perf tools: Fix fallback to cplus_demangle() when bfd_demangle() is not available

In old binutils we can't access bfd_demangle(), use
cplus_demangle() just like oprofile.

Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Luis Claudio R. Gonçalves <[e-mail]>
Cc: H. Peter Anvin <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Mike Galbraith <[e-mail]>
Cc: Frédéric Weisbecker <[e-mail]>
LKML-Reference: <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>

tools/perf/Makefile

···
 ifdef NO_DEMANGLE
 	BASIC_CFLAGS += -DNO_DEMANGLE
 else
-
 	has_bfd := $(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 > /dev/null 2>&1 && echo y")
-
-	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
+		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 $(ALL_LDFLAGS) -lbfd -liberty > /dev/null 2>&1 && echo y")
+		ifeq ($(has_bfd_iberty),y)
+			EXTLIBS += -lbfd -liberty
+		else
+			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_iberty_z),y)
+				EXTLIBS += -lbfd -liberty -lz
+			else
+				has_cplus_demangle := $(shell sh -c "(echo 'extern char *cplus_demangle(const char *, int);'; echo 'int main(void) { cplus_demangle(0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) -liberty > /dev/null 2>&1 && echo y")
+				ifeq ($(has_cplus_demangle),y)
+					EXTLIBS += -liberty
+					BASIC_CFLAGS += -DHAVE_CPLUS_DEMANGLE
+				else
+					msg := $(warning No bfd.h/libbfd found, install binutils-dev[el] to gain symbol demangling)
+					BASIC_CFLAGS += -DNO_DEMANGLE
+				endif
+			endif
+		endif
 	endif
 endif
 

tools/perf/util/symbol.c

···
 #include <gelf.h>
 #include <elf.h>
 
-#ifndef NO_DEMANGLE
-#include <bfd.h>
-#else
-static inline
-char *bfd_demangle(void __used *v, const char __used *c, int __used i)
-{
-	return NULL;
-}
-#endif
-
 const char *sym_hist_filter;
-
-#ifndef DMGL_PARAMS
-#define DMGL_PARAMS      (1 << 0)       /* Include function args */
-#define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */
-#endif
 
 enum dso_origin {
 	DSO__ORIG_KERNEL = 0,

tools/perf/util/symbol.h

···
 #include <linux/rbtree.h>
 #include "module.h"
 
+#ifdef HAVE_CPLUS_DEMANGLE
+extern char *cplus_demangle(const char *, int);
+
+static inline char *bfd_demangle(void __used *v, const char *c, int i)
+{
+	return cplus_demangle(c, i);
+}
+#else
+#ifdef NO_DEMANGLE
+static inline char *bfd_demangle(void __used *v, const char __used *c,
+				 int __used i)
+{
+	return NULL;
+}
+#else
+#include <bfd.h>
+#endif
+#endif
+
+#ifndef DMGL_PARAMS
+#define DMGL_PARAMS      (1 << 0)       /* Include function args */
+#define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */
+#endif
+
 struct symbol {
 	struct rb_node	rb_node;
 	u64		start;