On 9/5/19 3:00 AM, Kyrill Tkachov wrote:
>> +/* Define the symbol gating the LSE implementations. */
>> +extern _Bool __aa64_have_atomics
>> + __attribute__((visibility("hidden"), nocommon));
>> +
>
> Bootstrapping this patch series on an Armv8-A system with OOL atomics enabled
> by default gave me link errors
>
> when building libgomp about __aa64_have_atomics being undefined.
>
> I haven't followed the series from the start so maybe I'm missing some things,
> but I don't see where this variable is supposed to "live"?
Removing the extern here is the correct fix.
Obviously the v3 patch set conversion from C to assembly wasn't properly
tested, or I made some last-minute changes before posting. Time has erased
that memory.
> Removing the 'extern' from here allows the bootstrap to proceed but it fails
> at
> a later stage with bizzare errors like:
>
> In file included from build/gencondmd.c:51:
> $SRC/gcc/config/aarch64/constraints.md: In function ‘bool
> satisfies_constraint_S(rtx)’:
> $SRC/gcc/config/aarch64/constraints.md:120:10: error: ‘C’ was not declared in
> this scope; did you mean ‘PC’?
> 120 | (define_constraint "Y"
> | ^
> | PC
>
> which looks like a miscompilation of sorts.
I noticed a couple of typos in the assembly that used the wrong register form
(wN vs xN) on the LSE instructions. By chance were you testing on a system
with LSE instructions enabled?
r~
