Re: [PATCH v1 4/6] perf build: Disable fewer flex warnings

[Arnaldo Carvalho de Melo]

Em Fri, Jul 28, 2023 at 09:50:59AM +0100, James Clark escreveu:
> 
> 
> On 28/07/2023 07:49, Ian Rogers wrote:
> > If flex is version 2.6.4, reduce the number of flex C warnings
> > disabled. Earlier flex versions have all C warnings disabled.
> 
> Hi Ian,
> 
> I get a build error with either this one or the bison warning change:
> 
>   $ make LLVM=1 -C tools/perf NO_BPF_SKEL=1 DEBUG=1
> 
>   util/pmu-bison.c:855:9: error: variable 'perf_pmu_nerrs' set but not
> used [-Werror,-Wunused-but-set-variable]
>     int yynerrs = 0;
> 
> I tried a clean build which normally fixes these kind of bison errors.
> Let me know if you need any version info.

Trying to build it with the command line above I get:

  CC      util/expr.o
  CC      util/parse-events.o
  CC      util/parse-events-flex.o
util/parse-events-flex.c:7503:13: error: misleading indentation; statement is not part of the previous 'if' [-Werror,-Wmisleading-indentation]
            if ( ! yyg->yy_state_buf )
            ^
util/parse-events-flex.c:7501:9: note: previous statement is here
        if ( ! yyg->yy_state_buf )
        ^
1 error generated.
make[4]: *** [/var/home/acme/git/perf-tools-next/tools/build/Makefile.build:97: util/parse-events-flex.o] Error 1
make[4]: *** Waiting for unfinished jobs....
  LD      util/scripting-engines/perf-in.o
make[3]: *** [/var/home/acme/git/perf-tools-next/tools/build/Makefile.build:140: util] Error 2
make[2]: *** [Makefile.perf:682: perf-in.o] Error 2
make[2]: *** Waiting for unfinished jobs....
  CC      pmu-events/pmu-events.o
  LD      pmu-events/pmu-events-in.o
make[1]: *** [Makefile.perf:242: sub-make] Error 2
make: *** [Makefile:70: all] Error 2

⬢[acme@toolbox perf-tools-next]$ clang --version
clang version 14.0.5 (Fedora 14.0.5-2.fc36)
Target: x86_64-redhat-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
⬢[acme@toolbox perf-tools-next]$