Jaromir Dolecek wrote:
> 
> While compiling i386 kernel from about week ago ...
> 
> cc1: warnings being treated as errors
> ../../../../kern/subr_prf.c: In function `panic':
> ../../../../kern/subr_prf.c:126: warning: unknown conversion type character `:' in format
> ../../../../kern/subr_prf.c:126: warning: too many arguments for format
> 
> line 126 was:
>        printf("panic: %:\n", fmt, ap);

  By any chance, did you install gcc yourself?  If you are
unsure which cc the compile is using (/usr/bin/cc vs.
/usr/local/bin/cc, for example), try:

rm subr_prf.o && make CFLAGS=-v subr_prf.o

That should spit out all sorts of semi-useful stuff, including
the full path of the compiler, assembler, etc.  If it includes a
line of /usr/local/bin/cc, then <bingo> I know the problem --
read on.  If not, just delete this message!

  The problem is that if you have installed gcc yourself, into
/usr/local/bin (say, because you wanted gcc-2.7.2.2 instead of
just 2.7.2), and if /usr/local/bin/cc ends up being on your
path before /usr/bin/cc, then kernel compiles will use
/usr/local/bin/cc, which knows nothing about %: and friends.

  In February I sent a message to the then-new mailing
list tech-toolchain, describing this problem, in addition to
another "/usr/local/bin/gcc versus /usr/bin/gcc" problem.  In
short, I also thought occurrences of %: and %b were supposed to
be obsolete, and mentioned that still using them breaks kernel
builds using, for example, gcc-2.7.2.2 instead of /usr/bin/gcc.

  No one responded with any indication that still having %: and
%b was a bug, so I didn't send in a PR.  Is this the case?  Maybe
tech-toolchain just had too small of an audience at first to get
the attention of Someone Who Knows(tm)...

  The easy work-around is to use 'make CC=/usr/bin/cc' when
building kernels, or add 

makeoptions	CC=/usr/bin/cc

to your kernel config file, until this issue is resolved.

  Hope this helps!

  Brian
-- 
Brian Grayson (bgrayson@ece.utexas.edu)
Graduate Student, Electrical and Computer Engineering
The University of Texas at Austin
Office:  ENS 406       (512) 471-8011
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