ifeq ($(src-perf),)
  src-perf := $(srctree)/tools/perf
  endif

  ifeq ($(obj-perf),)
  obj-perf := $(OUTPUT)

  endif

  ifneq ($(obj-perf),)
  obj-perf := $(abspath $(obj-perf))/
  endif

  $(shell printf "" > $(OUTPUT).config-detected)

  detected     = $(shell echo "$(1)=y"       >> $(OUTPUT).config-detected)
  detected_var = $(shell echo "$(1)=$($(1))" >> $(OUTPUT).config-detected)

  CFLAGS := $(EXTRA_CFLAGS) $(EXTRA_WARNINGS)

  include $(srctree)/tools/scripts/Makefile.arch

  $(call detected_var,SRCARCH)

  NO_PERF_REGS := 1

  NO_SYSCALL_TABLE := 1

  # Additional ARCH settings for ppc

  ifeq ($(SRCARCH),powerpc)

    NO_PERF_REGS := 0

    NO_SYSCALL_TABLE := 0
    CFLAGS += -I$(OUTPUT)arch/powerpc/include/generated

    LIBUNWIND_LIBS := -lunwind -lunwind-ppc64

  endif

  # Additional ARCH settings for x86

  ifeq ($(SRCARCH),x86)

    $(call detected,CONFIG_X86)

    ifeq (${IS_64_BIT}, 1)

      NO_SYSCALL_TABLE := 0
      CFLAGS += -DHAVE_ARCH_X86_64_SUPPORT -I$(OUTPUT)arch/x86/include/generated

      ARCH_INCLUDE = ../../arch/x86/lib/memcpy_64.S ../../arch/x86/lib/memset_64.S

      LIBUNWIND_LIBS = -lunwind-x86_64 -lunwind -llzma

      $(call detected,CONFIG_X86_64)

    else

      LIBUNWIND_LIBS = -lunwind-x86 -llzma -lunwind

    endif
    NO_PERF_REGS := 0

  endif

  ifeq ($(SRCARCH),arm)

    NO_PERF_REGS := 0
    LIBUNWIND_LIBS = -lunwind -lunwind-arm
  endif

  ifeq ($(SRCARCH),arm64)

    NO_PERF_REGS := 0

    NO_SYSCALL_TABLE := 0
    CFLAGS += -I$(OUTPUT)arch/arm64/include/generated

    LIBUNWIND_LIBS = -lunwind -lunwind-aarch64
  endif

  ifeq ($(ARCH),s390)
    NO_PERF_REGS := 0

    NO_SYSCALL_TABLE := 0

    CFLAGS += -fPIC -I$(OUTPUT)arch/s390/include/generated

  endif

  ifeq ($(NO_PERF_REGS),0)
    $(call detected,CONFIG_PERF_REGS)
  endif

  ifneq ($(NO_SYSCALL_TABLE),1)

    CFLAGS += -DHAVE_SYSCALL_TABLE_SUPPORT

  endif

  # So far there's only x86 and arm libdw unwind support merged in perf.

  # Disable it on all other architectures in case libdw unwind
  # support is detected in system. Add supported architectures
  # to the check.

  ifneq ($(SRCARCH),$(filter $(SRCARCH),x86 arm arm64 powerpc s390))

    NO_LIBDW_DWARF_UNWIND := 1
  endif

  ifeq ($(LIBUNWIND_LIBS),)
    NO_LIBUNWIND := 1

  endif

  #
  # For linking with debug library, run like:
  #
  #   make DEBUG=1 LIBUNWIND_DIR=/opt/libunwind/
  #

  
  libunwind_arch_set_flags = $(eval $(libunwind_arch_set_flags_code))
  define libunwind_arch_set_flags_code
    FEATURE_CHECK_CFLAGS-libunwind-$(1)  = -I$(LIBUNWIND_DIR)/include
    FEATURE_CHECK_LDFLAGS-libunwind-$(1) = -L$(LIBUNWIND_DIR)/lib
  endef

  ifdef LIBUNWIND_DIR
    LIBUNWIND_CFLAGS  = -I$(LIBUNWIND_DIR)/include
    LIBUNWIND_LDFLAGS = -L$(LIBUNWIND_DIR)/lib

    LIBUNWIND_ARCHS = x86 x86_64 arm aarch64 debug-frame-arm debug-frame-aarch64
    $(foreach libunwind_arch,$(LIBUNWIND_ARCHS),$(call libunwind_arch_set_flags,$(libunwind_arch)))

  endif

  
  # Set per-feature check compilation flags
  FEATURE_CHECK_CFLAGS-libunwind = $(LIBUNWIND_CFLAGS)

  FEATURE_CHECK_LDFLAGS-libunwind = $(LIBUNWIND_LDFLAGS) $(LIBUNWIND_LIBS)

  FEATURE_CHECK_CFLAGS-libunwind-debug-frame = $(LIBUNWIND_CFLAGS)

  FEATURE_CHECK_LDFLAGS-libunwind-debug-frame = $(LIBUNWIND_LDFLAGS) $(LIBUNWIND_LIBS)

  ifdef CSINCLUDES
    LIBOPENCSD_CFLAGS := -I$(CSINCLUDES)
  endif
  OPENCSDLIBS := -lopencsd_c_api -lopencsd
  ifdef CSLIBS
    LIBOPENCSD_LDFLAGS := -L$(CSLIBS)
  endif
  FEATURE_CHECK_CFLAGS-libopencsd := $(LIBOPENCSD_CFLAGS)
  FEATURE_CHECK_LDFLAGS-libopencsd := $(LIBOPENCSD_LDFLAGS) $(OPENCSDLIBS)

  ifeq ($(NO_PERF_REGS),0)

