Link binaries with -Wl,--as-needed to reduce library dependencies

Using pkg-config --libs to get library link lines has the disadvantage
of bringing in many more library dependencies than actually necessary,
since that assumes that dependencies of libraries need to be specified
explicitly at link time (even when the library is itself linked against
those dependencies).  Using GNU ld's --as-needed option causes these
unnecessary dependencies to be omitted from the binary.

--as-needed needs to be specified after all the objects to be linked
into the binary and before the libraries, so some reordering of the link
command line is needed.

diff --git a/Makefile b/Makefile
index 15c8199..65bb61e 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 CC = gcc
 CFLAGS = -Wall -Os $(EXTRA_CFLAGS)
 CPPFLAGS = `pkg-config --cflags dbus-glib-1` $(EXTRA_CPPFLAGS)
 CC = gcc
 CFLAGS = -Wall -Os $(EXTRA_CFLAGS)
 CPPFLAGS = `pkg-config --cflags dbus-glib-1` $(EXTRA_CPPFLAGS)

-LDFLAGS = `pkg-config --libs dbus-glib-1` $(EXTRA_LDFLAGS)
+LDFLAGS = -Wl,--as-needed `pkg-config --libs dbus-glib-1` $(EXTRA_LDFLAGS)

 PREFIX = /usr
 
 APP = browser-switchboard
 PREFIX = /usr
 
 APP = browser-switchboard

@@ -19,7 +19,7 @@ fremantle:
 
 
 $(APP): dbus-server-glue.h $(obj)
 
 
 $(APP): dbus-server-glue.h $(obj)

-       $(CC) $(CFLAGS) $(LDFLAGS) -o $(APP) $(obj)
+       $(CC) $(CFLAGS) -o $(APP) $(obj) $(LDFLAGS)

 
 dbus-server-glue.h:
        dbus-binding-tool --mode=glib-server --prefix="osso_browser" \
 
 dbus-server-glue.h:
        dbus-binding-tool --mode=glib-server --prefix="osso_browser" \

diff --git a/config-ui/Makefile b/config-ui/Makefile
index d41444f..8bc3749 100644 (file)
--- a/config-ui/Makefile
+++ b/config-ui/Makefile
@@ -5,7 +5,7 @@ CPPFLAGS = -I../ `pkg-config --cflags gtk+-2.0` $(EXTRA_CPPFLAGS)
 CPPFLAGS_HILDON = -DHILDON `pkg-config --cflags hildon-1`
 CPPFLAGS_PLUGIN = $(CPPFLAGS_HILDON) -DHILDON_CP_APPLET \
        `pkg-config --cflags libosso` `pkg-config --cflags hildon-control-panel`
 CPPFLAGS_HILDON = -DHILDON `pkg-config --cflags hildon-1`
 CPPFLAGS_PLUGIN = $(CPPFLAGS_HILDON) -DHILDON_CP_APPLET \
        `pkg-config --cflags libosso` `pkg-config --cflags hildon-control-panel`

-LDFLAGS = `pkg-config --libs gtk+-2.0` $(EXTRA_LDFLAGS)
+LDFLAGS = -Wl,--as-needed `pkg-config --libs gtk+-2.0` $(EXTRA_LDFLAGS)

 LDFLAGS_HILDON = `pkg-config --libs hildon-1`
 LDFLAGS_PLUGIN = -shared $(LDFLAGS_HILDON) \
        `pkg-config --libs libosso` `pkg-config --libs hildon-control-panel`
 LDFLAGS_HILDON = `pkg-config --libs hildon-1`
 LDFLAGS_PLUGIN = -shared $(LDFLAGS_HILDON) \
        `pkg-config --libs libosso` `pkg-config --libs hildon-control-panel`

@@ -36,21 +36,22 @@ fremantle-plugin:
        @$(MAKE) EXTRA_CPPFLAGS='-DFREMANTLE $(EXTRA_CPPFLAGS)' $(PLUGIN)
 
 $(APP): $(app_obj)
        @$(MAKE) EXTRA_CPPFLAGS='-DFREMANTLE $(EXTRA_CPPFLAGS)' $(PLUGIN)
 
 $(APP): $(app_obj)

-       $(CC) $(CFLAGS) $(LDFLAGS) -o $(APP) $(app_obj)
+       $(CC) $(CFLAGS) -o $(APP) $(app_obj) $(LDFLAGS)

 
 %.app.o: %.c
        $(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ $<
 
 $(HILDON_APP): $(happ_obj)
 
 %.app.o: %.c
        $(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ $<
 
 $(HILDON_APP): $(happ_obj)

-       $(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_HILDON) \
-               -o $(HILDON_APP) $(happ_obj)
+       $(CC) $(CFLAGS) -o $(HILDON_APP) $(happ_obj) \
+               $(LDFLAGS) $(LDFLAGS_HILDON)

 
 %.happ.o: %.c
        $(CC) $(CFLAGS) $(CPPFLAGS) $(CPPFLAGS_HILDON) -c -o $@ $<
 
 $(PLUGIN): $(plugin_obj)
 
 %.happ.o: %.c
        $(CC) $(CFLAGS) $(CPPFLAGS) $(CPPFLAGS_HILDON) -c -o $@ $<
 
 $(PLUGIN): $(plugin_obj)

-       $(CC) $(CFLAGS) $(CFLAGS_PLUGIN) $(LDFLAGS) $(LDFLAGS_PLUGIN) \
-               -o $(PLUGIN) $(plugin_obj)
+       $(CC) $(CFLAGS) $(CFLAGS_PLUGIN) -o $(PLUGIN) $(plugin_obj) \
+               $(LDFLAGS) $(LDFLAGS_PLUGIN)
+               

 
 %.plugin.o: %.c
        $(CC) $(CFLAGS) $(CFLAGS_PLUGIN) $(CPPFLAGS) $(CPPFLAGS_PLUGIN) \
 
 %.plugin.o: %.c
        $(CC) $(CFLAGS) $(CFLAGS_PLUGIN) $(CPPFLAGS) $(CPPFLAGS_PLUGIN) \