[PATCH] perf tools: Fix compilation on powerpc

From: Jiri Olsa
Date: Tue Sep 28 2021 - 15:53:02 EST


Got following build fail on powerpc:

CC arch/powerpc/util/skip-callchain-idx.o
In function ‘check_return_reg’,
inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
in a region of size 64 [-Werror=stringop-overflow=]
54 | result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
In file included from /usr/include/elfutils/libdwfl.h:32,
from arch/powerpc/util/skip-callchain-idx.c:10:
/usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
| ^~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

The dwarf_frame_register args changed with [1],
Updating ops_mem accordingly.

[1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=5621fe5443da23112170235dd5cac161e5c75e65

Cc: Mark Wielaard <mjw@xxxxxxxxxx>
Cc: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/arch/powerpc/util/skip-callchain-idx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
index 3018a054526a..20cd6244863b 100644
--- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c
+++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c
@@ -45,7 +45,7 @@ static const Dwfl_Callbacks offline_callbacks = {
*/
static int check_return_reg(int ra_regno, Dwarf_Frame *frame)
{
- Dwarf_Op ops_mem[2];
+ Dwarf_Op ops_mem[3];
Dwarf_Op dummy;
Dwarf_Op *ops = &dummy;
size_t nops;
--
2.31.1