[PATCH -tip] perf probe: Check older elfutils and set NO_DWARF

[Masami Hiramatsu <mhiramat@redhat.com>]

Check whether elfutils is older than 0.138 (from which version checking
routine has been introduced). And if so, set NO_DWARF because it is hard
to check the API dependency without version checking.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Reported-by: Robert Richter <robert.richter@amd.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
---

 tools/perf/Makefile |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 0ef5cfe..b28bb73 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -506,8 +506,8 @@ PERFLIBS = $(LIB_FILE)
 -include config.mak
 
 ifndef NO_DWARF
-ifneq ($(shell sh -c "(echo '\#include <dwarf.h>'; echo '\#include <libdw.h>'; echo 'int main(void) { Dwarf *dbg; dbg = dwarf_begin(0, DWARF_C_READ); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -I/usr/include/elfutils -ldw -lelf -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
-	msg := $(warning No libdw.h found or old libdw.h found, disables dwarf support. Please install elfutils-devel/libdw-dev);
+ifneq ($(shell sh -c "(echo '\#include <dwarf.h>'; echo '\#include <libdw.h>'; echo '\#include <version.h>'; echo '\#ifndef _ELFUTILS_PREREQ'; echo '\#error'; echo '\#endif'; echo 'int main(void) { Dwarf *dbg; dbg = dwarf_begin(0, DWARF_C_READ); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -I/usr/include/elfutils -ldw -lelf -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
+	msg := $(warning No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev);
 	NO_DWARF := 1
 endif # Dwarf support
 endif # NO_DWARF


-- 
Masami Hiramatsu
e-mail: mhiramat@redhat.com