Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6a66a887 authored by Dan Willemsen's avatar Dan Willemsen
Browse files

Stop encoding absolute paths in symbols 

GCC & Clang encode the current working directory into the symbol files.
Even if the binaries are stripped before being installed, the build-id
hash will be different. This means that two different checkouts will
produce different installed binaries, even if the sources are identical.

To prevent this, set PWD=/proc/self/cwd, so that it replaces the
absolute path with the static path /proc/self/cwd. With GCC, use
-fdebug-prefix-map to remove that static path. Our clang does not yet
support this flag, but it was merged in r250094.

This does change the behavior when using gdb -- you now need to be in
$ANDROID_BUILD_TOP before gdb will load the sources.

Bug: 24204119
Change-Id: I792d65b042b7a3fdc78d567c5a6e93cdf0141b9b
parent 37572684

core/clang/config.mk

+2 −1
Original line number Diff line number Diff line
@@ -78,7 +78,8 @@ CLANG_CONFIG_UNKNOWN_CFLAGS := \ 
  -Wno-unused-local-typedefs \

  -Wunused-but-set-parameter \

  -Wunused-but-set-variable \

  -fdiagnostics-color

  -fdiagnostics-color \

  -fdebug-prefix-map=/proc/self/cwd=



# Clang flags for all host rules

CLANG_CONFIG_HOST_EXTRA_ASFLAGS :=

core/config.mk

+13 −0
Original line number Diff line number Diff line
@@ -176,6 +176,19 @@ include $(BUILD_SYSTEM)/envsetup.mk 
# See envsetup.mk for a description of SCAN_EXCLUDE_DIRS

FIND_LEAVES_EXCLUDES := $(addprefix --prune=, $(OUT_DIR) $(SCAN_EXCLUDE_DIRS) .repo .git)



# ---------------------------------------------------------------

# We run gcc/clang with PWD=/proc/self/cwd to remove the $TOP

# from the debug output. That way two builds in two different

# directories will create the same output.

# /proc doesn't exist on Darwin.

ifeq ($(HOST_OS),linux)

RELATIVE_PWD := PWD=/proc/self/cwd

# Remove this useless prefix from the debug output.

COMMON_GLOBAL_CFLAGS += -fdebug-prefix-map=/proc/self/cwd=

else

RELATIVE_PWD :=

endif



# ---------------------------------------------------------------

# Allow the C/C++ macros __DATE__ and __TIME__ to be set to the

# build date and time, so that a build may be repeated.

core/definitions.mk

+4 −4
Original line number Diff line number Diff line
@@ -1049,7 +1049,7 @@ endef 
define transform-cpp-to-o

@echo "target $(PRIVATE_ARM_MODE) C++: $(PRIVATE_MODULE) <= $<"

@mkdir -p $(dir $@)

$(hide) $(PRIVATE_CXX) \

$(hide) $(RELATIVE_PWD) $(PRIVATE_CXX) \

	$(addprefix -I , $(PRIVATE_C_INCLUDES)) \

	$(shell cat $(PRIVATE_IMPORT_INCLUDES)) \

	$(addprefix -isystem ,\
@@ -1081,7 +1081,7 @@ endef 
# $(1): extra flags

define transform-c-or-s-to-o-no-deps

@mkdir -p $(dir $@)

$(hide) $(PRIVATE_CC) \

$(hide) $(RELATIVE_PWD) $(PRIVATE_CC) \

	$(addprefix -I , $(PRIVATE_C_INCLUDES)) \

	$(shell cat $(PRIVATE_IMPORT_INCLUDES)) \

	$(addprefix -isystem ,\
@@ -1156,7 +1156,7 @@ endef 
define transform-host-cpp-to-o

@echo "$($(PRIVATE_PREFIX)DISPLAY) C++: $(PRIVATE_MODULE) <= $<"

@mkdir -p $(dir $@)

$(hide) $(PRIVATE_CXX) \

$(hide) $(RELATIVE_PWD) $(PRIVATE_CXX) \

	$(addprefix -I , $(PRIVATE_C_INCLUDES)) \

	$(shell cat $(PRIVATE_IMPORT_INCLUDES)) \

	$(addprefix -isystem ,\
@@ -1186,7 +1186,7 @@ endef 
# $(1): extra flags

define transform-host-c-or-s-to-o-no-deps

@mkdir -p $(dir $@)

$(hide) $(PRIVATE_CC) \

$(hide) $(RELATIVE_PWD) $(PRIVATE_CC) \

	$(addprefix -I , $(PRIVATE_C_INCLUDES)) \

	$(shell cat $(PRIVATE_IMPORT_INCLUDES)) \

	$(addprefix -isystem ,\