Date: Sun, 3 Jan 2016 17:57:28 +0100 From: robbinson defau <robbinsondefau@gmail.com> To: "Kristian A. Hiorth" <kah@kahnews.net> Cc: freebsd-hackers@freebsd.org Subject: Re: variables optimized out Message-ID: <CAA99N-MaHyBO4zH-pN=k7GZvRZWMaMpFijM-2s6hahyRjK8DWQ@mail.gmail.com> In-Reply-To: <568930A0.6010405@kahnews.net> References: <CAA99N-OKyxzVaJ4ayXRUGAoovNtHFXTpOXPkwhdw9k3LEMnOtw@mail.gmail.com> <568930A0.6010405@kahnews.net>
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Hi, That seems to help a lot. Thanks for the info! /DF On Sun, Jan 3, 2016 at 3:30 PM, Kristian A. Hiorth <kah@kahnews.net> wrote: > On 01/03/2016 02:38 PM, robbinson defau wrote: > >> Hi all, >> >> Im debugging some issues in the kernel and as the kernel is compiled by >> default with -O2, a lot of variables are optimized out. So i made changes >> to make.conf (CFLAGS and COPTFLAGS).\ >> >> All builds fine, but I get the weirdest of panics that most certainly not >> happen with -O2. So it's likely i'm doing something wrong. What would be >> the correct way to be able to debug the kernel and have it build such that >> locals and function arguments are not optimized out? >> >> Thanks in advance, >> >> /DF >> > > Hi, > > sounds like stack overflows, did you try increasing kernel stack size? > Stuff like WITNESS causes a lot of stack growth when the optimizer inlines > fewer calls. > > I've run an -O0 kernel with > options KSTACK_PAGES=6 > > without too many problems. > > Hope this helps, > Kristian > > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" >
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