Reproducable builds

[Hal Murray]

> I think I have them all correct now.  Go ahead and merge any that work
> for you. 

1529 through 1548 all pass my tests.

But there is a glitch with 1530 that I would be happier if I understood.  
Your MR is 2 patches.  The first patch breaks something.  The second patch 
unbreaks it.

The first patch is 6323 lines.  The second is 565.  That makes it much 
simpler to search the second patch to look for the change that fixes it.  
I haven't found anything yet.

I'm going to try bisecting.

-- 
These are my opinions.  I hate spam.