make -j fails on high core count machine

[rui314]

It looks like there's a missing dependency in Makefile.in which results in running ranlib on a library while the linker reads that archive file. As a result, the linker occasionally crashes. If I add sleep 1 before running ranlib like below, it fixes the issue (though it's not a correct way to fix it).

diff --git a/Makefile.in b/Makefile.in
index 96089c8..5957a01 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -238,6 +238,7 @@ RDFGEN_TARGET       = \
 sdk:           sdkstatic $(SDK_DYNAMIC) $(HOSTSDK_DYNAMIC)

 sdkstatic:     $(SDK_STATIC) $(HOSTSDK_STATIC)
+               sleep 1
                $(RANLIB) $(SDK_STATIC)
                $(RANLIB) $(HOSTSDK_STATIC)