RE: [avr-gcc-list] avr-libc-1.7.0 fails to compile

[Weddington, Eric]

> -----Original Message-----
> From: 
> address@hidden 
> [mailto:address@hidden
> org] On Behalf Of Joerg Wunsch
> Sent: Wednesday, November 03, 2010 8:25 AM
> To: Georg Lay
> Cc: address@hidden
> Subject: Re: [avr-gcc-list] avr-libc-1.7.0 fails to compile
> 
> As Georg Lay wrote:
> 
> > Thanks, that works. Now using 3.81 instead of 3.80.
> 
> Yes, Dmitry introduced some pattern derivations that require 3.81.
> 
> > One more question: How does avr-libs determine if a 
> specific target is
> > supported or not?
> 
> See configure.ac: it tries to test-compile a minimal piece of code,
> and relies on GCC's exit code to see whether the respective -mmcu
> option value is acceptable or not.  GCC currently has a bug in that it
> doesn't correctly report an error status if the -mmcu option value is
> not actually supported (GCC bug #45261); instead, it relies on the
> assembler to fail.  So if your binutils support a device the compiler
> doesn't support, the decision will be wrong.
> 

And just to be clear, we will fix that bug so that GCC will properly error out.