On 11 November 2011 23:32, Richard Henderson <r...@redhat.com> wrote:
> Cc: Richard Earnshaw <richard.earns...@arm.com>
> Cc: Ramana Radhakrishnan <ramana.radhakrish...@arm.com>
> ---
> gcc/config/arm/arm.c | 4 ++++
> 1 files changed, 4 insertions(+), 0 deletions(-)
>
> diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
> index 6ef6f62..abf8ce1 100644
> --- a/gcc/config/arm/arm.c
> +++ b/gcc/config/arm/arm.c
> @@ -1096,6 +1096,10 @@ arm_set_fixed_conv_libfunc (convert_optab optable,
> enum machine_mode to,
> static void
> arm_init_libfuncs (void)
> {
> + /* For Linux, we have access to kernel support for atomic operations. */
> + if (arm_abi == ARM_ABI_AAPCS_LINUX)
> + init_sync_libfuncs (8);
There is unfortunately no guarantee that your kernel has support for the 64bit
cases, since this was only recently added - and the libgcc code checks
and aborts if linked in.
(As far as I can tell there is approximately one potential user of 64bit atomics
on ARM, so it's important not to do that check for all binaries).
Dave
