lkml.org 
[lkml]   [2018]   [Jun]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2 2/3] perf script python: Add more PMU fields
From
Date


On 6/7/2018 2:36 AM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Jun 01, 2018 at 05:01:02PM +0800, Jin Yao escreveu:
>
> <SNIP>
>
>> +static int get_symoff(struct symbol *sym, struct addr_location *al,
>> + bool print_off, char *bf, int size)
>> +{
>> + unsigned long offset;
>> +
>> + if (!sym || !sym->name)
>> + return scnprintf(bf, size, "%s", "[unknown]");
>
> 52 54.22 ubuntu:17.04 : FAIL gcc (Ubuntu 6.3.0-12ubuntu2) 6.3.0 20170406
>
> CC /tmp/build/perf/util/scripting-engines/trace-event-python.o
> util/scripting-engines/trace-event-python.c:534:20: error: address of array 'sym->name' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion]
> if (!sym || !sym->name)
> ~~~~~~^~~~
> 1 error generated.
> mv: cannot stat '/tmp/build/perf/util/scripting-engines/.trace-event-python.o.tmp': No such file or directory
> /git/linux/tools/build/Makefile.build:96: recipe for target '/tmp/build/perf/util/scripting-engines/trace-event-python.o' failed
> make[5]: *** [/tmp/build/perf/util/scripting-engines/trace-event-python.o] Error 1
>
> Because:
>
> struct symbol {
> struct rb_node rb_node;
> u64 start;
> u64 end;
> u16 namelen;
> <SNIP>
> char name[0];
> };
>
> It sym->name is not a pointer, in symbol's constructor we have:
>
> struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
> {
> size_t namelen = strlen(name) + 1;
> struct symbol *sym = calloc(1, (symbol_conf.priv_size +
> sizeof(*sym) + namelen));
> if (sym == NULL)
> return NULL;
> <SNIP>
> sym->namelen = namelen - 1;
> memcpy(sym->name, name, namelen);
>
> return sym;
> }
>
> So it is at least 1 char long, the test above should be:
>
> if (!sym || !sym->name[0])
> return scnprintf(bf, size, "%s", "[unknown]");
>
> I'm fixing this up here.
>
> - Arnaldo
>

Oh, yes, my mistake, very sorry about that.

Thanks for helping me to fix this.

Thanks
Jin Yao

\
 
 \ /
  Last update: 2018-06-07 03:01    [W:0.107 / U:0.728 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site