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Re: Should -fcross-jumping be part of -O1?
- From: Geoff Keating <geoffk at geoffk dot org>
- To: David Carlton <carlton at kealia dot com>
- Cc: gcc mailing list <gcc at gcc dot gnu dot org>
- Date: 02 Dec 2003 11:48:30 -0800
- Subject: Re: Should -fcross-jumping be part of -O1?
- References: <3FC0DCD0.9000106@coyotegulch.com><20031123162248.GA336@atrey.karlin.mff.cuni.cz><3FC0EC7E.7070800@coyotegulch.com><20031123173321.GO15575@kam.mff.cuni.cz><3FC0F7A6.4010103@coyotegulch.com><20031123181903.GW15575@kam.mff.cuni.cz><3FC11F13.2090708@coyotegulch.com><877k1fmxr4.fsf@egil.codesourcery.com><yf2znebtaxt.fsf@hawaii.kealia.com>
David Carlton <carlton@kealia.com> writes:
> On Tue, 02 Dec 2003 00:26:07 -0800, "Zack Weinberg"
> <zack@codesourcery.com> said:
>
> > -O0 No optimization whatsoever.
> > Except maybe do obviously-dead code elimination.
>
> This is obviously a very special case, but dead code elimination
> sometimes makes it difficult to write tests for GDB's test suite. And
> even when working on real programs I occasionally insert dead code as
> a place where I can set breakpoints. So, personally, I'd prefer that
> -O0 be pretty stupid. (Though I don't mind if it's not the default.)
I thought that the dead code elimination at -O0 is supposed to work
properly with GDB: it puts in a 'nop' that the breakpoint can target.
Is this not working?
--
- Geoffrey Keating <geoffk@geoffk.org>