platform_bionic/linker/Android.mk
Nick Kralevich 9ec0f03a0d Add relro support
Add support for PT_GNU_RELRO. This allows the static linker to
indicate that certain regions of memory should be marked as
"read-only" after dynamic linking is complete.

See:
  * http://www.akkadia.org/drepper/nonselsec.pdf (section 6)
  * http://tk-blog.blogspot.com/2009/02/relro-not-so-well-known-memory.html

Note that this change has no effect on Android right now, because
we don't compile our code with relro enabled.

Change-Id: I6541f8775367e8558b4388f7d105b1ae6e8f046b
2012-03-05 16:44:42 -08:00

67 lines
1.8 KiB
Makefile

LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
LOCAL_SRC_FILES:= \
arch/$(TARGET_ARCH)/begin.S \
linker.c \
linker_environ.c \
linker_format.c \
rt.c \
dlfcn.c \
debugger.c
LOCAL_LDFLAGS := -shared
LOCAL_CFLAGS += -fno-stack-protector -Wstrict-overflow=5
# Set LINKER_DEBUG to either 1 or 0
#
LOCAL_CFLAGS += -DLINKER_DEBUG=0
# we need to access the Bionic private header <bionic_tls.h>
# in the linker; duplicate the HAVE_ARM_TLS_REGISTER definition
# from the libc build
ifeq ($(TARGET_ARCH)-$(ARCH_ARM_HAVE_TLS_REGISTER),arm-true)
LOCAL_CFLAGS += -DHAVE_ARM_TLS_REGISTER
endif
LOCAL_CFLAGS += -I$(LOCAL_PATH)/../libc/private
ifeq ($(TARGET_ARCH),arm)
LOCAL_CFLAGS += -DANDROID_ARM_LINKER
else
ifeq ($(TARGET_ARCH),x86)
LOCAL_CFLAGS += -DANDROID_X86_LINKER
endif
endif
LOCAL_MODULE:= linker
LOCAL_STATIC_LIBRARIES := libc_nomalloc
#LOCAL_FORCE_STATIC_EXECUTABLE := true # not necessary when not including BUILD_EXECUTABLE
#
# include $(BUILD_EXECUTABLE)
#
# Instead of including $(BUILD_EXECUTABLE), we execute the steps to create an executable by
# hand, as we want to insert an extra step that is not supported by the build system, and
# is probably specific the linker only, so there's no need to modify the build system for
# the purpose.
LOCAL_MODULE_CLASS := EXECUTABLES
LOCAL_MODULE_SUFFIX := $(TARGET_EXECUTABLE_SUFFIX)
# we don't want crtbegin.o (because we have begin.o), so unset it
# just for this module
LOCAL_NO_CRT := true
include $(BUILD_SYSTEM)/dynamic_binary.mk
$(linked_module): $(TARGET_CRTBEGIN_STATIC_O) $(all_objects) $(all_libraries) $(TARGET_CRTEND_O)
$(transform-o-to-static-executable)
@echo "target PrefixSymbols: $(PRIVATE_MODULE) ($@)"
$(hide) $(TARGET_OBJCOPY) --prefix-symbols=__dl_ $@
#
# end of BUILD_EXECUTABLE hack
#