Inconsistent warning/error message by GCC while linking 32/64 bit binary/library

[Jonathan Wakely]

On 14 December 2015 at 10:15, vijay nag wrote:
> Hello GCC,
>
> I was working on a 32-64 bit porting project and while debugging a
> crash I was very surprised to learn that GCC allowed linking of 64 bit
> library against 32 bit binary with a warning.
>
> If the classic "-L" compiler switch is used, GCC barfs out a "Skipping
> incompatible xxxx.a" error and doesn't emit any executable. However,
> It is interesting to note that if full path of the library is given
> instead as part of compiler flag instead of "-L... -l" incantation,
> GCC emitted the final executable with a warning.  So the question is,
> does ELF specification allow interlinking of 32/64 bit obj files ? Why
> are the compiler messages different in these two cases ? Why did the
> compiler emit the executable in the first place instead of bailing out
> ?

Those aren't compiler messages, they're linker messages, and the
linker is not part of GCC.