bug#8884: closed (Re: bug#8884: wide-int crash)

[Paul Eggert]

On 10/18/11 14:41, Peter Dyballa wrote:

> With Mac OS X 10.5.8 and a PowerPC 7447A CPU GNU Emacs 24.0.90
> launched with -Q can open (tar) files up to 2,047 MB. Ls reports
> that 2,147,450,880 is OK and 2,148,024,320 is too much (2,048
> MB). 2**31 is 2,147,483,648.

Yes, that sounds about right.  There's a ~2**31 byte buffer size
limit due to PTRDIFF_MAX, and Emacs itself enforces this limit.

>       emacs(84226) malloc: *** mmap(size=2113650688) failed (error code=12)
>       *** error: can't allocate region
>       *** set a breakpoint in malloc_error_break to debug

I'm not familiar with this error format, but I expect it's some
Mac OS X thing.  Possibly Mac OS malloc stops working around 2 GiB.
Or perhaps your applications have a system-imposed limit
(try the shell command "ulimit -a").

> I would have thought GNU Emacs could clear all for the file
> allocated memory... There were still 8 or 9 GB disk space available
> for swap/vm to grow,

A single 32-bit process can't possibly allocate more than 4 GiB of
address space, so as long as there's plenty of swap space (which
there appears to be), it's an address-space limit you're running
into, not a swap-space limit.