libc: Cleanup the libc makefile.

Removes a lot of redundant code, and reorganizes the file. We first
setup all the comomn variables we may need, and then define the
actual libraries that need to be generated.

Signed-off-by: Dima Zavin <dima@android.com>

1 files changed, 84 insertions, 116 deletions

diff --git a/libc/Android.mk b/libc/Android.mk
index 333dd1e..1c1b312 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -1,6 +1,9 @@
 LOCAL_PATH:= $(call my-dir)
 
 include $(LOCAL_PATH)/arch-$(TARGET_ARCH)/syscalls.mk
+
+# Define the common source files for all the libc instances
+# =========================================================
 libc_common_src_files := \
 	$(syscall_src) \
 	unistd/abort.c \
@@ -272,6 +275,8 @@ libc_common_src_files := \
 	netbsd/nameser/ns_print.c \
 	netbsd/nameser/ns_samedomain.c
 
+# Architecture specific source files go here
+# =========================================================
 ifeq ($(TARGET_ARCH),arm)
 libc_common_src_files += \
 	bionic/eabi.c \
@@ -301,6 +306,14 @@ libc_common_src_files += \
 	bionic/pthread.c.arm \
 	bionic/pthread-timers.c.arm \
 	bionic/ptrace.c.arm
+
+# these are used by the static and dynamic versions of the libc
+# respectively
+libc_arch_static_src_files := \
+	arch-arm/bionic/exidx_static.c
+
+libc_arch_dynamic_src_files := \
+	arch-arm/bionic/exidx_dynamic.c
 else # !arm
 
 ifeq ($(TARGET_ARCH),x86)
@@ -322,10 +335,17 @@ libc_common_src_files += \
 	bionic/pthread.c \
 	bionic/pthread-timers.c \
 	bionic/ptrace.c
-endif # x86
 
+# this is needed for static versions of libc
+libc_arch_static_src_files := \
+	arch-x86/bionic/dl_iterate_phdr_static.c
+
+libc_arch_dynamic_src_files :=
+endif # x86
 endif # !arm
 
+# Define some common cflags
+# ========================================================
 libc_common_cflags := \
 		-DWITH_ERRLIST			\
 		-DANDROID_CHANGES		\
@@ -337,6 +357,7 @@ libc_common_cflags := \
 		-DNEED_PSELECT=1		\
 		-DINET6 \
 		-I$(LOCAL_PATH)/private \
+		-DUSE_DL_PREFIX
 
 ifeq ($(strip $(DEBUG_BIONIC_LIBC)),true)
   libc_common_cflags += -DDEBUG
@@ -344,155 +365,124 @@ endif
 
 ifeq ($(TARGET_ARCH),arm)
   libc_common_cflags += -fstrict-aliasing
-endif
+  libc_crt_target_cflags := -mthumb-interwork
+else # !arm
+  ifeq ($(TARGET_ARCH),x86)
+    libc_crt_target_cflags := -m32
+  endif # x86
+endif # !arm
 
+# Define some common includes
+# ========================================================
 libc_common_c_includes := \
 		$(LOCAL_PATH)/stdlib  \
 		$(LOCAL_PATH)/string  \
 		$(LOCAL_PATH)/stdio
 
-# libc_common.a
-# ========================================================
 
-include $(CLEAR_VARS)
+# Define the libc run-time (crt) support object files that must be built,
+# which are needed to build all other objects (shared/static libs and
+# executables)
+# ==========================================================================
 
-LOCAL_SRC_FILES := $(libc_common_src_files)
-LOCAL_CFLAGS := $(libc_common_cflags) -DUSE_DL_PREFIX
-LOCAL_C_INCLUDES := $(libc_common_c_includes)
-
-ifneq ($(TARGET_SIMULATOR),true)
-  ifeq ($(TARGET_ARCH),arm)
-    crtend_target_cflags := -mthumb-interwork
-  else
-    ifeq ($(TARGET_ARCH),x86)
-      crtend_target_cflags := -m32
-    endif
-  endif
-# We rename crtend.o to crtend_android.o to avoid a
-# name clash between gcc and bionic.
-GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtend_android.o
-$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtend.S
+ifeq ($(TARGET_ARCH),x86)
+# we only need begin_so/end_so for x86, since it needs an appropriate .init
+# section in the shared library with a function to call all the entries in
+# .ctors section. ARM uses init_array, and does not need the function.
+GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_so.o
+$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtbegin_so.S
 	@mkdir -p $(dir $@)
-	$(TARGET_CC) $(crtend_target_cflags) -o $@ -c $<
+	$(TARGET_CC) $(libc_crt_target_cflags) -o $@ -c $<
 ALL_GENERATED_SOURCES += $(GEN)
-endif
-
 
