[tests/tools] Don't install libdisable-npots.so

The libdisable-npots library is just used as a helper as part of
make test so it should not be installed.

If noinst_* is used then automake will generate a static library but
this won't work with LD_PRELOAD so we then need an extra custom rule
to link that into a shared library. The custom rule uses the $(LINK)
Makefile var which gets put in the Makefile because of the static
library. We pass libtool a stub -rpath option which causes it to
generate a shared library.

tests/tools/Makefile.am

@@ -1,14 +1,18 @@
-lib_LTLIBRARIES =
+noinst_LTLIBRARIES =
+
+build_shared_libs =
 
 if HAVE_LIBDL
 
-lib_LTLIBRARIES += libdisable-npots.la
+noinst_LTLIBRARIES += libdisable-npots-static.la
+
+build_shared_libs += libdisable-npots.la
 
 endif
 
-libdisable_npots_la_SOURCES = disable-npots.c
+libdisable_npots_static_la_SOURCES = disable-npots.c
 
-libdisable_npots_la_LIBADD = -ldl
+libdisable_npots_static_la_LIBADD = -ldl
 
 INCLUDES = \
 	-I$(top_srcdir)/clutter	                        \
@@ -16,13 +20,19 @@ INCLUDES = \
 	$(CLUTTER_CFLAGS)                               \
 	-D_GNU_SOURCE
 
-all-local : disable-npots.sh
+all-local : disable-npots.sh $(build_shared_libs)
 
 clean-local :
-	rm -f disable-npots.sh
+	rm -f disable-npots.sh libdisable-npots.la
 
 disable-npots.sh : $(top_builddir)/tests/tools/disable-npots.sh.in
 	sed 's|--builddir--|'`cd '$(top_builddir)' && pwd`'|' < $< > $@ && \
 	chmod 755 disable-npots.sh
 
+# Also put the static library into a shared library. We need to do
+# this without the automake magic because we don't want it to get
+# installed
+libdisable-npots.la : libdisable-npots-static.la
+	$(LINK) -ldl -rpath /nowhere libdisable-npots-static.la
+
 EXTRA_DIST = README disable-npots.sh.in