ios5 - Copied blocks and CLANG leak warnings -

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i have method takes block:

- (void)methodwithblock:(blocktype)block

the method starts out copying block, because asynchronous things before using it, , discarded otherwise. calls method within block, , releases it, within block. summarily:

- (void)methodwithblock:(blocktype)block {     block = [block copy];     [something asyncstuffwithfinishedblock:^{         // ..         block();         [block release];     }]; }

clang complains memory leaks "block". if remove copy , release statements block gone time it's called -- @ least earlier crashes indicates case.

is wrong way things? if so, how should above -- i.e. block callback within block statement in method? can't store block instance variable, method called repeatedly different arguments while asynchronous part happening.

first, -copy , -release should unnecessary. -asyncstuffwithfinishedblock: method must copy block that's passed it. when block copied , references other block objects, copies block objects, too. need figure out real nature of crash seeing.

second, releasing wrong thing. [block copy] not modify block (the receiver of -copy message) somehow turning copy. returns copy of block. returned copy want reference both in invocation statement (block();) , when releasing.

so, do:

block = [block copy]; [something asyncstuffwithfinishedblock:^{     // ..     block();     [block release]; }];

note reassignment of local block variable point copy.

think of way: ever copy string way attempted copy block? do:

[somestring copy]; // ... use somestring ... [somestring release];

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