On Thu, 26 Nov 1998, Todd Whitesel wrote:

: As far as I am concerned, a conditional -O0 in a makefile is the way to go,

No.  This is a warning flow analysis bug, not an optimizer codegen bug.

The appropriate hack is:

.if (${MACHINE_ARCH} == "m68k")
CWARNFLAGS += -Wno-uninitialized
.endif

All other -O0 hacks for similar reasons are just bogus and should use
something like the above.  We should *not* turn off optimization just
because warning flow analysis is borken.  Flow analyis for -Wunused is so
broken in egcs, for example, that I've turned off -current egcs's -Wunused
(as part of -Wall) until that is fixed in the compiler.

: 	grep -w -- -O0 `find /usr/src -type f -name 'Makefile*'`
: 
: ... any time someone wants to go bogon hunting.

Actually, grepping for CWARNFLAGS would be informative, as well.  It's
already in use in a couple parts of the tree for -Wno-format-y2k, a hack I
added to egcs to turn off strftime() warnings about %y.

: (Yes, this might be related to what I've been going through with arm32 lately)

It's likely not.  The Makefile hacks needed for arm32 are real bugs in the
gcc 2.7.2 optimized codegen for arm32.

Fortunately, egcs is much better about it, and will be the default on arm32
"soon enough".

-- 
-- Todd Vierling (Personal tv@pobox.com; Bus. todd_vierling@xn.xerox.com)