[phobos] FreeBSD 32 still fails unittests for std.datetime

[Walter Bright]

On 5/2/2011 11:06 PM, Jonathan M Davis wrote:
>
> I'm afraid that I don't understand what the problem is then. Can the linker
> not handle a 4.6 Mb object file? Granted, that's not a small file, but I
> wouldn't have thought that that would do in the linker.

It is an unusually large .o file, though. Maybe ld has some exponential behavior 
with the size of a .o file.

> And, of course, that raises the question as to why the object file is so large
> when compiling with unit tests.

(I made a mistake, it's 5Mb compiled with -unittest.) By replacing a few 
_assertPred's with assert, compiling and looking at the .o file size, each one 
consumes an extra 400 to over 1000 bytes. There are 4000 _assertPred's there, so 
that explains where the size comes from. There are 5 args that get pushed on the 
stack for each call to _assertPred, and one of those is a delegate (the lazy 
parameter).

I appreciate that using _assertPred saves you time and effort in development, 
but once it is developed it is a bit expensive to carry it around. I wonder if 
there's an easy way to swap it out with assert.

Sigh. Even obj2asm crashes with this .o file, but that's my fault.

Running "strings" on the .o for a non-unittest compile shows a lot of redundant 
strings that can be factored out to save space, such as "Standard Time" 
appearing 80 times or so.


>   Part of it likely comes from the fact that the
> unit tests actually use the stuff in std.datetime, so all of the templated
> types and functions get instantiated, and they wouldn't when just compiling
> Phobos, unless something else in Phobos is using them. And maybe there's
> something in the unit tests which instantiates a bunch of extra templates. I
> don't know. Or did you compile with -release and -O _and_ -unittest? That
> would change things considerably, since that would imply a difference betwen
> release and non-release instead of a difference with regards to whether unit
> tests are compiled in.
>
> Regardless, I don't know why the linker wouldn't like a 4.6 Mb object file.
> And while fixing dmd's memory consumption won't fix the problem, it might make
> it so that dmd actually finishes compiling and moves on to the linker rather
> than forcing you to delete unit tests. And whatever the problem may be,
> clearly it has something to do with the differences between your machine and
> the auto tester, since the auto tester is fine. So, regardless of dmd,
> whatever the linker's problem is, there's something about your machine that
> makes it fail while it succeeds on the auto tester.

My FreeBSD box is a 10 year old machine, with not much memory on it.

> And if all you want to do is to not have std.datetime fail on your machine,
> you can remove or comment out the line
>
>      version = testStdDateTime;
>
> (line #145, I believe) on your machine, and none of the std.datetime unit
> tests will be compiled in. It's already not defined on Windows specifically
> because dmd definitely runs out of memory compiling std.datetime on Windows
> when compiling all of Phobos' unit tests:
> http://d.puremagic.com/issues/show_bug.cgi?id=5454 (it does fine, if you
> compile std.datetime separately though).
>

For now, I'll disable the unittests for FreeBSD.