[Users] Error on Ubuntu Machine

Hello all,

Could anybody please help me in resolving this error during ./simfactory/bin/sim build --mdbkey make 'make -j2' --thornlist=manifest/ einsteintoolkit.th ?

configure: error: strdup has no C prototype. Try adding -D_XOPEN_SOURCE -D_XOPEN_SOURCE_EXTENDED to CPPFLAGS

I'm doing it on an ubuntu machine but, I got same error when I was doing it on a local cluster.

I tried adding this to CPPFLAGS in vi lib/make/make.config.defn.in but, didn't help.

Thanks in advance. -Rahul