RE: recent testsuite additions

["Maciej W. Rozycki" <macro at codesourcery dot com>]

On Sat, 23 Aug 2014, Matthew Fortune wrote:

> I'm working through the test failures that I introduced with the FPXX
> ABI patch and am slightly confused about which MIPS targets are supposed
> to use 'traditional' ELF or not. A number of failures are due to the fact
> that I only fixed up the traditional ELF expected output files but a target
> like mipsisa32-elf is not marked as using traditional ELF in mips.exp.

 Thanks for tracking this down.

> I thought the difference between traditional and non-traditional was between
> linux and irix but I'm not sure I have understood the distinction correctly.

 For historical reasons plain mips*-elf (or, speaking canonically, 
mips*-unknown-elf) targets use the IRIX format.  That's the reason why 
mips*-sde-elf targets have been added that use the SVR4 (traditional) 
format.

 And the historical reason is that the SVR4 format was only added sometime 
later on in the game, whereas the IRIX format has always been supported by 
our MIPS target.  The addition happened around ~2000, I still remember 
playing with that as I worked on porting glibc 2.2 to the MIPS target and 
binutils still only supported the IRIX format.  That format turned out 
incompatible with some features required by glibc, specifically 
Solaris-style linker version scripts, I believe, that rely on the SVR4 way 
of symbol sorting, and to address this issue SVR4 format was added to MIPS 
BFD (this is also I think the primary reason why glibc 2.1 never happened 
for MIPS).

  Maciej