On Thu, Aug 27, 2020 at 11:24 PM Florian Weimer <fweimer@xxxxxxxxxx> wrote: > > * H. J. Lu: > > > Can you think of ANY issues of passing more arguments to arch_prctl? > > On x32, the glibc arch_prctl system call wrapper only passes two > arguments to the kernel, and applications have no way of detecting that. > musl only passes two arguments on all architectures. It happens to work > anyway with default compiler flags, but that's an accident. In the current glibc, there is no arch_prctl wrapper for i386. There are arch_prctl wrappers with 2 arguments for x86-64 and x32. But this isn't an issue for glibc since glibc is both the provider and the user of the new arch_prctl extension. Besides, long syscall(long number, ...); is always available. -- H.J.
