RFC: Program Properties

[Jose E. Marchesi]

    > 1. Minimum ISAs.  Executables and shared objects, which are optimized
    > specifically to run on a particular processor, will not run on processors
    > which don't support the same set of ISAs.  Since x86 only has EM_IAMCU,
    > EM_386 and EM_X86_64 ELF machine codes, run-time loader needs additional
    > information to tell if an executable or a shared object is compatible
    > with available ISAs.
    
    Why cant the following be defined as processor specific e_flags (like
    other processors do) in elf.h itself?

It is easy to exhaust the space of EF_* flags.  In sparc this happened
many years ago, so we had to start using the tags Tag_GNU_SPARC_HWCAPS
and Tag_GNU_SPARC_HWCAPS2 to denote hardware capabilities.