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    SubjectRe: Weird __put_user_asm behavior

    > The old code evaluates addr once, your new code evaluates it twice.
    > Have you tried an inline function instead of a macro?
    > linux/fs/binfmt_elf.c contains a few lines that probably break if 'addr'
    > is evaluated twice:
    > <<<<<<<
    > argv = (elf_caddr_t *) sp;
    > if (!ibcs) {
    > __put_user((elf_addr_t)(unsigned long) envp,--sp);
    > __put_user((elf_addr_t)(unsigned long) argv,--sp);
    > }
    > <<<<<<<<<

    Double evaluation of the (addr) expression seems to be my problem, not
    register clobbering as I first thought. Although all the macro's that are
    using __put_user_asm also use
    __typeof__(*(addr)) *__their_local_addr = (addr);
    // further use __their_local_addr ...
    one apparently needs to repeat this 'localization' of (addr) in order to
    have only one evaluation of (addr) at the end.
    I always found the macro paragraph in my first C book -'A Book on C'- a
    little too short :).

    Anyway, thanks to all for the help.


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