    CFLAGS += -DHAVE_PERF_REGS_SUPPORT

  endif

  # for linking with debug library, run like:
  # make DEBUG=1 LIBDW_DIR=/opt/libdw/
  ifdef LIBDW_DIR
    LIBDW_CFLAGS  := -I$(LIBDW_DIR)/include
    LIBDW_LDFLAGS := -L$(LIBDW_DIR)/lib

  endif

  DWARFLIBS := -ldw
  ifeq ($(findstring -static,${LDFLAGS}),-static)
    DWARFLIBS += -lelf -lebl -ldl -lz -llzma -lbz2
  endif

  FEATURE_CHECK_CFLAGS-libdw-dwarf-unwind := $(LIBDW_CFLAGS)

  FEATURE_CHECK_LDFLAGS-libdw-dwarf-unwind := $(LIBDW_LDFLAGS) $(DWARFLIBS)

  # for linking with debug library, run like:
  # make DEBUG=1 LIBBABELTRACE_DIR=/opt/libbabeltrace/
  ifdef LIBBABELTRACE_DIR
    LIBBABELTRACE_CFLAGS  := -I$(LIBBABELTRACE_DIR)/include
    LIBBABELTRACE_LDFLAGS := -L$(LIBBABELTRACE_DIR)/lib

  endif

  FEATURE_CHECK_CFLAGS-libbabeltrace := $(LIBBABELTRACE_CFLAGS)
  FEATURE_CHECK_LDFLAGS-libbabeltrace := $(LIBBABELTRACE_LDFLAGS) -lbabeltrace-ctf

  FEATURE_CHECK_CFLAGS-bpf = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi -I$(srctree)/tools/include/uapi

  # include ARCH specific config

  -include $(src-perf)/arch/$(SRCARCH)/Makefile

  ifdef PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET
    CFLAGS += -DHAVE_ARCH_REGS_QUERY_REGISTER_OFFSET
  endif

  include $(srctree)/tools/scripts/utilities.mak

  
  ifeq ($(call get-executable,$(FLEX)),)

    dummy := $(error Error: $(FLEX) is missing on this system, please install it)

  endif
  
  ifeq ($(call get-executable,$(BISON)),)

    dummy := $(error Error: $(BISON) is missing on this system, please install it)

  endif

  
  # Treat warnings as errors unless directed not to
  ifneq ($(WERROR),0)

    CFLAGS += -Werror

    CXXFLAGS += -Werror

  endif

  ifndef DEBUG
    DEBUG := 0
  endif

  ifeq ($(DEBUG),0)

  ifeq ($(CC_NO_CLANG), 0)

    CFLAGS += -O3
  else

    CFLAGS += -O6

  endif

  endif

  
  ifdef PARSER_DEBUG

    PARSER_DEBUG_BISON := -t
    PARSER_DEBUG_FLEX  := -d
    CFLAGS             += -DPARSER_DEBUG

    $(call detected_var,PARSER_DEBUG_BISON)
    $(call detected_var,PARSER_DEBUG_FLEX)

  endif

  # Try different combinations to accommodate systems that only have
  # python[2][-config] in weird combinations but always preferring
  # python2 and python2-config as per pep-0394. If we catch a
  # python[-config] in version 3, the version check will kill it.
  PYTHON2 := $(if $(call get-executable,python2),python2,python)
  override PYTHON := $(call get-executable-or-default,PYTHON,$(PYTHON2))
  PYTHON2_CONFIG := \
    $(if $(call get-executable,$(PYTHON)-config),$(PYTHON)-config,python-config)
  override PYTHON_CONFIG := \
    $(call get-executable-or-default,PYTHON_CONFIG,$(PYTHON2_CONFIG))

  grep-libs  = $(filter -l%,$(1))
  strip-libs  = $(filter-out -l%,$(1))

  PYTHON_CONFIG_SQ := $(call shell-sq,$(PYTHON_CONFIG))

  ifdef PYTHON_CONFIG
    PYTHON_EMBED_LDOPTS := $(shell $(PYTHON_CONFIG_SQ) --ldflags 2>/dev/null)
    PYTHON_EMBED_LDFLAGS := $(call strip-libs,$(PYTHON_EMBED_LDOPTS))
    PYTHON_EMBED_LIBADD := $(call grep-libs,$(PYTHON_EMBED_LDOPTS)) -lutil

    PYTHON_EMBED_CCOPTS := $(shell $(PYTHON_CONFIG_SQ) --includes 2>/dev/null)

    FLAGS_PYTHON_EMBED := $(PYTHON_EMBED_CCOPTS) $(PYTHON_EMBED_LDOPTS)

  endif

  FEATURE_CHECK_CFLAGS-libpython := $(PYTHON_EMBED_CCOPTS)
  FEATURE_CHECK_LDFLAGS-libpython := $(PYTHON_EMBED_LDOPTS)
  FEATURE_CHECK_CFLAGS-libpython-version := $(PYTHON_EMBED_CCOPTS)
  FEATURE_CHECK_LDFLAGS-libpython-version := $(PYTHON_EMBED_LDOPTS)

  CFLAGS += -fno-omit-frame-pointer
  CFLAGS += -ggdb3
  CFLAGS += -funwind-tables
  CFLAGS += -Wall
  CFLAGS += -Wextra
  CFLAGS += -std=gnu99

