Re: malloc was optimized out
Re: malloc was optimized out
- Subject: Re: malloc was optimized out
- From: Steve Sisak <email@hidden>
- Date: Mon, 04 Jul 2016 20:12:49 -0400
On Jul 4, 2016, at 7:37 PM, Quincey Morris <email@hidden> wrote:
I think the only way the allocator will know if the requested memory is available to this app is to try writing to it. I dunno what the C language experts think, but this suggests to me that you could try using calloc instead for exactly that reason. It’d be a lot slower for large memory blocks, but if it returns nil on failure to write then that should be what you want to know.
Actually, this is false — see the link I just sent to Dmitry:
a large calloc() is preferred because it simply allocates uninitialized address space which is zeroed by the VM system automatically when accessed.
But (and this answer may answer Dmitry’s question) calloc/malloc only allocates the address space — the actually failure may not occur until you run out of swap space.
I think there may be more information in the guidelines, but don’t have time to re-read the full document at the moment.
Dmitry, you should.
HTH,
-Steve
|
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Xcode-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden