On Wed, 30 Oct 2019 at 13:18, Yann Ylavic <ylavic....@gmail.com> wrote: > > On Wed, Oct 30, 2019 at 4:37 AM William A Rowe Jr <wr...@rowe-clan.net> wrote: > > > > On Wed, Oct 16, 2019 at 5:11 AM <i...@apache.org> wrote: > >> > >> Author: ivan > >> Date: Wed Oct 16 10:10:59 2019 > >> New Revision: 1868502 > >> > >> URL: http://svn.apache.org/viewvc?rev=1868502&view=rev > >> Log: > >> * atomic/win32/apr_atomic64.c > >> (apr_atomic_read64): Use direct memory read when compiled for x86_x64, > >> since > >> 64-bit reads are atomic in 64-bit Windows [1]. > >> > >> + /* > >> https://docs.microsoft.com/en-us/windows/win32/sync/interlocked-variable-access > >> + * "Simple reads and writes to properly aligned 64-bit variables are > >> atomic > >> + * on 64-bit Windows."*/ > >> + return *mem; > > > > Where are we[1] ensuring *mem is aligned on an 8 byte boundary? > > Since mem is apr_uint64_t, unless the caller is playing nasty casts we > should be good, I think. +1.
Also InterlockedCompareExchange64() as all other interlocked function requires aligned data [1]. So APR already assumes that data is properly aligned. [1] https://docs.microsoft.com/en-us/windows/win32/api/winnt/nf-winnt-interlockedcompareexchange64 -- Ivan Zhakov
