Block pointer variable 'block' is uninitialized when captured by block
grand-central-dispatch, ios, objective-c
Solution
To just declare your block you would use
void (^block)(void);
then initialize it with
block =^ // Get warning here!
{
next = dispatch_time(next, DELAY_IN_MS * 1000000L);
// Do my periodic thing ...
dispatch_after(next, dispatch_get_main_queue(), block);
}
That is why putting in the semicolon works.
Why it gives you an error without the semicolon: you are referencing block in its own declaration/assignment. You are using it in the "dispatch_after" call, but its not fully set up yet.
Problem
I'm using the code seen here to execute code periodically: ``` #define DELAY_IN_MS 1000 __block dispatch_time_t next = dispatch_time(DISPATCH_TIME_NOW, 0); void (^block)(void) = ^ // Get warning here! { next = dispatch_time(next, DELAY_IN_MS * 1000000L); // Do my periodic thing ... dispatch_after(next, dispatch_get_main_queue(), block); } ``` This results in a warning (see title). I have two questions about this warning: - What does it mean? - Why does the warning go away when I write: `void (^block)(void); block = ^`?