On Thu, 22 Jun 2023, "Paul E. McKenney" <paul...@kernel.org> wrote:
> On Thu, Jun 22, 2023 at 11:55:55AM -0400, Mathieu Desnoyers wrote:
>> On 6/21/23 19:19, Paul E. McKenney wrote:
> I suggest C11 volatile atomic load/store. Load/store fusing is permitted
> for non-volatile atomic loads and stores, and such fusing can ruin your
> code's entire day. ;-)
After some testing, I got a wall of warnings:
-Wignored-qualifiers:
Warn if the return type of a function has a type qualifier such as
"const". For ISO C such a type qualifier has no effect, since the
value returned by a function is not an lvalue. For C++, the warning
is only emitted for scalar types or "void". ISO C prohibits
qualified "void" return types on function definitions, so such
return types always receive a warning even without this option.
Since we are using atomic builtins, for example load:
type __atomic_load_n (type *ptr, int memorder)
If we put the qualifier volatile to TYPE, we end up with the same
qualifier on the return value, triggering a warning for each atomic
operation.
This seems to be only a problem when compiling in C++ [0] while in C it
seems the compiler is more relaxed on this [1].
Ideas to make the toolchains happy? :-)
[0] https://godbolt.org/z/3nW14M3v1
[1] https://godbolt.org/z/TcTeMeKbW
--
Olivier Dion
EfficiOS Inc.
https://www.efficios.com
_______________________________________________
lttng-dev mailing list
lttng-dev@lists.lttng.org
https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
