This is a followup to the following gtk-devel-list thread:
  http://mail.gnome.org/archives/gtk-devel-list/2004-February/msg00127.html

I've filed it as a GTK bug, but it also affects ATK, Pango and Glib.

Currently, the restriction on export of underscore prefixed symbols is not
functioning correctly on Linux, even when libtool has a working
-export-symbols implementation (ie. 1.5.2 or older versions with the
expsym-linux patch).

This problem seems to be that the linker ignores the -version-script option
when it also sees --export-dynamic.  The flags output by "pkg-config --libs
gmodule-2.0" include -Wl,--export-dynamic so libtool will pass the flag
through without checking it.

Unless I am mistaken, there isn't any case where you would need to use
--export-dynamic when linking a shared library.  Its usual purpose is to
export the symbols from a normal executable.  Since this is done by default
for a shared library it shouldn't be needed, and in fact seems to be
harmful in this case.

The solution to the problem is to remove the flag from the link line.  I
posted a simplistic patch to gtk-devel-list to do this (will attach it to
this bug report shortly), but the eventual fix might be to remove the flag
from gmodule-2.0's libs list.