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Peter Anvin" , Andy Lutomirski , x86@kernel.org Subject: Re: [PATCH v2] x86: fix early boot crash on gcc-10 Message-ID: <20200417103808.GW20730@hirez.programming.kicks-ass.net> References: <20200328084858.421444-1-slyfox@gentoo.org> <20200413163540.GD3772@zn.tnic> <20200415074842.GA31016@zn.tnic> <20200415231930.19755bc7@sf> <20200417075739.GA7322@zn.tnic> <20200417080726.GS2424@tucnak> <20200417084224.GB7322@zn.tnic> <20200417085859.GU2424@tucnak> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200417085859.GU2424@tucnak> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 17, 2020 at 10:58:59AM +0200, Jakub Jelinek wrote: > Or go with the for (;;);, I don't think any compiler optimizes those away; > GCC 10 for C++ can optimize away infinite loops that have some conditional > exit because the language guarantees forward progress, but the C language > rules are different and for unconditional infinite loops GCC doesn't > optimize them away even if explicitly asked to -ffinite-loops. 'Funnily' there are people building the kernel with C++ :/