[fpc-pascal] Inclocked/declocked

[Mark Morgan Lloyd]

On 11/09/17 19:45, Sven Barth via fpc-pascal wrote:

> I've rechecked and the thing is as follows:- the IncLocked call happens each time you assign a dynamic array toanother dynamic array variable or a by-value parameter (this alsoincludes being part of a record, but not a class instance or TP-styleobject)- the DecLocked call happens each time the array is cleared (as long asthe reference count is > 0 this only means a decrement of the count)which happens if you assign Nil, assign a different array (thedestination array is "cleared") or if the array variable goes out of scope
> The two routines are also used in context of Ansi- and UnicodeStringvariables as well as reference counted interfaces (aka COM-styleinterfaces).
> In contrast to what I wrote earlier the compiler does however not ensurea unique array if you only change an element, so given the followingexample:

In the general case, will these force a membar or a cache flush?

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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