  CXXFLAGS += -std=gnu++11 -fno-exceptions -fno-rtti
  CXXFLAGS += -Wall
  CXXFLAGS += -fno-omit-frame-pointer
  CXXFLAGS += -ggdb3
  CXXFLAGS += -funwind-tables
  CXXFLAGS += -Wno-strict-aliasing

  # Enforce a non-executable stack, as we may regress (again) in the future by
  # adding assembler files missing the .GNU-stack linker note.
  LDFLAGS += -Wl,-z,noexecstack

  EXTLIBS = -lpthread -lrt -lm -ldl

  ifeq ($(FEATURES_DUMP),)

  include $(srctree)/tools/build/Makefile.feature

  else
  include $(FEATURES_DUMP)
  endif

  ifeq ($(feature-stackprotector-all), 1)

    CFLAGS += -fstack-protector-all

  endif

  ifeq ($(DEBUG),0)

    ifeq ($(feature-fortify-source), 1)

      CFLAGS += -D_FORTIFY_SOURCE=2
    endif

  endif

  INC_FLAGS += -I$(src-perf)/util/include

  INC_FLAGS += -I$(src-perf)/arch/$(SRCARCH)/include

  INC_FLAGS += -I$(srctree)/tools/include/uapi
  INC_FLAGS += -I$(srctree)/tools/include/

  INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi
  INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/
  INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/

  
  # $(obj-perf)      for generated common-cmds.h
  # $(obj-perf)/util for generated bison/flex headers
  ifneq ($(OUTPUT),)

  INC_FLAGS += -I$(obj-perf)/util
  INC_FLAGS += -I$(obj-perf)

  endif

  INC_FLAGS += -I$(src-perf)/util
  INC_FLAGS += -I$(src-perf)
  INC_FLAGS += -I$(srctree)/tools/lib/
  
  CFLAGS   += $(INC_FLAGS)
  CXXFLAGS += $(INC_FLAGS)

  CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE

  ifeq ($(feature-sync-compare-and-swap), 1)
    CFLAGS += -DHAVE_SYNC_COMPARE_AND_SWAP_SUPPORT
  endif

  ifeq ($(feature-pthread-attr-setaffinity-np), 1)
    CFLAGS += -DHAVE_PTHREAD_ATTR_SETAFFINITY_NP
  endif

  ifeq ($(feature-pthread-barrier), 1)
    CFLAGS += -DHAVE_PTHREAD_BARRIER
  endif

  ifndef NO_BIONIC

    $(call feature_check,bionic)

    ifeq ($(feature-bionic), 1)
      BIONIC := 1

      CFLAGS += -DLACKS_SIGQUEUE_PROTOTYPE

      CFLAGS += -DLACKS_OPEN_MEMSTREAM_PROTOTYPE

      EXTLIBS := $(filter-out -lrt,$(EXTLIBS))
      EXTLIBS := $(filter-out -lpthread,$(EXTLIBS))
    endif

  endif

  
  ifdef NO_LIBELF

    NO_DWARF := 1
    NO_DEMANGLE := 1
    NO_LIBUNWIND := 1

    NO_LIBDW_DWARF_UNWIND := 1

    NO_LIBBPF := 1

    NO_JVMTI := 1

  else

    ifeq ($(feature-libelf), 0)

      ifeq ($(feature-glibc), 1)

        LIBC_SUPPORT := 1
      endif
      ifeq ($(BIONIC),1)
        LIBC_SUPPORT := 1
      endif
      ifeq ($(LIBC_SUPPORT),1)

        msg := $(warning No libelf found. Disables 'probe' tool, jvmti and BPF support in 'perf record'. Please install libelf-dev, libelf-devel or elfutils-libelf-devel);

  
        NO_LIBELF := 1
        NO_DWARF := 1
        NO_DEMANGLE := 1

        NO_LIBUNWIND := 1
        NO_LIBDW_DWARF_UNWIND := 1

        NO_LIBBPF := 1

        NO_JVMTI := 1

      else

        ifneq ($(filter s% -static%,$(LDFLAGS),),)
          msg := $(error No static glibc found, please install glibc-static);
        else
          msg := $(error No gnu/libc-version.h found, please install glibc-dev[el]);
        endif

      endif

    else

      ifndef NO_LIBDW_DWARF_UNWIND
        ifneq ($(feature-libdw-dwarf-unwind),1)
          NO_LIBDW_DWARF_UNWIND := 1
          msg := $(warning No libdw DWARF unwind found, Please install elfutils-devel/libdw-dev >= 0.158 and/or set LIBDW_DIR);
        endif
      endif

      ifneq ($(feature-dwarf), 1)

        ifndef NO_DWARF
          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

      else
        ifneq ($(feature-dwarf_getlocations), 1)
          msg := $(warning Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157);
        else

