RE: toolchain's output depends on toolchain used to build the compiler?

[Omer Zak]

Further questions and things to eliminate:
1. Are there timestamps in the machine code files (presumably embedded
by the linker, because the compile-time ones don't exist, by checking
for identical post-preprocessor files)?
2. The difference in paths suggested by Rony could also be due to
different handling of uppercase/lowercase in Windows vs. Linux.
3. Considering the two groups of client libraries which are identical in
both platforms vs. those which are different - is there any other
difference among them?
                                         --- Omer

On Tue, 2010-02-09 at 10:41 +0200, ronys wrote:
> Hi Shachar,
>  
> Interesting problem. Here are some thoughts:
>  
> Can you control the level of optimization used by the customer? Does
> -O0 create identical object code?
>  
> What are the differences in code? Perhaps they're related to the
> different paths? (If the lengths of the paths are different, and
> they're stored somewhere in the object code, that'll change the
> results)
>  
> You might also want to compare the assembly-language output (-S) to
> narrow down the problem.
>  
> If the customer needs cygwin for internal use, I'd suggest using a
> virtualization solution such as VirtualBox instead - the integration
> with Windows is quite impressive.
>  
> Cheers,
>  
>   Rony
> 
> 
> ______________________________________________________________________
> From: linux-il-boun...@cs.huji.ac.il
> [mailto:linux-il-boun...@cs.huji.ac.il] On Behalf Of Shachar Shemesh
> Sent: Tuesday, February 09, 2010 8:37 AM
> To: linux-il
> Subject: toolchain's output depends on toolchain used to build the
> compiler?
> 
> 
> 
> Hi all,
> 
> I'm having a weird problem at a client's. They need a toolchain for
> both Windows (cygwin) and Linux. What's more, then need the two
> toolchains to match exactly - given identical source code, the
> toolchains must produce the exact same machine code (tested by doing
> objdump -d and diffing the outputs). The toolchains are for bare metal
> power-pc (powerpc-eabi target).
>  [...] 
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