Re: Re: [COMMITTERS] pgsql: Fix blatantly uninitialized variable in recent commit.

On Thu, 2011-02-17 at 10:09 -0500, Tom Lane wrote:
> Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
> > On Thu, 2011-02-17 at 00:53 +0000, Tom Lane wrote:
> >> Doesn't anybody around here pay attention to compiler warnings?
>
> > If you see one, then I accept one was there. I didn't see one, and a
> > full make distclean and re-compile doesn't show a compiler warning for
> > that either. So I guess I'm doing something wrong, on this platform:
>
> > I'm using Ubuntu 10.04 LTS, with commands for development:
> > ./configure --enable-cassert --enable-depend --enable-debug
> > make -j4
>
> Hmm ... the only plausible reason I can think of for gcc not showing
> that warning would be building with -O0 (which disables the flow graph
> computations needed to detect uses of uninitialized values). Your
> configure command doesn't betray any such thing, but maybe you've got
> some CFLAGS overrides you're not showing us?
>
> I usually find that -O1 is the best compromise setting for development
> builds. It enables uninitialized-variable warnings but doesn't produce
> code that's completely unfriendly to gdb. (Sometimes I do recompile a
> specific file at -O0 if it's making no sense during single-stepping.)

Just recompiled with explicit CFLAGS=-O1 using my distro's gcc 4.4.3

The only difference in messages I got was

dbsize.c: In function ‘pg_relation_filepath’:
dbsize.c:570: warning: ‘rnode.dbNode’ may be used uninitialized in this
function
dbsize.c:570: warning: ‘rnode.spcNode’ may be used uninitialized in this
function

--
Simon Riggs http://www.2ndQuadrant.com/books/
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