I have been working with my sysAdmin to get R-devel up and running with 64-bit compilation on our PowerPC cluster. We've got the base install to compile with the following flags: LDFLAGS=-m64 FFLAGS="-m64 -mpowerpc64" FCFLAGS="-m64 -mpowerpc64" CFLAGS="-m64 -mpowerpc64" ../configure --prefix='/N/hd03/mkimpel/BigRed/R_HOME/R-devel/R-build' --x-libraries=/usr/X11R6/lib64 About 50% of my package installs are failing with a message similar to that below: SpikeofOneArray.o' is incompatible with powerpc:common64 output make: *** [CALIB.so] Error 1 My sysAdmin suggested removing the -mpowerpc64 bit flag if I encountered problems, but I though I would run this past our wizards to see if anyone had experience with this problem before recompiling. Mark -- Mark W. Kimpel MD ** Neuroinformatics ** Dept. of Psychiatry Indiana University School of Medicine 15032 Hunter Court, Westfield, IN 46074 (317) 490-5129 Work, & Mobile & VoiceMail (317) 204-4202 Home (no voice mail please) mwkimpel<at>gmail<dot>com