          CFLAGS += -DHAVE_DWARF_GETLOCATIONS_SUPPORT

        endif # dwarf_getlocations

      endif # Dwarf support

    endif # libelf support

  endif # NO_LIBELF

  ifeq ($(feature-glibc), 1)
    CFLAGS += -DHAVE_GLIBC_SUPPORT
  endif

  ifdef NO_DWARF
    NO_LIBDW_DWARF_UNWIND := 1
  endif

  ifeq ($(feature-sched_getcpu), 1)
    CFLAGS += -DHAVE_SCHED_GETCPU_SUPPORT
  endif

  ifeq ($(feature-setns), 1)
    CFLAGS += -DHAVE_SETNS_SUPPORT
    $(call detected,CONFIG_SETNS)
  endif

  ifndef NO_CORESIGHT
    ifeq ($(feature-libopencsd), 1)
      CFLAGS += -DHAVE_CSTRACE_SUPPORT $(LIBOPENCSD_CFLAGS)
      LDFLAGS += $(LIBOPENCSD_LDFLAGS)
      EXTLIBS += $(OPENCSDLIBS)
      $(call detected,CONFIG_LIBOPENCSD)
      ifdef CSTRACE_RAW
        CFLAGS += -DCS_DEBUG_RAW
        ifeq (${CSTRACE_RAW}, packed)
          CFLAGS += -DCS_RAW_PACKED
        endif
      endif
    endif
  endif

  ifndef NO_LIBELF

    CFLAGS += -DHAVE_LIBELF_SUPPORT

    EXTLIBS += -lelf

    $(call detected,CONFIG_LIBELF)

    ifeq ($(feature-libelf-mmap), 1)

      CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
    endif

    ifeq ($(feature-libelf-getphdrnum), 1)

      CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
    endif

    ifeq ($(feature-libelf-gelf_getnote), 1)
      CFLAGS += -DHAVE_GELF_GETNOTE_SUPPORT
    else
      msg := $(warning gelf_getnote() not found on libelf, SDT support disabled);
    endif

    ifeq ($(feature-libelf-getshdrstrndx), 1)
      CFLAGS += -DHAVE_ELF_GETSHDRSTRNDX_SUPPORT
    endif

    ifndef NO_DWARF
      ifeq ($(origin PERF_HAVE_DWARF_REGS), undefined)

        msg := $(warning DWARF register mappings have not been defined for architecture $(SRCARCH), DWARF support disabled);

        NO_DWARF := 1
      else
        CFLAGS += -DHAVE_DWARF_SUPPORT $(LIBDW_CFLAGS)
        LDFLAGS += $(LIBDW_LDFLAGS)

        EXTLIBS += ${DWARFLIBS}

        $(call detected,CONFIG_DWARF)

      endif # PERF_HAVE_DWARF_REGS
    endif # NO_DWARF

  
    ifndef NO_LIBBPF
      ifeq ($(feature-bpf), 1)
        CFLAGS += -DHAVE_LIBBPF_SUPPORT
        $(call detected,CONFIG_LIBBPF)
      endif

  
      ifndef NO_DWARF
        ifdef PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET
          CFLAGS += -DHAVE_BPF_PROLOGUE
          $(call detected,CONFIG_BPF_PROLOGUE)
        else

          msg := $(warning BPF prologue is not supported by architecture $(SRCARCH), missing regs_query_register_offset());

        endif
      else
        msg := $(warning DWARF support is off, BPF prologue is disabled);
      endif

    endif # NO_LIBBPF

  endif # NO_LIBELF

  ifndef NO_SDT
    ifneq ($(feature-sdt), 1)
      msg := $(warning No sys/sdt.h found, no SDT events are defined, please install systemtap-sdt-devel or systemtap-sdt-dev);
      NO_SDT := 1;
    else
      CFLAGS += -DHAVE_SDT_EVENT
      $(call detected,CONFIG_SDT_EVENT)
    endif
  endif

  ifdef PERF_HAVE_JITDUMP

    ifndef NO_LIBELF

      $(call detected,CONFIG_JITDUMP)
      CFLAGS += -DHAVE_JITDUMP
    endif
  endif

  ifeq ($(SRCARCH),powerpc)

    ifndef NO_DWARF
      CFLAGS += -DHAVE_SKIP_CALLCHAIN_IDX
    endif
  endif

  ifndef NO_LIBUNWIND

    have_libunwind :=

  
    ifeq ($(feature-libunwind-x86), 1)
      $(call detected,CONFIG_LIBUNWIND_X86)
      CFLAGS += -DHAVE_LIBUNWIND_X86_SUPPORT
      LDFLAGS += -lunwind-x86

      EXTLIBS_LIBUNWIND += -lunwind-x86

      have_libunwind = 1
    endif

    ifeq ($(feature-libunwind-aarch64), 1)
      $(call detected,CONFIG_LIBUNWIND_AARCH64)
      CFLAGS += -DHAVE_LIBUNWIND_AARCH64_SUPPORT
      LDFLAGS += -lunwind-aarch64

      EXTLIBS_LIBUNWIND += -lunwind-aarch64

      have_libunwind = 1
      $(call feature_check,libunwind-debug-frame-aarch64)
      ifneq ($(feature-libunwind-debug-frame-aarch64), 1)
        msg := $(warning No debug_frame support found in libunwind-aarch64);
        CFLAGS += -DNO_LIBUNWIND_DEBUG_FRAME_AARCH64
      endif
    endif

    ifneq ($(feature-libunwind), 1)

      msg := $(warning No libunwind found. Please install libunwind-dev[el] >= 1.1 and/or set LIBUNWIND_DIR);

      NO_LOCAL_LIBUNWIND := 1
    else
      have_libunwind := 1
      $(call detected,CONFIG_LOCAL_LIBUNWIND)
    endif
  
    ifneq ($(have_libunwind), 1)

