Re: [lttng-dev] [PATCH] Add ACCESS_ONCE() to avoid compiler splitting assignments

2013-01-25 Thread Paul E. McKenney
On Sun, Jan 20, 2013 at 03:51:31PM -0500, Mathieu Desnoyers wrote: > * Paul E. McKenney (paul...@linux.vnet.ibm.com) wrote: > > On Wed, Jan 16, 2013 at 07:50:54AM -0500, Mathieu Desnoyers wrote: > > > * Mathieu Desnoyers (mathieu.desnoy...@efficios.com) wrote: > > > > * Paul E. McKenney (paul...@li

Re: [lttng-dev] [PATCH] Add ACCESS_ONCE() to avoid compiler splitting assignments

2013-01-20 Thread Mathieu Desnoyers
* Paul E. McKenney (paul...@linux.vnet.ibm.com) wrote: > On Wed, Jan 16, 2013 at 07:50:54AM -0500, Mathieu Desnoyers wrote: > > * Mathieu Desnoyers (mathieu.desnoy...@efficios.com) wrote: > > > * Paul E. McKenney (paul...@linux.vnet.ibm.com) wrote: > > > > As noted by Konstantin Khlebnikov, gcc can

Re: [lttng-dev] [PATCH] Add ACCESS_ONCE() to avoid compiler splitting assignments

2013-01-19 Thread Paul E. McKenney
On Wed, Jan 16, 2013 at 07:50:54AM -0500, Mathieu Desnoyers wrote: > * Mathieu Desnoyers (mathieu.desnoy...@efficios.com) wrote: > > * Paul E. McKenney (paul...@linux.vnet.ibm.com) wrote: > > > As noted by Konstantin Khlebnikov, gcc can split assignment of > > > constants to long variables (https:/

Re: [lttng-dev] [PATCH] Add ACCESS_ONCE() to avoid compiler splitting assignments

2013-01-16 Thread Mathieu Desnoyers
* Mathieu Desnoyers (mathieu.desnoy...@efficios.com) wrote: > * Paul E. McKenney (paul...@linux.vnet.ibm.com) wrote: > > As noted by Konstantin Khlebnikov, gcc can split assignment of > > constants to long variables (https://lkml.org/lkml/2013/1/15/141), > > though assignment of NULL (0) is OK. As

Re: [lttng-dev] [PATCH] Add ACCESS_ONCE() to avoid compiler splitting assignments

2013-01-15 Thread Mathieu Desnoyers
* Paul E. McKenney (paul...@linux.vnet.ibm.com) wrote: > As noted by Konstantin Khlebnikov, gcc can split assignment of > constants to long variables (https://lkml.org/lkml/2013/1/15/141), > though assignment of NULL (0) is OK. Assuming that a gcc bug is > fixed (http://gcc.gnu.org/bugzilla/attach