /opt/gnome2.12/lib - this
works fine for *most* apps. I have set the following environment
variables:

CFLAGS="-O2 -pipe -march=athlon-xp -m3dnow -I/opt/gnome2.12/include/
-L/opt/gnome2.12/lib/"
CPPFLAGS=$CFLAGS
CXXFLAGS=$CFLAGS
ACLOCAL_FLAGS="-I /opt/gnome2.12/share/aclocal -I /usr/share/aclocal"
PATH=$HOME/bin:/opt/gnome2.12/bin:$PATH
LD_LIBRARY_PATH=/opt/gnome2.12/lib:/usr/lib/mozilla
PKG_CONFIG_PATH=/opt/gnome2.12/lib/pkgconfig:/usr/lib/pkgconfig

As said, most apps compile just fine against this setup but I get
"undefined reference" errors when compiling the latest ooo-build or
gnome-screensaver. After investigating a bit It seems that the problem
is the following:

gcc -Wall -Wchar-subscripts -Wmissing-declarations
-Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wcast-align
-Wsign-compare -O2 -pipe -march=athlon-xp -m3dnow
-I/opt/gnome2.12/include/ -Wno-strict-aliasing -Wno-sign-compare -o
gnome-screensaver gnome-screensaver.o gs-monitor.o gs-watcher-x11.o
gs-listener-dbus.o gs-manager.o gs-window-x11.o gs-prefs.o gs-job.o
subprocs.o gs-grab-x11.o dpms.o -Wl,--rpath -Wl,/opt/gnome2.12/lib
-pthread -Wl,--export-dynamic  -L/opt/gnome2.12/lib/
-L/opt/gnome2.12/lib /opt/gnome2.12/lib/libgtk-x11-2.0.so
/opt/gnome2.12/lib/libxml2.so -lz /usr/lib/libdbus-glib-1.so
/usr/lib/libgobject-2.0.so /usr/lib/libglib-2.0.so
/usr/lib/libdbus-1.so -lnsl /opt/gnome2.12/lib/libgconf-2.so
/opt/gnome2.12/lib/libORBit-2.so /opt/gnome2.12/lib/libgmodule-2.0.so
-ldl /usr/lib/libpopt.so /opt/gnome2.12/lib/libgobject-2.0.so
/opt/gnome2.12/lib/libgthread-2.0.so -lpthread
/opt/gnome2.12/lib/libglib-2.0.so -lm -lXss -lXinerama -lXxf86vm
-lXrandr /usr/lib/libXrender.so -L/usr/X11R6/lib -lX11 -lXxf86misc
-Wl,--rpath -Wl,/opt/gnome2.12/lib -Wl,--rpath -Wl,/opt/gnome2.12/lib
/opt/gnome2.12/lib/libgtk-x11-2.0.so: undefined reference to
`g_mapped_file_free'
/opt/gnome2.12/lib/libgtk-x11-2.0.so: undefined reference to
`g_mapped_file_new'/opt/gnome2.12/lib/libgtk-x11-2.0.so: undefined
reference to `g_mapped_file_get_contents'
collect2: ld returned 1 exit status

So there are 3 undefined references to symbols found in
libglib-2.0.so, as shown here:

$ nm /opt/gnome2.12/lib/libglib-2.0.so | grep g_mapped_file_free
000297d0 T g_mapped_file_free
000297d0 t IA__g_mapped_file_free

The relevant line in the Makefile is:

GNOME_SCREENSAVER_LIBS = -Wl,--rpath -Wl,/opt/gnome2.12/lib -pthread
-L/opt/gnome2.12/lib -lgtk-x11-2.0 -lxml2 -lpthread -lz -lm
-ldbus-glib-1 -lgconf-2

So, if I'm interpretating right, -ldbus-glib-1 is pulling in
/usr/lib/libglib-2.0.so as a dependency. Unfortunatly, libglib-2.0.so
as shipped by ubuntu doesn't contain symbols and the build fails:

$ nm /usr/lib/libglib-2.0.so | grep g_mapped_file_free
nm: /usr/lib/libglib-2.0.so: no symbols

Editing the Makefile to

GNOME_SCREENSAVER_LIBS = -Wl,--rpath -Wl,/opt/gnome2.12/lib -pthread
-L/opt/gnome2.12/lib -lgtk-x11-2.0 -lxml2 -lpthread -lz -lm -lgconf-2
-ldbus-glib-1

solves the problem, I guess installing dbus to /opt/gnome2.12 would do
so, too, but this would mean I was forced to always be in sync with
the ubuntu version, as replacing the dbus deamon is a no-no.

Does anyone have an idea how I can solve this mess? Is there a way to
tell the system not to use libs from a given directory? Naturally I
need most libs tom /usr/lib, but I don't want those used that I also
have in my Garnome install...

Thx,
Michi