      NO_LIBUNWIND := 1

    endif

  else
    NO_LOCAL_LIBUNWIND := 1

  endif

  ifndef NO_LIBBPF
    ifneq ($(feature-bpf), 1)
      msg := $(warning BPF API too old. Please install recent kernel headers. BPF support in 'perf record' is disabled.)
      NO_LIBBPF := 1
    endif
  endif

  dwarf-post-unwind := 1
  dwarf-post-unwind-text := BUG
  
  # setup DWARF post unwinder
  ifdef NO_LIBUNWIND
    ifdef NO_LIBDW_DWARF_UNWIND
      msg := $(warning Disabling post unwind, no support found.);
      dwarf-post-unwind := 0

    else

      dwarf-post-unwind-text := libdw

      $(call detected,CONFIG_LIBDW_DWARF_UNWIND)

    endif
  else
    dwarf-post-unwind-text := libunwind

    $(call detected,CONFIG_LIBUNWIND)

    # Enable libunwind support by default.
    ifndef NO_LIBDW_DWARF_UNWIND
      NO_LIBDW_DWARF_UNWIND := 1
    endif
  endif
  
  ifeq ($(dwarf-post-unwind),1)
    CFLAGS += -DHAVE_DWARF_UNWIND_SUPPORT

    $(call detected,CONFIG_DWARF_UNWIND)

  else
    NO_DWARF_UNWIND := 1
  endif

  ifndef NO_LOCAL_LIBUNWIND

    ifeq ($(SRCARCH),$(filter $(SRCARCH),arm arm64))

      $(call feature_check,libunwind-debug-frame)
      ifneq ($(feature-libunwind-debug-frame), 1)
        msg := $(warning No debug_frame support found in libunwind);

        CFLAGS += -DNO_LIBUNWIND_DEBUG_FRAME
      endif

    else
      # non-ARM has no dwarf_find_debug_frame() function:
      CFLAGS += -DNO_LIBUNWIND_DEBUG_FRAME
    endif

    EXTLIBS += $(LIBUNWIND_LIBS)

    LDFLAGS += $(LIBUNWIND_LIBS)
  endif

  ifeq ($(findstring -static,${LDFLAGS}),-static)
    # gcc -static links libgcc_eh which contans piece of libunwind
    LIBUNWIND_LDFLAGS += -Wl,--allow-multiple-definition
  endif

  
  ifndef NO_LIBUNWIND
    CFLAGS  += -DHAVE_LIBUNWIND_SUPPORT

    CFLAGS  += $(LIBUNWIND_CFLAGS)
    LDFLAGS += $(LIBUNWIND_LDFLAGS)

    EXTLIBS += $(EXTLIBS_LIBUNWIND)

  endif

  ifeq ($(NO_SYSCALL_TABLE),0)
    $(call detected,CONFIG_TRACE)
  else
    ifndef NO_LIBAUDIT
      ifneq ($(feature-libaudit), 1)
        msg := $(warning No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev);
        NO_LIBAUDIT := 1
      else
        CFLAGS += -DHAVE_LIBAUDIT_SUPPORT
        EXTLIBS += -laudit
        $(call detected,CONFIG_TRACE)
      endif

    endif

  endif

  ifndef NO_LIBCRYPTO
    ifneq ($(feature-libcrypto), 1)
      msg := $(warning No libcrypto.h found, disables jitted code injection, please install libssl-devel or libssl-dev);
      NO_LIBCRYPTO := 1
    else
      CFLAGS += -DHAVE_LIBCRYPTO_SUPPORT
      EXTLIBS += -lcrypto
      $(call detected,CONFIG_CRYPTO)
    endif
  endif

  ifdef NO_NEWT

    NO_SLANG=1

  endif
  
  ifndef NO_SLANG

    ifneq ($(feature-libslang), 1)

      msg := $(warning slang not found, disables TUI support. Please install slang-devel, libslang-dev or libslang2-dev);

      NO_SLANG := 1
    else
      # Fedora has /usr/include/slang/slang.h, but ubuntu /usr/include/slang.h
      CFLAGS += -I/usr/include/slang

      CFLAGS += -DHAVE_SLANG_SUPPORT

      EXTLIBS += -lslang

      $(call detected,CONFIG_SLANG)

    endif

  endif

  
  ifndef NO_GTK2

    FLAGS_GTK2=$(CFLAGS) $(LDFLAGS) $(EXTLIBS) $(shell $(PKG_CONFIG) --libs --cflags gtk+-2.0 2>/dev/null)

    ifneq ($(feature-gtk2), 1)

      msg := $(warning GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev);
      NO_GTK2 := 1
    else

      ifeq ($(feature-gtk2-infobar), 1)

        GTK_CFLAGS := -DHAVE_GTK_INFO_BAR_SUPPORT

      endif

      CFLAGS += -DHAVE_GTK2_SUPPORT

      GTK_CFLAGS += $(shell $(PKG_CONFIG) --cflags gtk+-2.0 2>/dev/null)
      GTK_LIBS := $(shell $(PKG_CONFIG) --libs gtk+-2.0 2>/dev/null)

      EXTLIBS += -ldl

    endif

  endif

  ifdef NO_LIBPERL

    CFLAGS += -DNO_LIBPERL

  else

    PERL_EMBED_LDOPTS = $(shell perl -MExtUtils::Embed -e ldopts 2>/dev/null)
    PERL_EMBED_LDFLAGS = $(call strip-libs,$(PERL_EMBED_LDOPTS))
    PERL_EMBED_LIBADD = $(call grep-libs,$(PERL_EMBED_LDOPTS))

    PERL_EMBED_CCOPTS = $(shell perl -MExtUtils::Embed -e ccopts 2>/dev/null)

    PERL_EMBED_CCOPTS := $(filter-out -specs=%,$(PERL_EMBED_CCOPTS))
    PERL_EMBED_LDOPTS := $(filter-out -specs=%,$(PERL_EMBED_LDOPTS))

