Revert "Remove env-var-allowlist"

Revert "Add -fdebug-compilation-dir option"

Revert submission 1461902-debug-compilation-dir

Reason for revert: "-Xclang" isn't being uniformly respected everywhere. For example, in ".S" compilations, when I pass `-Xclang -fdebug-compilation-dir=.", the assembler seems to be ignoring it and then inserting the `pwd` into the command, however when I pass "-fdebug-compilation-dir=.", it strips out the path to the current working directory.
This indicates that we need to update re-client's input processor so that we can pass -fdebug-compilation-dir=. without "-Xclang" and then remove `PWD` setting.
For now, I'll update this patch to pass both "-fdebug-compilation-dir=." and `PWD` and when RBE side fix is done, I'll remove `PWD` in a separate CL.

Reverted Changes:
Ib0f271e55:Add -fdebug-compilation-dir option
Ifa0592af5:Remove env-var-allowlist

Change-Id: I7c690b3e00d37dbcc8fbaa66dda49f39032be3ab

core/config.mk

@@ -996,6 +996,16 @@ endif # PRODUCT_USE_DYNAMIC_PARTITIONS
 # Set up final options.
 # ###############################################################
 
+# 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
+else
+RELATIVE_PWD :=
+endif
+
 # Flags for DEX2OAT
 first_non_empty_of_three = $(if $(1),$(1),$(if $(2),$(2),$(3)))
 DEX2OAT_TARGET_ARCH := $(TARGET_ARCH)

core/definitions.mk

@@ -1179,7 +1179,7 @@ define transform-cpp-to-o
 @echo "$($(PRIVATE_PREFIX)DISPLAY) $(PRIVATE_ARM_MODE) C++: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
 $(if $(PRIVATE_TIDY_CHECKS),$(clang-tidy-cpp))
-$(hide) $(PRIVATE_CXX) \
+$(hide) $(RELATIVE_PWD) $(PRIVATE_CXX) \
   $(transform-cpp-to-o-compiler-args) \
   -MD -MF $(patsubst %.o,%.d,$@) -o $@ $<
 endef
@@ -1225,7 +1225,7 @@ define transform-c-to-o
 @echo "$($(PRIVATE_PREFIX)DISPLAY) $(PRIVATE_ARM_MODE) C: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
 $(if $(PRIVATE_TIDY_CHECKS),$(clang-tidy-c))
-$(hide) $(PRIVATE_CC) \
+$(hide) $(RELATIVE_PWD) $(PRIVATE_CC) \
   $(transform-c-to-o-compiler-args) \
   -MD -MF $(patsubst %.o,%.d,$@) -o $@ $<
 endef
@@ -1234,7 +1234,7 @@ endif
 define transform-s-to-o
 @echo "$($(PRIVATE_PREFIX)DISPLAY) asm: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
-$(PRIVATE_CC) \
+$(RELATIVE_PWD) $(PRIVATE_CC) \
   $(call transform-c-or-s-to-o-compiler-args, $(PRIVATE_ASFLAGS)) \
   -MD -MF $(patsubst %.o,%.d,$@) -o $@ $<
 endef
@@ -1293,7 +1293,7 @@ define transform-host-cpp-to-o
 @echo "$($(PRIVATE_PREFIX)DISPLAY) C++: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
 $(if $(PRIVATE_TIDY_CHECKS),$(clang-tidy-host-cpp))
-$(hide) $(PRIVATE_CXX) \
+$(hide) $(RELATIVE_PWD) $(PRIVATE_CXX) \
   $(transform-host-cpp-to-o-compiler-args) \
   -MD -MF $(patsubst %.o,%.d,$@) -o $@ $<
 endef
@@ -1316,7 +1316,7 @@ endef
 # $(1): extra flags
 define transform-host-c-or-s-to-o
 @mkdir -p $(dir $@)
-$(hide) $(PRIVATE_CC) \
+$(hide) $(RELATIVE_PWD) $(PRIVATE_CC) \
   $(transform-host-c-or-s-to-o-common-args) \
   $(1) \
   -MD -MF $(patsubst %.o,%.d,$@) -o $@ $<
@@ -1343,7 +1343,7 @@ define transform-host-c-to-o
 @echo "$($(PRIVATE_PREFIX)DISPLAY) C: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
 $(if $(PRIVATE_TIDY_CHECKS), $(clang-tidy-host-c))
-$(hide) $(PRIVATE_CC) \
+$(hide) $(RELATIVE_PWD) $(PRIVATE_CC) \
   $(transform-host-c-to-o-compiler-args) \
   -MD -MF $(patsubst %.o,%.d,$@) -o $@ $<
 endef

core/rbe.mk

@@ -57,7 +57,7 @@ ifneq ($(filter-out false,$(USE_RBE)),)
   java_r8_d8_platform := $(platform),Pool=java16
 
   RBE_WRAPPER := $(rbe_dir)/rewrapper
-  RBE_CXX := --labels=type=compile,lang=cpp,compiler=clang --exec_strategy=$(cxx_rbe_exec_strategy) --platform=$(cxx_platform) --compare=$(cxx_compare)
+  RBE_CXX := --labels=type=compile,lang=cpp,compiler=clang --env_var_allowlist=PWD --exec_strategy=$(cxx_rbe_exec_strategy) --platform=$(cxx_platform) --compare=$(cxx_compare)
 
   # Append rewrapper to existing *_WRAPPER variables so it's possible to
   # use both ccache and rewrapper.