(j3.2006) co-array variable

Aleksandar Donev donev1
Thu May 31 19:52:53 EDT 2007

On Thursday 31 May 2007 10:42, Bill Long wrote:
> The underlying assumption for volatile is that the memory system operations
> are sufficiently serialized that the load from memory will always get
> either the old value or the new value, and not some bits from one and the
> remaining bits from the other, at least on the granularity of a numeric
> storage unit.
There is no such assumption in VOLATILE...more like an expectation "we hope it 
works for you" and hand-waving. Probablt the expectation is on the user in 
that any changes to the VOLATILE variable value should not occur while it is 
being loaded from memory (say a double loaded as two separate loads). If it 
is a quad real than some systems may have no way of actually enforcing this. 
Certainly not if it is a multi-character string.

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