perf: Auto-detect libbfd

Since the C++ demangling isn't needed for everybody and
bfd/iberty aren't widely/easily available on all machines, make
it optional.

It also allows you to forcefully disable demangling by using
NO_DEMANGLE=1 and otherwise tries to detect libbfd/libiberty
combinations that result in a compiling demangler.

Reported-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
LKML-Reference: <20090801082048.GX12579@kernel.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-08-05 14:05:16 +02:00 committed by Ingo Molnar
parent 114cfab222
commit 2cdbc46d7b
2 changed files with 26 additions and 1 deletions

View file

@ -345,7 +345,6 @@ BUILTIN_OBJS += builtin-stat.o
BUILTIN_OBJS += builtin-top.o
PERFLIBS = $(LIB_FILE)
EXTLIBS = -lbfd -liberty
#
# Platform specific tweaks
@ -374,6 +373,23 @@ ifeq ($(uname_S),Darwin)
PTHREAD_LIBS =
endif
ifdef NO_DEMANGLE
BASIC_CFLAGS += -DNO_DEMANGLE
else
has_bfd := $(shell sh -c "(echo '\#include <stdio.h>'; echo '\#include <bfd.h>'; echo '\#ifndef DMGL_PARAMS'; echo '\#define DMGL_PARAMS (1 << 0)'; echo '\#define DMGL_ANSI (1 << 1)'; echo '\#endif'; echo 'int main(int argc, char **argv) { bfd_demangle(NULL, argv[0], DMGL_PARAMS | DMGL_ANSI); return 0; }') | gcc -x c - -lbfd > /dev/null 2>&1 && echo y")
has_bfd_iberty := $(shell sh -c "(echo '\#include <stdio.h>'; echo '\#include <bfd.h>'; echo '\#ifndef DMGL_PARAMS'; echo '\#define DMGL_PARAMS (1 << 0)'; echo '\#define DMGL_ANSI (1 << 1)'; echo '\#endif'; echo 'int main(int argc, char **argv) { bfd_demangle(NULL, argv[0], DMGL_PARAMS | DMGL_ANSI); return 0; }') | gcc -x c - -lbfd -liberty > /dev/null 2>&1 && echo y")
ifeq ($(has_bfd),y)
EXTLIBS += -lbfd
else ifeq ($(has_bfd_iberty),y)
EXTLIBS += -lbfd -liberty
else
BASIC_CFLAGS += -DNO_DEMANGLE
endif
endif
ifndef CC_LD_DYNPATH
ifdef NO_R_TO_GCC_LINKER
# Some gcc does not accept and pass -R to the linker to specify

View file

@ -6,7 +6,16 @@
#include <libelf.h>
#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;