I really know nothing about Opensolaris 64 bit model and appropriate compiler flags. I would rather have an operating system that gave me just one sane build model by default, with not so much to tweak.
However, this seems to be relevant: http://forums.sun.com/thread.jspa?threadID=5071225 The appropriate flags would be "-xarch=amd64 -KPIC" and all libraries should be built with the same flags. If you inspect the library for the object files that have those offending relocations it may well be that some components (gc, gmp, some files in ECL or in Maxima) are not compiled with the same flags.
BTW, what is the status of Opensolaris support in Sage. This project (Opensolaris) apparently has been totally discontinued by their creators.
Instituto de Física Fundamental, CSIC
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