Link with libfloat if necessary.

libc/Makefile

@@ -58,7 +58,7 @@ shared: $(TOPDIR)lib/$(LIBNAME)
 	$(LD) $(LDFLAGS) $(VERSION_SCRIPT) -soname=$(SHARED_MAJORNAME) -o $(SHARED_FULLNAME) \
 		--whole-archive $(LIBNAME) \
 		$(TOPDIR)libc/misc/internals/interp.o --no-whole-archive \
-		-init __uClibc_init $(LIBGCC)
+		-init __uClibc_init $(LIBGCC) $(LDADD_LIBFLOAT)
 	@true #$(RM) -r tmp
 	$(INSTALL) -d $(TOPDIR)lib
 	$(RM) $(TOPDIR)lib/$(SHARED_FULLNAME)