VMS Help CC, Messages, NOREGAVAIL  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Message        Unable to satisfy program register allocation
                requirements.

 Description    The compiler is unable to allocate all the registers
                requested by the program.  This most often happens
                when asm directives require too many registers.

 User Action    Rework the asm directives so they use fewer registers