[patch] perf_counter tools: fix libbfd detection for systems with libz dependency

[Mike Galbraith <efault@gmx.de>]

perf_counter tools: fix libbfd detection for systems with libz dependency

Due to a libz dependency in some distro's binutils package, demangle
support isn't compiled in despite the necessary libraries being available.
Fix this by adding a -lz link test to the dependency detection rules.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>

 tools/perf/Makefile |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 1916e44..60411e9 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -387,10 +387,14 @@ else
 
 	has_bfd_iberty := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) -lbfd -liberty > /dev/null 2>&1 && echo y")
 
+	has_bfd_iberty_z := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) -lbfd -liberty -lz > /dev/null 2>&1 && echo y")
+
 	ifeq ($(has_bfd),y)
 		EXTLIBS += -lbfd
 	else ifeq ($(has_bfd_iberty),y)
 		EXTLIBS += -lbfd -liberty
+	else ifeq ($(has_bfd_iberty_z),y)
+		EXTLIBS += -lbfd -liberty -lz
 	else
 		msg := $(warning No bfd.h/libbfd found, install binutils-dev[el] to gain symbol demangling)
 		BASIC_CFLAGS += -DNO_DEMANGLE