-# crtbegin_so.o/crtend_so.o
-# These are needed for building the shared libs.
-ifneq ($(TARGET_SIMULATOR),true)
+GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtend_so.o
+$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtend_so.S
+	@mkdir -p $(dir $@)
+	$(TARGET_CC) $(libc_crt_target_cflags) -o $@ -c $<
+ALL_GENERATED_SOURCES += $(GEN)
+endif # TARGET_ARCH == x86
 
-ifeq ($(TARGET_ARCH),x86)
 
-crt_begin_end_so_target_cflags := -m32
+GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_static.o
+$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtbegin_static.S
+	@mkdir -p $(dir $@)
+	$(TARGET_CC) $(libc_crt_target_cflags) -o $@ -c $<
+ALL_GENERATED_SOURCES += $(GEN)
 
-GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_so.o
-$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtbegin_so.S
+GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_dynamic.o
+$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtbegin_dynamic.S
 	@mkdir -p $(dir $@)
-	$(TARGET_CC) $(crt_begin_end_so_target_cflags) -o $@ -c $<
+	$(TARGET_CC) $(libc_crt_target_cflags) -o $@ -c $<
 ALL_GENERATED_SOURCES += $(GEN)
 
-GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtend_so.o
-$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtend_so.S
+
+# We rename crtend.o to crtend_android.o to avoid a
+# name clash between gcc and bionic.
+GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtend_android.o
+$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtend.S
 	@mkdir -p $(dir $@)
-	$(TARGET_CC) $(crt_begin_end_so_target_cflags) -o $@ -c $<
+	$(TARGET_CC) $(libc_crt_target_cflags) -o $@ -c $<
 ALL_GENERATED_SOURCES += $(GEN)
 
-endif # TARGET_ARCH == x86
 
-endif # !TARGET_SIMULATOR
+# To enable malloc leak check for statically linked programs, add
+# "WITH_MALLOC_CHECK_LIBC_A := true" to buildspec.mk
+WITH_MALLOC_CHECK_LIBC_A := $(strip $(WITH_MALLOC_CHECK_LIBC_A))
 
+# ========================================================
+# libc_common.a
+# ========================================================
+include $(CLEAR_VARS)
 
+LOCAL_SRC_FILES := $(libc_common_src_files)
+LOCAL_CFLAGS := $(libc_common_cflags)
+LOCAL_C_INCLUDES := $(libc_common_c_includes)
 LOCAL_MODULE := libc_common
 LOCAL_SYSTEM_SHARED_LIBRARIES :=
 
 include $(BUILD_STATIC_LIBRARY)
 
 
+# ========================================================
 # libc.a
 # ========================================================
-
 include $(CLEAR_VARS)
 
-include $(LOCAL_PATH)/arch-$(TARGET_ARCH)/syscalls.mk
-
-# To enable malloc leak check for statically linked programs, add
-# "WITH_MALLOC_CHECK_LIBC_A := true" to device/buildspec.mk
-WITH_MALLOC_CHECK_LIBC_A := $(strip $(WITH_MALLOC_CHECK_LIBC_A))
-
 LOCAL_SRC_FILES := \
-	$(libc_common_src_files) \
+	$(libc_arch_static_src_files) \
 	bionic/dlmalloc.c \
 	bionic/libc_init_static.c
 
+LOCAL_CFLAGS := $(libc_common_cflags)
+
 ifeq ($(WITH_MALLOC_CHECK_LIBC_A),true)
+  LOCAL_CFLAGS += -DMALLOC_LEAK_CHECK
   LOCAL_SRC_FILES += bionic/malloc_leak.c.arm
 endif
 