    FLAGS_PERL_EMBED=$(PERL_EMBED_CCOPTS) $(PERL_EMBED_LDOPTS)

    ifneq ($(feature-libperl), 1)

      CFLAGS += -DNO_LIBPERL
      NO_LIBPERL := 1

      msg := $(warning Missing perl devel files. Disabling perl scripting support, please install perl-ExtUtils-Embed/libperl-dev);

    else
      LDFLAGS += $(PERL_EMBED_LDFLAGS)
      EXTLIBS += $(PERL_EMBED_LIBADD)

      CFLAGS += -DHAVE_LIBPERL_SUPPORT

      $(call detected,CONFIG_LIBPERL)

    endif

  endif

  ifeq ($(feature-timerfd), 1)
    CFLAGS += -DHAVE_TIMERFD_SUPPORT
  else
    msg := $(warning No timerfd support. Disables 'perf kvm stat live');
  endif

  disable-python = $(eval $(disable-python_code))
  define disable-python_code

    CFLAGS += -DNO_LIBPYTHON

    $(warning $1)

    NO_LIBPYTHON := 1
  endef

  ifdef NO_LIBPYTHON

    $(call disable-python,Python support disabled by user)

  else

    ifndef PYTHON

      $(call disable-python,No python interpreter was found: disables Python support - please install python-devel/python-dev)

    else

      PYTHON_WORD := $(call shell-wordify,$(PYTHON))

  
      ifndef PYTHON_CONFIG

        $(call disable-python,No 'python-config' tool was found: disables Python support - please install python-devel/python-dev)

      else

        ifneq ($(feature-libpython), 1)

          $(call disable-python,No 'Python.h' (for Python 2.x support) was found: disables Python support - please install python-devel/python-dev)

        else

           LDFLAGS += $(PYTHON_EMBED_LDFLAGS)
           EXTLIBS += $(PYTHON_EMBED_LIBADD)
           LANG_BINDINGS += $(obj-perf)python/perf.so

           CFLAGS += -DHAVE_LIBPYTHON_SUPPORT

           $(call detected,CONFIG_LIBPYTHON)

        endif
      endif
    endif
  endif

  ifeq ($(feature-libbfd), 1)

    EXTLIBS += -lbfd

  else
    # we are on a system that requires -liberty and (maybe) -lz
    # to link against -lbfd; test each case individually here

  
    # call all detections now so we get correct
    # status in VF output

    $(call feature_check,libbfd-liberty)
    $(call feature_check,libbfd-liberty-z)

    ifeq ($(feature-libbfd-liberty), 1)
      EXTLIBS += -lbfd -liberty

    else

      ifeq ($(feature-libbfd-liberty-z), 1)
        EXTLIBS += -lbfd -liberty -lz

      endif
    endif

  endif

  ifdef NO_DEMANGLE

    CFLAGS += -DNO_DEMANGLE

  else

    ifdef HAVE_CPLUS_DEMANGLE_SUPPORT

      EXTLIBS += -liberty

    else

      ifeq ($(filter -liberty,$(EXTLIBS)),)
        $(call feature_check,cplus-demangle)
  
        # we dont have neither HAVE_CPLUS_DEMANGLE_SUPPORT
        # or any of 'bfd iberty z' trinity
        ifeq ($(feature-cplus-demangle), 1)
          EXTLIBS += -liberty
        else
          msg := $(warning No bfd.h/libbfd found, please install binutils-dev[el]/zlib-static/libiberty-dev to gain symbol demangling)
          CFLAGS += -DNO_DEMANGLE

        endif
      endif
    endif

  
    ifneq ($(filter -liberty,$(EXTLIBS)),)
      CFLAGS += -DHAVE_CPLUS_DEMANGLE_SUPPORT
    endif

  endif

  ifneq ($(filter -lbfd,$(EXTLIBS)),)
    CFLAGS += -DHAVE_LIBBFD_SUPPORT
  endif

  ifndef NO_ZLIB
    ifeq ($(feature-zlib), 1)
      CFLAGS += -DHAVE_ZLIB_SUPPORT
      EXTLIBS += -lz

      $(call detected,CONFIG_ZLIB)

    else
      NO_ZLIB := 1
    endif
  endif

  ifndef NO_LZMA
    ifeq ($(feature-lzma), 1)
      CFLAGS += -DHAVE_LZMA_SUPPORT
      EXTLIBS += -llzma
      $(call detected,CONFIG_LZMA)
    else
      msg := $(warning No liblzma found, disables xz kernel module decompression, please install xz-devel/liblzma-dev);
      NO_LZMA := 1
    endif
  endif

  ifndef NO_BACKTRACE

    ifeq ($(feature-backtrace), 1)

      CFLAGS += -DHAVE_BACKTRACE_SUPPORT

    endif

  endif

  
  ifndef NO_LIBNUMA

    ifeq ($(feature-libnuma), 0)

      msg := $(warning No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev);

      NO_LIBNUMA := 1
    else

      ifeq ($(feature-numa_num_possible_cpus), 0)
        msg := $(warning Old numa library found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev >= 2.0.8);
        NO_LIBNUMA := 1
      else
        CFLAGS += -DHAVE_LIBNUMA_SUPPORT
        EXTLIBS += -lnuma
        $(call detected,CONFIG_NUMA)
      endif

    endif

  endif

  ifdef HAVE_KVM_STAT_SUPPORT
      CFLAGS += -DHAVE_KVM_STAT_SUPPORT
  endif

  ifeq (${IS_64_BIT}, 1)
    ifndef NO_PERF_READ_VDSO32
      $(call feature_check,compile-32)

      ifeq ($(feature-compile-32), 1)
        CFLAGS += -DHAVE_PERF_READ_VDSO32
      else

