[Gc] Alpha issue running test_stack

[Michael Cree]

On 22/10/2012, at 8:08 PM, Ivan Maidanski wrote:
> I guess you haven't got time to inspect assembly of broken code  
> (Alpha target).

I was busy at the time but then I totally forgot about this!

> I think it would be ok for now, just to find which use of  
> AO_EXPECT_FALSE results in broken code and create a workaround  
> avoiding AO_EXPECT_FALSE exactly at that place.

Interestingly doing any one of options 2 or 3 result in the test suite  
passing.

> 2. AO_stack_pop_explicit_aux_acquire:
>   if (AO_EXPECT_FALSE(first != AO_load(list))) {
> ->
>   if (first != AO_load(list)) {
>
> 3. AO_stack_pop_explicit_aux_acquire:
>   if (AO_EXPECT_FALSE(!AO_compare_and_swap_release(list, first,  
> next))) {
> ->
>   if (!AO_compare_and_swap_release(list, first, next)) {

They are quite close together in the code.  I wonder if there is some  
interaction between them.  I really must look at the generated  
assembly to see if the compiler is at fault but that will probably  
have to wait another day or two.

Cheers
Michael.