Re: additional GCC warning flags

On Tue, 2004-10-19 at 11:59, Neil Conway wrote:
> -Wpointer-arith might be worth enabling. I'll add it to the GCC CFLAGS
> in the next patch I send in.

Attached is a revised patch. Changes:

- add -Wpointer-arith to the default CFLAGS when using GCC

- add an AC macro AC_PROG_CC_CFLAGS_OPT that checks if $CC supports the
specified command-line option and adds it to the CFLAGS if it does

- replace the hard-coded test for -fno-strict-aliasing with
AC_PROG_CC_CFLAGS, and use AC_PROG_CC_CFLAGS to check for
-Wendif-labels, -Wdeclaration-after-statement, and
-Wold-style-definition

Barring any objections, I will apply this to CVS tomorrow.

BTW, since we're on the topic of compiler options, is there a reason we
don't use -g3 with GCC when --enable-debug is specified? It seems worth
using to me.

-Neil