2014-12-16 02:14:25

by Wang Nan

Subject: [PATCH] perf: fix building warning on ARM 32.

Commit 85c116a6c introduces asprintf() call and matches '%ld' to a u64
argument, which is incorrect on ARM.

CC /home/wn/util/srcline.o
util/srcline.c: In function 'get_srcline':
util/srcline.c:297:6: error: format '%ld' expects argument of type 'long int', but argument 4 has type 'u64' [-Werror=format]
cc1: all warnings being treated as errors
make[1]: *** [/home/wn/util/srcline.o] Error 1

Signed-off-by: Wang Nan <[email protected]>
---
tools/perf/util/srcline.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index e73b6a5..42cb642 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -294,7 +294,7 @@ out:
}
if (sym) {
if (asprintf(&srcline, "%s+%ld", show_sym ? sym->name : "",
- addr - sym->start) < 0)
+ (long int)(addr - sym->start)) < 0)
return SRCLINE_UNKNOWN;
} else if (asprintf(&srcline, "%s[%lx]", dso->short_name, addr) < 0)
return SRCLINE_UNKNOWN;
--
1.8.4

2014-12-16 04:49:01

by Namhyung Kim

Subject: Re: [PATCH] perf: fix building warning on ARM 32.

Hi Wang,

On Tue, Dec 16, 2014 at 10:10:10AM +0800, Wang Nan wrote:
> Commit 85c116a6c introduces asprintf() call and matches '%ld' to a u64
> argument, which is incorrect on ARM.
>
> CC /home/wn/util/srcline.o
> util/srcline.c: In function 'get_srcline':
> util/srcline.c:297:6: error: format '%ld' expects argument of type 'long int', but argument 4 has type 'u64' [-Werror=format]
> cc1: all warnings being treated as errors
> make[1]: *** [/home/wn/util/srcline.o] Error 1

Hmm.. shouldn't it be %PRIu64 instead?

Thanks,
Namhyung


>
> Signed-off-by: Wang Nan <[email protected]>
> ---
> tools/perf/util/srcline.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
> index e73b6a5..42cb642 100644
> --- a/tools/perf/util/srcline.c
> +++ b/tools/perf/util/srcline.c
> @@ -294,7 +294,7 @@ out:
> }
> if (sym) {
> if (asprintf(&srcline, "%s+%ld", show_sym ? sym->name : "",
> - addr - sym->start) < 0)
> + (long int)(addr - sym->start)) < 0)
> return SRCLINE_UNKNOWN;
> } else if (asprintf(&srcline, "%s[%lx]", dso->short_name, addr) < 0)
> return SRCLINE_UNKNOWN;
> --
> 1.8.4
>
> --
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> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/

2014-12-16 05:47:30

by Wang Nan

Subject: Re: [PATCH] perf: fix building warning on ARM 32.

On 2014/12/16 12:49, Namhyung Kim wrote:
> Hi Wang,
>
> On Tue, Dec 16, 2014 at 10:10:10AM +0800, Wang Nan wrote:
>> Commit 85c116a6c introduces asprintf() call and matches '%ld' to a u64
>> argument, which is incorrect on ARM.
>>
>> CC /home/wn/util/srcline.o
>> util/srcline.c: In function 'get_srcline':
>> util/srcline.c:297:6: error: format '%ld' expects argument of type 'long int', but argument 4 has type 'u64' [-Werror=format]
>> cc1: all warnings being treated as errors
>> make[1]: *** [/home/wn/util/srcline.o] Error 1
>
> Hmm.. shouldn't it be %PRIu64 instead?
>

It is a difference between two addresses, and I believe the value should not be very large.

Anyway, I'll follow your advise if you prefer to use %PRIu64.

In addition, addr is 'unsigned long addr', sym->start is 'u64', the type if
this expression is more or less obscure to readers. By investigating all caller
of get_srcline(), I find that the type of 'addr' should be 'u64', not 'unsigned long'.
So I'll post another patch which fixes param list of get_srcline() also.

Thanks.

> Thanks,
> Namhyung
>
>
>>
>> Signed-off-by: Wang Nan <[email protected]>
>> ---
>> tools/perf/util/srcline.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
>> index e73b6a5..42cb642 100644
>> --- a/tools/perf/util/srcline.c
>> +++ b/tools/perf/util/srcline.c
>> @@ -294,7 +294,7 @@ out:
>> }
>> if (sym) {
>> if (asprintf(&srcline, "%s+%ld", show_sym ? sym->name : "",
>> - addr - sym->start) < 0)
>> + (long int)(addr - sym->start)) < 0)
>> return SRCLINE_UNKNOWN;
>> } else if (asprintf(&srcline, "%s[%lx]", dso->short_name, addr) < 0)
>> return SRCLINE_UNKNOWN;
>> --
>> 1.8.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to [email protected]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/