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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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