* [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE @ 2011-04-10 2:09 Valentin Ochs 2011-04-10 3:34 ` Arnaud Lacombe 0 siblings, 1 reply; 6+ messages in thread From: Valentin Ochs @ 2011-04-10 2:09 UTC (permalink / raw) Cc: Michal Marek, Roman Zippel, trivial, linux-kbuild, linux-kernel The three patched files use PATH_MAX without defining the required _POSIX_C_SOURCE feature test macro. This prevents compilation with the musl libc. The patch applies to 2.6.38.2. Changes since v1: - fix scripts/kconfig/lex.zconf.c_shipped - fix scripts/kconfig/mconf.c Sorry about the incomplete patch I sent a few hours ago, it won't happen again. :) Best regards, Valentin Signed-off-by: Valentin Ochs <a@0au.de> --- --- a/scripts/basic/fixdep.c +++ b/scripts/basic/fixdep.c @@ -102,7 +102,7 @@ * through arch/um/include/uml-config.h; this fixdep "bug" makes sure that * those files will have correct dependencies. */ +#define _POSIX_C_SOURCE 200809L #include <sys/types.h> #include <sys/stat.h> #include <sys/mman.h> --- a/scripts/kconfig/lex.zconf.c_shipped +++ b/scripts/kconfig/lex.zconf.c_shipped @@ -35,6 +35,7 @@ /* First, we deal with platform-specific or compiler-specific issues. */ /* begin standard C headers. */ +#define _POSIX_C_SOURCE 200809L #include <stdio.h> #include <string.h> #include <errno.h> --- a/scripts/kconfig/mconf.c +++ b/scripts/kconfig/mconf.c @@ -7,7 +7,7 @@ * * i18n, 2005, Arnaldo Carvalho de Melo <acme@conectiva.com.br> */ +#define _POSIX_C_SOURCE 200809L #include <ctype.h> #include <errno.h> #include <fcntl.h> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE 2011-04-10 2:09 [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE Valentin Ochs @ 2011-04-10 3:34 ` Arnaud Lacombe 2011-04-10 14:31 ` Valentin Ochs 0 siblings, 1 reply; 6+ messages in thread From: Arnaud Lacombe @ 2011-04-10 3:34 UTC (permalink / raw) To: Valentin Ochs Cc: Michal Marek, Roman Zippel, trivial, linux-kbuild, linux-kernel Hi, On Sat, Apr 9, 2011 at 10:09 PM, Valentin Ochs <a@0au.de> wrote: > The three patched files use PATH_MAX without defining the required > _POSIX_C_SOURCE feature test macro. This prevents compilation with the > musl libc. The patch applies to 2.6.38.2. > > Changes since v1: > - fix scripts/kconfig/lex.zconf.c_shipped this file is autogenerated from zconf.l, which should be updated as well. I'm not sure how you searched for PATH_MAX, but you're still missing `confdata.c' and `nconf.c'. I had a quick look to different libc implementation, glibc and uClibc default to _POSIX_C_SOURCE == 200112L, FreeBSD >8.0 defaults to 200809L for >8.0, FreeBSD 7.x to 200112L. None of these seems to requires _POSIX_C_SOURCE to define PATH_MAX, so I'm not certain of the requirement of the change. Moreover, musl libc seems to be really young (first public version less than two month old), and still marked "alpha", not sure if its the best time to start fixing things. - Arnaud > - fix scripts/kconfig/mconf.c > > Sorry about the incomplete patch I sent a few hours ago, it won't happen > again. :) > > Best regards, > Valentin > > Signed-off-by: Valentin Ochs <a@0au.de> > --- > --- a/scripts/basic/fixdep.c > +++ b/scripts/basic/fixdep.c > @@ -102,7 +102,7 @@ > * through arch/um/include/uml-config.h; this fixdep "bug" makes sure that > * those files will have correct dependencies. > */ > > +#define _POSIX_C_SOURCE 200809L > #include <sys/types.h> > #include <sys/stat.h> > #include <sys/mman.h> > --- a/scripts/kconfig/lex.zconf.c_shipped > +++ b/scripts/kconfig/lex.zconf.c_shipped > @@ -35,6 +35,7 @@ > /* First, we deal with platform-specific or compiler-specific issues. */ > > /* begin standard C headers. */ > +#define _POSIX_C_SOURCE 200809L > #include <stdio.h> > #include <string.h> > #include <errno.h> > --- a/scripts/kconfig/mconf.c > +++ b/scripts/kconfig/mconf.c > @@ -7,7 +7,7 @@ > * > * i18n, 2005, Arnaldo Carvalho de Melo <acme@conectiva.com.br> > */ > > +#define _POSIX_C_SOURCE 200809L > #include <ctype.h> > #include <errno.h> > #include <fcntl.h> > -- > To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE 2011-04-10 3:34 ` Arnaud Lacombe @ 2011-04-10 14:31 ` Valentin Ochs 2011-04-19 9:54 ` Michal Marek 0 siblings, 1 reply; 6+ messages in thread From: Valentin Ochs @ 2011-04-10 14:31 UTC (permalink / raw) Cc: Michal Marek, Roman Zippel, trivial, linux-kbuild, linux-kernel Thanks for the answer! On Sat, Apr 09, 2011 at 11:34:00PM -0400, Arnaud Lacombe wrote: > Hi, > > On Sat, Apr 9, 2011 at 10:09 PM, Valentin Ochs <a@0au.de> wrote: > > The three patched files use PATH_MAX without defining the required > > _POSIX_C_SOURCE feature test macro. This prevents compilation with the > > musl libc. The patch applies to 2.6.38.2. > > > > Changes since v1: > > - fix scripts/kconfig/lex.zconf.c_shipped > this file is autogenerated from zconf.l, which should be updated as > well. I'm not sure how you searched for PATH_MAX, but you're still > missing `confdata.c' and `nconf.c'. To be honest, I only fixed the files that did not compile when I ran 'make menuconfig'. It didn't even occur to me that it could be in other files as well. I've grepped for it now, and there are lots of other files that use PATH_MAX - it's probably safe to assume that kernel/* and fs/* use the limits.h in include/linux. What about the files in tools/*? Would it be preferable to have the makefile define _POSIX_C_SOURCE, or is that too hackish? > I had a quick look to different libc implementation, glibc and uClibc > default to _POSIX_C_SOURCE == 200112L, FreeBSD >8.0 defaults to > 200809L for >8.0, FreeBSD 7.x to 200112L. I got the value I used from the Open Group System Interfaces specification, but the musl author said that 200112L would be fine too. > None of these seems to requires _POSIX_C_SOURCE to define PATH_MAX, so > I'm not certain of the requirement of the change. While I don't want to appear like a language lawyer, the specification says that 'all symbols required by POSIX.1-2008 to appear when the header is included shall be made visible' when an application defines _POSIX_C_SOURCE. I guess the musl author interprets that as 'if you don't define the feature test macros, you're not getting PATH_MAX.' This does not seem to be incorrect behaviour to me. > Moreover, musl libc seems to be really young (first public version > less than two month old), and still marked "alpha", not sure if its > the best time to start fixing things. I don't think that the musl headers are going to change much in that regard, and the patch only changes the files to better conform to POSIX. But if you don't want to apply the patch now, I can resubmit it in a few months and just ask the musl author to put it on the musl website for now. Best regards, Valentin > - Arnaud > > > - fix scripts/kconfig/mconf.c > > > > Sorry about the incomplete patch I sent a few hours ago, it won't > > happen again. :) ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE 2011-04-10 14:31 ` Valentin Ochs @ 2011-04-19 9:54 ` Michal Marek 2011-04-19 17:03 ` Arnaud Lacombe 0 siblings, 1 reply; 6+ messages in thread From: Michal Marek @ 2011-04-19 9:54 UTC (permalink / raw) To: Valentin Ochs; +Cc: Roman Zippel, trivial, linux-kbuild, linux-kernel On 10.4.2011 16:31, Valentin Ochs wrote: > On Sat, Apr 09, 2011 at 11:34:00PM -0400, Arnaud Lacombe wrote: >> On Sat, Apr 9, 2011 at 10:09 PM, Valentin Ochs <a@0au.de> wrote: >>> The three patched files use PATH_MAX without defining the required >>> _POSIX_C_SOURCE feature test macro. This prevents compilation with the >>> musl libc. The patch applies to 2.6.38.2. >>> >>> Changes since v1: >>> - fix scripts/kconfig/lex.zconf.c_shipped >> this file is autogenerated from zconf.l, which should be updated as >> well. I'm not sure how you searched for PATH_MAX, but you're still >> missing `confdata.c' and `nconf.c'. Yes, please fix the bison parser and run make GENERATE_PARSER=1 menuconfig to update the *_shipped files. >> I had a quick look to different libc implementation, glibc and uClibc >> default to _POSIX_C_SOURCE == 200112L, FreeBSD >8.0 defaults to >> 200809L for >8.0, FreeBSD 7.x to 200112L. > > I got the value I used from the Open Group System Interfaces > specification, but the musl author said that 200112L would be fine too. I suggest you use 200112L, so that it is a nop for glibc/uClibc builds. Please also accompany it with a /* for PATH_MAX */ comment or so. > >> None of these seems to requires _POSIX_C_SOURCE to define PATH_MAX, so >> I'm not certain of the requirement of the change. > > While I don't want to appear like a language lawyer, the specification > says that 'all symbols required by POSIX.1-2008 to appear when the > header is included shall be made visible' when an application defines > _POSIX_C_SOURCE. I guess the musl author interprets that as 'if you > don't define the feature test macros, you're not getting PATH_MAX.' This > does not seem to be incorrect behaviour to me. While I don't completely understand the motivation for such super-pedantic libc implementation, the fact is that POSIX says one should define this macro, so let's define it, it does not hurt us. Michal ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE 2011-04-19 9:54 ` Michal Marek @ 2011-04-19 17:03 ` Arnaud Lacombe 2011-04-19 17:07 ` Arnaud Lacombe 0 siblings, 1 reply; 6+ messages in thread From: Arnaud Lacombe @ 2011-04-19 17:03 UTC (permalink / raw) To: Michal Marek Cc: Valentin Ochs, Roman Zippel, trivial, linux-kbuild, linux-kernel Hi, On Tue, Apr 19, 2011 at 5:54 AM, Michal Marek <mmarek@suse.cz> wrote: > On 10.4.2011 16:31, Valentin Ochs wrote: >> On Sat, Apr 09, 2011 at 11:34:00PM -0400, Arnaud Lacombe wrote: >>> On Sat, Apr 9, 2011 at 10:09 PM, Valentin Ochs <a@0au.de> wrote: >>>> The three patched files use PATH_MAX without defining the required >>>> _POSIX_C_SOURCE feature test macro. This prevents compilation with the >>>> musl libc. The patch applies to 2.6.38.2. >>>> >>>> Changes since v1: >>>> - fix scripts/kconfig/lex.zconf.c_shipped >>> this file is autogenerated from zconf.l, which should be updated as >>> well. I'm not sure how you searched for PATH_MAX, but you're still >>> missing `confdata.c' and `nconf.c'. > > Yes, please fix the bison parser and run make GENERATE_PARSER=1 > menuconfig to update the *_shipped files. > > >>> I had a quick look to different libc implementation, glibc and uClibc >>> default to _POSIX_C_SOURCE == 200112L, FreeBSD >8.0 defaults to >>> 200809L for >8.0, FreeBSD 7.x to 200112L. >> >> I got the value I used from the Open Group System Interfaces >> specification, but the musl author said that 200112L would