        NO_PERF_READ_VDSO32 := 1
      endif
    endif

    ifneq ($(SRCARCH), x86)

      NO_PERF_READ_VDSOX32 := 1
    endif
    ifndef NO_PERF_READ_VDSOX32
      $(call feature_check,compile-x32)

      ifeq ($(feature-compile-x32), 1)
        CFLAGS += -DHAVE_PERF_READ_VDSOX32
      else

        NO_PERF_READ_VDSOX32 := 1
      endif
    endif
  else
    NO_PERF_READ_VDSO32 := 1
    NO_PERF_READ_VDSOX32 := 1
  endif

  ifndef NO_LIBBABELTRACE

    $(call feature_check,libbabeltrace)
    ifeq ($(feature-libbabeltrace), 1)

      CFLAGS += -DHAVE_LIBBABELTRACE_SUPPORT $(LIBBABELTRACE_CFLAGS)
      LDFLAGS += $(LIBBABELTRACE_LDFLAGS)
      EXTLIBS += -lbabeltrace-ctf

      $(call detected,CONFIG_LIBBABELTRACE)

    else
      msg := $(warning No libbabeltrace found, disables 'perf data' CTF format support, please install libbabeltrace-dev[el]/libbabeltrace-ctf-dev);

    endif
  endif

  ifndef NO_AUXTRACE

    ifeq ($(SRCARCH),x86)

      ifeq ($(feature-get_cpuid), 0)
        msg := $(warning Your gcc lacks the __get_cpuid() builtin, disables support for auxtrace/Intel PT, please install a newer gcc);
        NO_AUXTRACE := 1
      endif
    endif
    ifndef NO_AUXTRACE

      $(call detected,CONFIG_AUXTRACE)
      CFLAGS += -DHAVE_AUXTRACE_SUPPORT
    endif

  endif

  ifndef NO_JVMTI
    ifneq (,$(wildcard /usr/sbin/update-java-alternatives))
      JDIR=$(shell /usr/sbin/update-java-alternatives -l | head -1 | awk '{print $$3}')
    else
      ifneq (,$(wildcard /usr/sbin/alternatives))

        JDIR=$(shell /usr/sbin/alternatives --display java | tail -1 | cut -d' ' -f 5 | sed 's%/jre/bin/java.%%g')

      endif
    endif
    ifndef JDIR
      $(warning No alternatives command found, you need to set JDIR= to point to the root of your Java directory)
      NO_JVMTI := 1
    endif
  endif
  
  ifndef NO_JVMTI
    FEATURE_CHECK_CFLAGS-jvmti := -I$(JDIR)/include -I$(JDIR)/include/linux
    $(call feature_check,jvmti)
    ifeq ($(feature-jvmti), 1)
      $(call detected_var,JDIR)
    else

      $(warning No openjdk development package found, please install JDK package, e.g. openjdk-8-jdk, java-1.8.0-openjdk-devel)

      NO_JVMTI := 1
    endif
  endif

  USE_CXX = 0
  USE_CLANGLLVM = 0
  ifdef LIBCLANGLLVM
    $(call feature_check,cxx)
    ifneq ($(feature-cxx), 1)
      msg := $(warning No g++ found, disable clang and llvm support. Please install g++)
    else
      $(call feature_check,llvm)

      $(call feature_check,llvm-version)

      ifneq ($(feature-llvm), 1)

        msg := $(warning No suitable libLLVM found, disabling builtin clang and LLVM support. Please install llvm-dev(el) (>= 3.9.0))

      else
        $(call feature_check,clang)
        ifneq ($(feature-clang), 1)

          msg := $(warning No suitable libclang found, disabling builtin clang and LLVM support. Please install libclang-dev(el) (>= 3.9.0))

        else
          CFLAGS += -DHAVE_LIBCLANGLLVM_SUPPORT
          CXXFLAGS += -DHAVE_LIBCLANGLLVM_SUPPORT -I$(shell $(LLVM_CONFIG) --includedir)
          $(call detected,CONFIG_CXX)
          $(call detected,CONFIG_CLANGLLVM)
  	USE_CXX = 1
  	USE_LLVM = 1
  	USE_CLANG = 1

          ifneq ($(feature-llvm-version),1)
            msg := $(warning This version of LLVM is not tested. May cause build errors)
          endif

        endif
      endif
    endif
  endif

  # Among the variables below, these:
  #   perfexecdir

  #   perf_include_dir

  #   perf_examples_dir

  #   template_dir
  #   mandir
  #   infodir
  #   htmldir
  #   ETC_PERFCONFIG (but not sysconfdir)
  # can be specified as a relative path some/where/else;
  # this is interpreted as relative to $(prefix) and "perf" at
  # runtime figures out where they are based on the path to the executable.
  # This can help installing the suite in a relocatable way.
  
