assume, assert, enforce, @safe

[John Colvin via Digitalmars-d]

On Thursday, 31 July 2014 at 15:26:27 UTC, Artur Skawina via 
Digitalmars-d wrote:
> On 07/31/14 15:44, Daniel Gibson via Digitalmars-d wrote:
>> And don't forget this (rather old) case: 
>> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=8537
>> (I really don't get why anyone would want such an 
>> optimization: I want an optimizer to use clever inlining, use 
>> SSE etc where it makes sense and stuff like that - but not to 
>> remove code I wrote.)
>
> That is actually not a bug, but a perfectly valid optimization. 
> The
> compiler isn't clairvoyant and can not know that some data that 
> you
> wrote, but never read back, matters.
>
> The solution is to tell the compiler that you really need that 
> newly
> (over-)written data. Eg
>
>    asm {"" : : "m" 
> (*cast(typeof(password[0])[9999999]*)password.ptr); }
>
> (yes, stdizing compiler barriers would be a good idea)
>
> artur

Any idea how dead store removal interacts with the modern C(++) 
memory model? Another thread could hold a reference to the memory 
being written to.