Hi, My compilation of lustre failed on error: /usr/src/redhat/BUILD/lustre-1.8.6/lustre/include/lustre/lustre_user.h(190): error #1292: attribute "__may_alias__" ignored } __attribute__((packed, __may_alias__)); My gcc version is: bash-3.2# rpm -qa |grep gcc gcc-4.1.2-46.el5 libgcc-4.1.2-46.el5 bash-3.2# I did not encounter this problem until I turned on mpitest in configuration. Since the attibute still in upstream code, I assume it was my problem. I recalled I simply removed that attribute when I built 1.8.5, but I like to hear what is the right way to solve this compilation error. Thanks, Jay