  # Make the path relative to DESTDIR, not to prefix
  ifndef DESTDIR

  prefix ?= $(HOME)

  endif
  bindir_relative = bin

  bindir = $(abspath $(prefix)/$(bindir_relative))

  mandir = share/man
  infodir = share/info
  perfexecdir = libexec/perf-core

  perf_include_dir = lib/perf/include
  perf_examples_dir = lib/perf/examples

  sharedir = $(prefix)/share
  template_dir = share/perf-core/templates

  STRACE_GROUPS_DIR = share/perf-core/strace/groups

  htmldir = share/doc/perf-doc

  tipdir = share/doc/perf-tip

  srcdir = $(srctree)/tools/perf

  ifeq ($(prefix),/usr)
  sysconfdir = /etc
  ETC_PERFCONFIG = $(sysconfdir)/perfconfig
  else
  sysconfdir = $(prefix)/etc
  ETC_PERFCONFIG = etc/perfconfig
  endif

  ifndef lib

  ifeq ($(SRCARCH)$(IS_64_BIT), x861)

  lib = lib64
  else

  lib = lib

  endif

  endif # lib

  libdir = $(prefix)/$(lib)

  
  # Shell quote (do not use $(call) to accommodate ancient setups);
  ETC_PERFCONFIG_SQ = $(subst ','\'',$(ETC_PERFCONFIG))

  STRACE_GROUPS_DIR_SQ = $(subst ','\'',$(STRACE_GROUPS_DIR))

  DESTDIR_SQ = $(subst ','\'',$(DESTDIR))
  bindir_SQ = $(subst ','\'',$(bindir))
  mandir_SQ = $(subst ','\'',$(mandir))
  infodir_SQ = $(subst ','\'',$(infodir))
  perfexecdir_SQ = $(subst ','\'',$(perfexecdir))

  perf_include_dir_SQ = $(subst ','\'',$(perf_include_dir))

  perf_examples_dir_SQ = $(subst ','\'',$(perf_examples_dir))

  template_dir_SQ = $(subst ','\'',$(template_dir))
  htmldir_SQ = $(subst ','\'',$(htmldir))

  tipdir_SQ = $(subst ','\'',$(tipdir))

  prefix_SQ = $(subst ','\'',$(prefix))
  sysconfdir_SQ = $(subst ','\'',$(sysconfdir))

  libdir_SQ = $(subst ','\'',$(libdir))

  srcdir_SQ = $(subst ','\'',$(srcdir))

  
  ifneq ($(filter /%,$(firstword $(perfexecdir))),)
  perfexec_instdir = $(perfexecdir)

  perf_include_instdir = $(perf_include_dir)

  perf_examples_instdir = $(perf_examples_dir)

  STRACE_GROUPS_INSTDIR = $(STRACE_GROUPS_DIR)

  tip_instdir = $(tipdir)

  else
  perfexec_instdir = $(prefix)/$(perfexecdir)

  perf_include_instdir = $(prefix)/$(perf_include_dir)

  perf_examples_instdir = $(prefix)/$(perf_examples_dir)

  STRACE_GROUPS_INSTDIR = $(prefix)/$(STRACE_GROUPS_DIR)

  tip_instdir = $(prefix)/$(tipdir)

  endif
  perfexec_instdir_SQ = $(subst ','\'',$(perfexec_instdir))

  perf_include_instdir_SQ = $(subst ','\'',$(perf_include_instdir))

  perf_examples_instdir_SQ = $(subst ','\'',$(perf_examples_instdir))

  STRACE_GROUPS_INSTDIR_SQ = $(subst ','\'',$(STRACE_GROUPS_INSTDIR))

  tip_instdir_SQ = $(subst ','\'',$(tip_instdir))

  
  # If we install to $(HOME) we keep the traceevent default:
  # $(HOME)/.traceevent/plugins
  # Otherwise we install plugins into the global $(libdir).
  ifdef DESTDIR
  plugindir=$(libdir)/traceevent/plugins

  plugindir_SQ= $(subst ','\'',$(plugindir))

  endif

  print_var = $(eval $(print_var_code)) $(info $(MSG))
  define print_var_code

      MSG = $(shell printf '...%30s: %s' $(1) $($(1)))
  endef

  ifeq ($(VF),1)

    # Display EXTRA features which are detected manualy
    # from here with feature_check call and thus cannot
    # be partof global state output.
    $(foreach feat,$(FEATURE_TESTS_EXTRA),$(call feature_print_status,$(feat),))

    $(call print_var,prefix)
    $(call print_var,bindir)
    $(call print_var,libdir)
    $(call print_var,sysconfdir)
    $(call print_var,LIBUNWIND_DIR)
    $(call print_var,LIBDW_DIR)

    $(call print_var,JDIR)

  
    ifeq ($(dwarf-post-unwind),1)
      $(call feature_print_text,"DWARF post unwind library", $(dwarf-post-unwind-text))
    endif

    $(info )
  endif

  
  $(call detected_var,bindir_SQ)
  $(call detected_var,PYTHON_WORD)
  ifneq ($(OUTPUT),)
  $(call detected_var,OUTPUT)
  endif

  $(call detected_var,htmldir_SQ)
  $(call detected_var,infodir_SQ)
  $(call detected_var,mandir_SQ)

  $(call detected_var,ETC_PERFCONFIG_SQ)

  $(call detected_var,STRACE_GROUPS_DIR_SQ)

  $(call detected_var,prefix_SQ)
  $(call detected_var,perfexecdir_SQ)

  $(call detected_var,perf_include_dir_SQ)

  $(call detected_var,perf_examples_dir_SQ)

  $(call detected_var,tipdir_SQ)

  $(call detected_var,srcdir_SQ)

  $(call detected_var,LIBDIR)

  $(call detected_var,GTK_CFLAGS)

  $(call detected_var,PERL_EMBED_CCOPTS)
  $(call detected_var,PYTHON_EMBED_CCOPTS)