On 2021-02-28 13:31, Hans-Peter Nilsson wrote:
On Fri, 26 Feb 2021, Thiago Macieira via Gcc-patches wrote:
On Friday, 26 February 2021 11:31:00 PST Andreas Schwab wrote: On Feb
26 2021, Thiago Macieira wrote: On Friday, 26 February 2021 10:14:42
PST Andreas Schwab wrote: On Feb 26 2021, Thiago Macieira via
Gcc-patches wrote: - alignas(__alignof__(ptrdiff_t)) ptrdiff_t
_M_a;
+ alignas(__alignof__(int)) int _M_a;
Futexes must be aligned to 4 bytes.
Agreed, but doesn't this accomplish that?
No. It uses whatever alignment the type already has, and is an
elaborate no-op.
I thought so too when I read the original line. But I expected it was
written
like that for a reason, especially since the same pattern appears in
other
places.
I can change to "alignas(4)" (which is a GCC extension, I believe). Is
that
the correct solution?
IMNSHO make use of the corresponding atomic type. Then there'd
be no need for separate what's-the-right-align-curse games.
There is no predicate wait on atomic<T>.
brgds, H-P
