Re: /usr/bin/as: out of memory allocating 4194304 bytes after a total of 524288000 bytes

On 2012-04-20 15:55, Michael Pounov wrote:
> On Fri, 20 Apr 2012 05:57:18 -0700
> David Wolfskill<david_at_catwhisker.org>  wrote:
...
>> The update after 234416 was to 234454; the attempted buildworld failed:
...
>> /usr/bin/as: out of memory allocating 4194304 bytes after a total of 524288000 bytes
> yep, I sent PR for this issue;)
>
> http://www.freebsd.org/cgi/query-pr.cgi?pr=167064

The root cause of this is the new jemalloc import in r234370.  In
contrib/jemalloc/src/chunk.c, this defines a global variable called
'chunksize'.  At run-time, this turns out to have a value of 4194304, at
least on my i386 system.

However, GNU as *also* has a global variable called 'chunksize', with a
very different intent: it is the default chunk size for its so-called
"obstacks", an internal implementation detail.  It is set to zero in
contrib/binutils/gas/as.c, but normally ends up as 4096 during further
initialization.

Now, because the variable from jemalloc ends up in libc.a, and
/usr/bin/as is statically linked, the jemalloc variable overrides the
one from GNU as.  This causes as to allocate 4 MiB chunks instead of 4
KiB chunks for all its internal processing, and you can guess what
happens with a reasonably large input file. :)

I think the best solution would be for jemalloc to avoid using obvious
names like "chunksize" for its globals, because it is basically a
library that could be linked to any sort of program out there.

For example, it could prefix all its internal-use only globals with
"jemalloc_" or some other mangling scheme.  Jason, any thoughts?