be fine too. > > I suggest you use 200112L, so that it is a nop for glibc/uClibc builds. > Please also accompany it with a /* for PATH_MAX */ comment or so. > no it's not. Defining _POSIX_C_SOURCE disables automatic definition of a few features macros, see below. >> >>> None of these seems to requires _POSIX_C_SOURCE to define PATH_MAX, so >>> I'm not certain of the requirement of the change. >> >> While I don't want to appear like a language lawyer, the specification >> says that 'all symbols required by POSIX.1-2008 to appear when the >> header is included shall be made visible' when an application defines >> _POSIX_C_SOURCE. I guess the musl author interprets that as 'if you >> don't define the feature test macros, you're not getting PATH_MAX.' This >> does not seem to be incorrect behaviour to me. > > While I don't completely understand the motivation for such > super-pedantic libc implementation, the fact is that POSIX says one > should define this macro, so let's define it, it does not hurt us. > If we go that way, we should at least: diff --git a/Makefile b/Makefile index d6592b6..0490413 100644 --- a/Makefile +++ b/Makefile @@ -233,7 +233,7 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \ HOSTCC = gcc HOSTCXX = g++ -HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer +HOSTCFLAGS = -D_POSIX_C_SOURCE=200112L -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer HOSTCXXFLAGS = -O2 at best: index d6592b6..0490413 100644 --- a/Makefile +++ b/Makefile @@ -233,7 +233,7 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \ HOSTCC = gcc HOSTCXX = g++ -HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer +HOSTCFLAGS = --std=c99 -D_POSIX_C_SOURCE=200112L -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer HOSTCXXFLAGS = -O2 Both introduces new warnings with the glibc shipped with fedora 14 relating to strdup(3) needing one of: _SVID_SOURCE, _BSD_SOURCE, _XOPEN_SOURCE, _POSIX_C_SOURCE>=200809L (for __USE_XOPEN2K8). -D_POSIX_C_SOURCE=200809L do not generate more warning, at least on my host. Just for reference, the second change fails anyway as `nconf' uses GNU extension of C99. - Arnaud > Michal > -- > To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE 2011-04-19 17:03 ` Arnaud Lacombe @ 2011-04-19 17:07 ` Arnaud Lacombe 0 siblings, 0 replies; 6+ messages in thread From: Arnaud Lacombe @ 2011-04-19 17:07 UTC (permalink / raw) To: Michal Marek Cc: Valentin Ochs, Roman Zippel, trivial, linux-kbuild, linux-kernel Hi, On Tue, Apr 19, 2011 at 1:03 PM, Arnaud Lacombe <lacombar@gmail.com> wrote: > diff --git a/Makefile b/Makefile > index d6592b6..0490413 100644 > --- a/Makefile > +++ b/Makefile > @@ -233,7 +233,7 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then > echo $$BASH; \ > > HOSTCC = gcc > HOSTCXX = g++ > -HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 > -fomit-frame-pointer > +HOSTCFLAGS = -D_POSIX_C_SOURCE=200112L -Wall -Wmissing-prototypes > -Wstrict-prototypes -O2 -fomit-frame-pointer > HOSTCXXFLAGS = -O2 > Sorry, gmail wrapped long lines, the relevant part is only: HOSTCFLAGS+= -D_POSIX_C_SOURCE=200112L - Arnaud ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2011-04-19 17:07 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2011-04-10 2:09 [PATCH v2] kconfig/kbuild: define _POSIX_C_SOURCE Valentin Ochs 2011-04-10 3:34 ` Arnaud Lacombe 2011-04-10 14:31 ` Valentin Ochs 2011-04-19 9:54 ` Michal Marek 2011-04-19 17:03 ` Arnaud Lacombe 2011-04-19 17:07 ` Arnaud Lacombe
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