-PKGS_CFLAGS := $(foreach p,$(PKGS),$(shell pkg-config --cflags $p))
-PKGS_LIBS := $(foreach p,$(PKGS),$(shell pkg-config --libs $p))
+EXTPREFIX = $(abs_builddir)/$(OUTDIR)/inst
+
+join-paths = $(if $(filter /%,$2),$2,$1/$2)
+ext-srcdir = $(or $($1_SRCDIR),../$1)
+
+PKG_CONFIG = PKG_CONFIG_LIBDIR=$(OUTDIR)/inst/lib/pkgconfig \
+ pkg-config --static
+
+PKGS_CFLAGS := $(foreach p,$(PKGS),$(shell $(PKG_CONFIG) --cflags $p))
+PKGS_LIBS := $(foreach p,$(PKGS),$(shell $(PKG_CONFIG) --libs $p))