Le 07/09/2018 à 15:58, Peter Zijlstra a écrit :
On Fri, Sep 07, 2018 at 01:50:18PM +0000, Christophe Leroy wrote:
On 09/07/2018 01:42 PM, Peter Zijlstra wrote:
On Fri, Sep 07, 2018 at 01:27:19PM +0000, Christophe Leroy wrote:
On PPC32, enums are 32 bits, so __PERF_SAMPLE_CALLCHAIN_EARLY is
out of scope. The following sparse warning is encountered:
CHECK arch/powerpc/kernel/process.c
./include/uapi/linux/perf_event.h:147:56: warning: cast truncates bits from
constant value (8000000000000000 becomes 0)
Urgh... what compiler is that? I've not seen anything like that from the
build bots.
[root@pc16082vm linux-powerpc]# sparse --version
0.5.2
[root@pc16082vm linux-powerpc]# ppc-linux-gcc --version
ppc-linux-gcc (GCC) 5.4.0
Ah, that's a sparse warning. But does your GCC agree? The thing is,
sparse uses the C enum spec, but I suspect GCC uses the C++ enum spec
and it all works fine.
Ah yes, it seems that GCC is happy. So sparse should be fixed instead ?
Anyway, is it really correct to put this constant inside that enum,
after PERF_SAMPLE_MAX ?
Christophe