Re: [Request for Help] Reducing gcc 4.9 compilation warnings
On Sun, Apr 19, 2015 at 2:10 AM, Eitan Adler wrote: > > Perhaps it would be useful to do a second run of this, but with a > modified share/mk to silence the most useless of these warnings? > > Sure, that's fine. Can you provide a modified share/mk which you think does the right thing? We can try it. -- Craig ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: [Request for Help] Reducing gcc 4.9 compilation warnings
On Sun, 19 Apr 2015, Adrian Chadd wrote: > I just got a booting mips32 kernel using gcc-4.9.2, and boy are there > a lot of warnings. I'm going to start fixing the ones I find - cleaner > code is better code. Mostly. > > (I'd be happy with -Wall -Werror.) I thought that -Wall was a fixed set of warnings nowhere close to all of them (to avoid breaking peoples' builds as new warnings are introduced), and a larger set would be better. (Things like -Wmaybe-uninitialized have too many false positives to be a desirable -Werror target, though.) -Ben ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: [Request for Help] Reducing gcc 4.9 compilation warnings
On 19 April 2015 at 02:10, Eitan Adler wrote: > " > > On 18 April 2015 at 11:12, Craig Rodrigues wrote: >> Hi, >> >> After the latest commits by members of freebsd-toolchain@ , >> I have managed to compile latest CURRENT world and GENERIC >> kernel on amd64 with an gcc 4.9 external toolchain by doing: >> >>pkg install devel/amd64-xtoolchain-gcc >>cd /usr/src >>sed -i "" -e 's/boot2//' sys/boot/i386/Makefile >>make buildworld CROSS_TOOLCHAIN=amd64-gcc NO_WERROR=yes WERROR= >>make buildkernel CROSS_TOOLCHAIN=amd64-gcc NO_WERROR=yes WERROR= >> >> >> It was necessary to skip boot2 from building because of errors >> reported here: >> https://lists.freebsd.org/pipermail/freebsd-toolchain/2015-April/001658.html >> >> The boot2 compilation errors still need to be worked on. >> >> However, most other things compile with warnings. If folks are >> interested in looking at the warnings, you can see them here: >> >> https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc4.9/warnings17 >> >> Please look at these warnings, and if you see places to >> patch the code to eliminate the warnings, please submit patches >> and commit them if you can. > > Some time ago I tried to do something similar, but with gcc4.6 instead > of gcc4.9. > > The vast majority of warnings (1548) are "unused-but-set-variable" and > it may be worthwhile to just silence this warning, at least at low > WARNS levels. It has caught real errors but is quite noisy and can > cause quite a bit of churn. > > "inline" (count 515) is generally pure noise, and I think we should > disable it. It can be helpful to find certain types of performance > optimizations, but it should be opt-in. > > "strict-aliasing" (154) are likely all real bugs of some form. Very > few exist in contrib code, and it would be good to fix them. > > "Warning" (111) seem to be a mix of warnings, but mostly in contrib code. > > "maybe-uninitialized" (111) is often noisy, and in a spot check were > all false positives. > > "deprecated-declarations" (22) is all in contrib code > > Many of these are useful though and I've already fixed a few of the > bugs reported. > > Perhaps it would be useful to do a second run of this, but with a > modified share/mk to silence the most useless of these warnings? I just got a booting mips32 kernel using gcc-4.9.2, and boy are there a lot of warnings. I'm going to start fixing the ones I find - cleaner code is better code. Mostly. (I'd be happy with -Wall -Werror.) -adrian ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
Re: [Request for Help] Reducing gcc 4.9 compilation warnings
" On 18 April 2015 at 11:12, Craig Rodrigues wrote: > Hi, > > After the latest commits by members of freebsd-toolchain@ , > I have managed to compile latest CURRENT world and GENERIC > kernel on amd64 with an gcc 4.9 external toolchain by doing: > >pkg install devel/amd64-xtoolchain-gcc >cd /usr/src >sed -i "" -e 's/boot2//' sys/boot/i386/Makefile >make buildworld CROSS_TOOLCHAIN=amd64-gcc NO_WERROR=yes WERROR= >make buildkernel CROSS_TOOLCHAIN=amd64-gcc NO_WERROR=yes WERROR= > > > It was necessary to skip boot2 from building because of errors > reported here: > https://lists.freebsd.org/pipermail/freebsd-toolchain/2015-April/001658.html > > The boot2 compilation errors still need to be worked on. > > However, most other things compile with warnings. If folks are > interested in looking at the warnings, you can see them here: > > https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc4.9/warnings17 > > Please look at these warnings, and if you see places to > patch the code to eliminate the warnings, please submit patches > and commit them if you can. Some time ago I tried to do something similar, but with gcc4.6 instead of gcc4.9. The vast majority of warnings (1548) are "unused-but-set-variable" and it may be worthwhile to just silence this warning, at least at low WARNS levels. It has caught real errors but is quite noisy and can cause quite a bit of churn. "inline" (count 515) is generally pure noise, and I think we should disable it. It can be helpful to find certain types of performance optimizations, but it should be opt-in. "strict-aliasing" (154) are likely all real bugs of some form. Very few exist in contrib code, and it would be good to fix them. "Warning" (111) seem to be a mix of warnings, but mostly in contrib code. "maybe-uninitialized" (111) is often noisy, and in a spot check were all false positives. "deprecated-declarations" (22) is all in contrib code Many of these are useful though and I've already fixed a few of the bugs reported. Perhaps it would be useful to do a second run of this, but with a modified share/mk to silence the most useless of these warnings? -- Eitan Adler ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
[Request for Help] Reducing gcc 4.9 compilation warnings
Hi, After the latest commits by members of freebsd-toolchain@ , I have managed to compile latest CURRENT world and GENERIC kernel on amd64 with an gcc 4.9 external toolchain by doing: pkg install devel/amd64-xtoolchain-gcc cd /usr/src sed -i "" -e 's/boot2//' sys/boot/i386/Makefile make buildworld CROSS_TOOLCHAIN=amd64-gcc NO_WERROR=yes WERROR= make buildkernel CROSS_TOOLCHAIN=amd64-gcc NO_WERROR=yes WERROR= It was necessary to skip boot2 from building because of errors reported here: https://lists.freebsd.org/pipermail/freebsd-toolchain/2015-April/001658.html The boot2 compilation errors still need to be worked on. However, most other things compile with warnings. If folks are interested in looking at the warnings, you can see them here: https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc4.9/warnings17 Please look at these warnings, and if you see places to patch the code to eliminate the warnings, please submit patches and commit them if you can. clang is still going to be the default compiler in the base system, but it is nice to have FreeBSD compilable by multiple compilers. -- Craig ___ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
