Re: [PATCH 00/12] libperf: Add events to perf/event.h

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

Em Mon, Aug 26, 2019 at 07:14:19PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Aug 26, 2019 at 06:58:52PM +0200, Jiri Olsa escreveu:
> > On Mon, Aug 26, 2019 at 01:18:49PM -0300, Arnaldo Carvalho de Melo wrote:
> > 
> > SNIP
> > 
> > > [perfbuilder@490c2c7bdaab ~]$ grep 'printf("lost' /tmp/build/perf/builtin-sched.i
> > >  printf("lost %" "l" "ll""u" " events on cpu %d\n", event->lost.lost, sample->cpu);
> > > [perfbuilder@490c2c7bdaab ~]$
> > > 
> > > And if we do this on a fedora:30 x86_64:
> > > 
> > > $ make -C tools/perf O=/tmp/build/perf /tmp/build/perf/builtin-sched.i
> > > [acme@quaco perf]$ grep -A4 'printf("lost' /tmp/build/perf/builtin-sched.i
> > >  printf("lost %" "l" 
> > > # 2646 "builtin-sched.c" 3 4
> > >                 "l" "u" 
> > > # 2646 "builtin-sched.c"
> > >                          " events on cpu %d\n", event->lost.lost, sample->cpu);
> > > [acme@quaco perf]$
> > > 
> > > I.e. on 32-bit arches we shouldn't add that extra "l", right?
> > 
> > hum, I guess we could #ifdef it 64/32 bits
> 
> I tried to figure out how to fix this better, but the int-ll64.h versus
> int-l64.h versus how __u64 is defined got me confused and I ended up
> with:
> 
> #if __WORDSIZE == 64

Make that:

#ifdef __LP64__ to build on Alpine/musl libc.

- Arnaldo

> /*
>  * /usr/include/inttypes.h uses just 'lu' for PRIu64, but we end up defining
>  * __u64 as long long unsigned int, and then -Werror=format= kicks in and
>  * complains of the mismatched types, so use these two special extra PRI
>  * macros to overcome that.
>  */
> #define PRI_lu64 "l" PRIu64
> #define PRI_lx64 "l" PRIx64
> #else
> #define PRI_lu64 PRIu64
> #define PRI_lx64 PRIx64
> #endif
> 
> Builds in all the containers I have, 32-bit, 64-bit, old gccs/clangs,
> new ones, uclibc, musl libc, glibc, etc
>  
> > > 
> > > I bet the build for the mips/mipsel will fail too, lemme see... Yeah,
> > > both failed:
> > > 
> > > 
> >> [root@quaco ~]# grep -m1 -A6 -- -Werror=format=  dm.log/debian\:experimental-x-mips
> > > builtin-sched.c:2646:9: error: unknown conversion type character 'l' in format [-Werror=format=]
> > >   printf("lost %" PRI_lu64 " events on cpu %d\n", event->lost.lost, sample->cpu);
> > >          ^~~~~~~~
> > > In file included from builtin-sched.c:31:
> > > /usr/mips-linux-gnu/include/inttypes.h:47:28: note: format string is defined here
> > >  #  define __PRI64_PREFIX "ll"
> > >                             ^
> > > [root@quaco ~]#
> > > 
> > > [root@quaco ~]# grep -m1 -A6 -- -Werror=format=  dm.log/debian\:experimental-x-mipsel
> > > builtin-sched.c:2646:9: error: unknown conversion type character 'l' in format [-Werror=format=]
> > >   printf("lost %" PRI_lu64 " events on cpu %d\n", event->lost.lost, sample->cpu);
> > >          ^~~~~~~~
> > > In file included from builtin-sched.c:31:
> > > /usr/mipsel-linux-gnu/include/inttypes.h:47:28: note: format string is defined here
> > >  #  define __PRI64_PREFIX "ll"
> > >                             ^
> > > [root@quaco ~]#
> > > 
> > > And also on a uclibc ARC arch container:
> > > 
> > > [root@quaco ~]# grep -m1 -A6 -- -Werror=format=  dm.log/fedora\:24-x-ARC-uClibc
> > > builtin-sched.c:2646:9: error: unknown conversion type character 'l' in format [-Werror=format=]
> > >   printf("lost %" PRI_lu64 " events on cpu %d\n", event->lost.lost, sample->cpu);
> > >          ^~~~~~~~
> > > In file included from builtin-sched.c:31:0:
> > > /arc_gnu_2017.09-rc2_prebuilt_uclibc_le_arc700_linux_install/arc-snps-linux-uclibc/sysroot/usr/include/inttypes.h:47:28: note: format string is defined here
> > >  #  define __PRI64_PREFIX "ll"
> > >                             ^
> > > [root@quaco ~]#
> > > 
> > > The _fix_ will come after lunch :)
> > 
> > thanks ;-)
> > 
> > jirka
> 
> -- 
> 
> - Arnaldo

-- 

- Arnaldo