Re: Clang buildworld failure due to multiple definitions of __isnanf

On Tue, 28 Jun 2011, Benjamin Kaduk wrote:

> On Mon, 27 Jun 2011, Eric McCorkle wrote:
>
>> make.conf:
>> CPUTYPE?=core2
>> .if !defined(CC) || ${CC} == "cc"
>> CC=clang
>> CFLAGS=-Qunused-arguments
>> .endif
>> .if !defined(CXX) || ${CXX} == "c++"
>> CXX=clang++
>> .endif
>> NO_WERROR=
>> WERROR=
>> NO_FSCHG=
>> PERL_VERSION=5.12.3
>> 
>> Just noticed, the CFLAGS would disable optimization, which would explain 
>> why no one else seems to see this.  Still, I think the underlying issue 
>> warrants investigation.
>
> I seem to recall that our gcc-4.2 with -O0 is known to be buggy -- certainly 
> I just tripped over a panic in a third-party kernel module build using 
> bsd.kmod.mk with -O0 that was fixed by compiling the object in question with 
> -O.
> It is not terribly easy to search for, but my archives find at least 
> http://lists.freebsd.org/pipermail/freebsd-current/2007-August/076028.html
>
> I would try with -O1 and confirm that your issues go away, and not spend time 
> on the core issue if it proves to be a gcc bug.
>
> Unfortunately, we are stuck with an old gcc in base ... though I have yet to 
> see if clang -O0 has issues with my module.

Wow, I juxtaposed the two compilers due to working on too little sleep. 
Please disregard, and sorry for the noise.

-Ben