[PATCH 4.4 11/40] perf tools: Fix build failure on perl script context

From: Greg Kroah-Hartman
Date: Mon Nov 06 2017 - 04:58:48 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Namhyung Kim <namhyung@xxxxxxxxxx>

commit b581c01fff646b5075d65359c8667de9c667da9e upstream.

On my Archlinux machine, perf faild to build like below:

CC scripts/perl/Perf-Trace-Util/Context.o
In file included from /usr/lib/perl5/core/perl/CORE/perl.h:3905:0,
from Context.xs:23:
/usr/lib/perl5/core/perl/CORE/inline.h: In function :
/usr/lib/perl5/core/perl/CORE/cop.h:612:13: warning: declaration of 'av'
shadows a previous local [-Werror-shadow]
AV *av =3D GvAV(PL_defgv);
^
/usr/lib/perl5/core/perl/CORE/inline.h:526:5: note: in expansion of
macro 'CX_POP_SAVEARRAY'
CX_POP_SAVEARRAY(cx);
^~~~~~~~~~~~~~~~
In file included from /usr/lib/perl5/core/perl/CORE/perl.h:5853:0,
from Context.xs:23:
/usr/lib/perl5/core/perl/CORE/inline.h:518:9: note:
shadowed declaration is here
AV *av;
^~

What I did to fix is adding '-Wno-shadow' as the error message said it's
the cause of the failure. Since it's from the perl (not perf) code
base, we don't have the control so I just wanted to ignore the warning
when compiling perl scripting code.

Committer note:

This also fixes the build on Fedora Rawhide.

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20160802024317.31725-1-namhyung@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Tuomas Tynkkynen <tuomas.tynkkynen@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
tools/perf/scripts/perl/Perf-Trace-Util/Build | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/tools/perf/scripts/perl/Perf-Trace-Util/Build
+++ b/tools/perf/scripts/perl/Perf-Trace-Util/Build
@@ -1,3 +1,5 @@
libperf-y += Context.o

-CFLAGS_Context.o += $(PERL_EMBED_CCOPTS) -Wno-redundant-decls -Wno-strict-prototypes -Wno-unused-parameter -Wno-nested-externs -Wno-undef -Wno-switch-default
+CFLAGS_Context.o += $(PERL_EMBED_CCOPTS) -Wno-redundant-decls -Wno-strict-prototypes
+CFLAGS_Context.o += -Wno-unused-parameter -Wno-nested-externs -Wno-undef
+CFLAGS_Context.o += -Wno-switch-default -Wno-shadow