Re: really confused by mips target formats

["Maciej W. Rozycki" <macro at linux-mips dot org>]

On Tue, 28 Feb 2006, Eric Fisher wrote:

> Let's just talk about elf flavour. What are the traditional mips,
> non-traditional mips and newabi? Why do both traditional mips and
> non-traditional mips contain newabi?

 The existence of the traditional and non-traditional targets results from 
a few subtle differences in how files are generated depending on whether 
they are to be as defined by the generic ELF specification or the SGI 
variation in areas that are not really processor specific.  Most notably 
the definition of what constitutes a local symbol which may affect the 
order of symbols in symbol tables.

 The old ABI (o32) vs new ABIs (n32, n64) difference is independent from 
the above and results from different register sizes, calling conventions, 
etc.

> Why does the object file assembled by mips-linux-as have elf32-tradbigmips
> format? While one by mips-elf-as has elf32-bigmips?

 It depends on the default emulation as configured when it was built.  
Unfortunately it does not seem to be possible to select another BFD target 
for gas.  Possible workarounds include running `ld -r' or `objcopy' on the 
object file, but as most likely completely untested these might not work 
due to bugs either.

  Maciej