-ifeq ($(TARGET_ARCH),arm)
-LOCAL_SRC_FILES += \
-	arch-arm/bionic/exidx_static.c
-
-else # TARGET_ARCH != arm
-
-ifeq ($(TARGET_ARCH),x86)
-LOCAL_SRC_FILES += \
-	arch-x86/bionic/dl_iterate_phdr_static.c
-endif
-
-endif
-
-ifneq ($(TARGET_SIMULATOR),true)
-  ifeq ($(TARGET_ARCH),arm)
-    crtbegin_static_target_cflags := -mthumb-interwork
-  else
-    ifeq ($(TARGET_ARCH),x86)
-      crtbegin_static_target_cflags := -m32
-    endif
-  endif
-GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_static.o
-$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtbegin_static.S
-	@mkdir -p $(dir $@)
-	$(TARGET_CC) $(crtbegin_static_target_cflags) -o $@ -c $<
-ALL_GENERATED_SOURCES += $(GEN)
-endif
-
-LOCAL_CFLAGS := $(libc_common_cflags)
-
 LOCAL_C_INCLUDES := $(libc_common_c_includes)
 
-ifeq ($(WITH_MALLOC_CHECK_LIBC_A),true)
-  LOCAL_CFLAGS += -DUSE_DL_PREFIX -DMALLOC_LEAK_CHECK
-endif
-
+LOCAL_MODULE := libc
 LOCAL_WHOLE_STATIC_LIBRARIES := libc_common
-LOCAL_MODULE:= libc
 LOCAL_SYSTEM_SHARED_LIBRARIES :=
 
 include $(BUILD_STATIC_LIBRARY)
 
 
+# ========================================================
 # libc.so
 # ========================================================
-
 include $(CLEAR_VARS)
 
 LOCAL_CFLAGS := $(libc_common_cflags)
-
-LOCAL_CFLAGS += -DUSE_DL_PREFIX
-
 LOCAL_C_INCLUDES := $(libc_common_c_includes)
 
 LOCAL_SRC_FILES := \
+	$(libc_arch_dynamic_src_files) \
 	bionic/dlmalloc.c \
 	bionic/malloc_leak.c.arm \
 	bionic/libc_init_dynamic.c
 
-ifeq ($(TARGET_ARCH),arm)
-LOCAL_SRC_FILES += \
-	arch-arm/bionic/exidx_dynamic.c
-endif
-
 LOCAL_MODULE:= libc
 
 # WARNING: The only library libc.so should depend on is libdl.so!  If you add other libraries,
@@ -507,45 +497,26 @@ LOCAL_SHARED_LIBRARIES := libdl
 LOCAL_WHOLE_STATIC_LIBRARIES := libc_common
 LOCAL_SYSTEM_SHARED_LIBRARIES :=
 
-ifneq ($(TARGET_SIMULATOR),true)
-  ifeq ($(TARGET_ARCH),arm)
-    crtbegin_dynamic_target_cflags := -mthumb-interwork
-  else
-    ifeq ($(TARGET_ARCH),x86)
-      crtbegin_dynamic_target_cflags := -m32
-    endif
-  endif
-GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_dynamic.o
-$(GEN): $(LOCAL_PATH)/arch-$(TARGET_ARCH)/bionic/crtbegin_dynamic.S
-	@mkdir -p $(dir $@)
-	$(TARGET_CC) $(crtbegin_dynamic_target_cflags) -o $@ -c $<
-ALL_GENERATED_SOURCES += $(GEN)
-endif
-
 include $(BUILD_SHARED_LIBRARY)
 
 
+# ========================================================
 # libc_debug.so
 # ========================================================
-
 include $(CLEAR_VARS)
 
-LOCAL_CFLAGS := $(libc_common_cflags)
-
-LOCAL_CFLAGS += -DUSE_DL_PREFIX -DMALLOC_LEAK_CHECK
+LOCAL_CFLAGS := \
+	$(libc_common_cflags) \
+	-DMALLOC_LEAK_CHECK
 
 LOCAL_C_INCLUDES := $(libc_common_c_includes)
 
 LOCAL_SRC_FILES := \
+	$(libc_arch_dynamic_src_files) \
 	bionic/dlmalloc.c \
 	bionic/malloc_leak.c.arm \
 	bionic/libc_init_dynamic.c
 
-ifeq ($(TARGET_ARCH),arm)
-LOCAL_SRC_FILES += \
-	arch-arm/bionic/exidx_dynamic.c
-endif
-
 LOCAL_MODULE:= libc_debug
 
 # WARNING: The only library libc.so should depend on is libdl.so!  If you add other libraries,
@@ -564,9 +535,6 @@ LOCAL_PRELINK_MODULE := false
 # Don't install on release build
 LOCAL_MODULE_TAGS := eng
 
-GEN := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_dynamic.o
-ALL_GENERATED_SOURCES += $(GEN)
-
 include $(BUILD_SHARED_LIBRARY)
 
 # ========================================================