Hi Peff,
On Thu, 8 Oct 2020, Jeff King wrote:
> On Thu, Oct 08, 2020 at 12:06:47PM +0200, Johannes Schindelin wrote:
>
> > My little script also finds this:
> >
> > -- snip --
> > @@ -1231,8 +1231,8 @@ space := $(empty) $(empty)
> >
> > ifdef SANITIZE
> > SANITIZERS := $(foreach flag,$(subst $(comma),$(space),$(SANITIZE)),$(flag))
> > -BASIC_CFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=$(SANITIZE)
> > BASIC_CFLAGS += -fno-omit-frame-pointer
> > +BASIC_CFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=$(SANITIZE)
> > ifneq ($(filter undefined,$(SANITIZERS)),)
> > BASIC_CFLAGS += -DSHA1DC_FORCE_ALIGNED_ACCESS
> > endif
> > -- snap --
> >
> > I am not _so_ sure that we want to order `BASIC_CFLAGS`, but then, it does
> > not hurt, does it?
>
> I agree it would not be wrong to reorder here from the compiler's
> perspective, but:
>
> - the current ordering is not arbitrary; the intent was to show that
> we are enabling -fsanitize, and then follow it up with any other
> related options (first any that apply to all sanitizers, of which
> there is only one, and then any sanitizer-specific ones). The patch
> above splits that logic apart.
>
> - I'd worry that there are cases in which order _does_ matter to the
> compiler. I'm not sure if anything that goes in CFLAGS might
> qualify, but certainly order can matter for other parts of the
> command-line (e.g., static library order).
>
> So it might be setting us up for confusion later.
Fair enough. It's easy to exclude `.*_CFLAGS` via a negative look-behind:
$key = '';
@to_sort = ();
while (<>) {
if ($#to_sort >= 0) {
if (/^$key \+=/) {
push @to_sort, $_;
next;
}
print join('', sort @to_sort);
@to_sort = ();
}
if (/^(\S+(?<!_CFLAGS)) \+=/) {
$key = $1;
push @to_sort, $_;
} else {
print $_;
}
}
if ($#to_sort >= 0) {
print join('', sort @to_sort);
}
Ciao,
Dscho
