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

[Arnaldo Carvalho de Melo]

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
/*
 * /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