Windows tools produce differant binary files

[Chris Johns]

Mick Davis wrote:
> 
> We're using the msys environment on windows to build for our coldfire 
> target.  I'm finalising the upgrade to 4.6.99-3, which has produced a 
> small improvement in our target's idle time.
> 

Nice.

> I've got a problem using the rtems4.7-m68k-20060707-1.exe tools, which I 
> also reproduced using the same tools, but built myself, under msys.

There is a newer release. Please check the Wiki page. It should be the 
same compiler but it would be nice if you could try it.

> The problem is that the binary I'm producing isn't always the same, 
> depending on the PC I use to build it.  3 older PCs using windows 2000 
> produce one .srec, and 2 newer PCs running windows XP produce another.

Is it the same repeatable difference on each machine ?

> As well as just being suspicious, this is a problem for our quality 
> system, since we support a number of engineers.

It should be the same on each machine.

> I was speculating that 
> the level of optimisation may depend on the capabilities of the build 
> machine?

We have a cross compiler so I would be surprised if this is the problem.

Until I can see the code and difference it would be hard to isolate.

If you wish we can take this off line to resolve.

> 
> I use a -DNDEBUG=1 compilation flag to keep build system file names out 
> of the output.  I've checked this by running the output .elf through the 
> 'strings' program, and I don't see any file names.
>

This could still be a problem but you mention a different register used 
which rules this out.

> I've been through the gcc manual, and none of the environment variables 
> it mentions exist.  I've been adjusting the variables which are 
> different between PCs, but none have an effect.

I do not understand what you mean here.

> Looking at the differences in the binaries themselves, the differences 
> appear to be in the code, but harmless. For example, the register d0 is 
> used instead of d1.  Either binary appears to run without a problem.

This is interesting. I would not expect to see this if everything is the 
same.

> 
> Can anyone point me to something in the build process which might 
> produce these differences? Do the automake files put build information 
> into the executable somewhere?

Could you please run the build with -save-temps on each machine and diff 
the files ? If they are same then we have the same environment set up. 
We can then look at the compiler for what is happening.

Regards
Chris