Merge "Add a SANITIZE_HOST flag."
diff --git a/core/binary.mk b/core/binary.mk
index 7fd7e32..752a5c3 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -191,19 +191,7 @@
 b_lib :=
 endif
 
-ifeq ($(strip $(LOCAL_ADDRESS_SANITIZER)),true)
-  my_clang := true
-  # Frame pointer based unwinder in ASan requires ARM frame setup.
-  LOCAL_ARM_MODE := arm
-  my_cflags += $(ADDRESS_SANITIZER_CONFIG_EXTRA_CFLAGS)
-  my_ldflags += $(ADDRESS_SANITIZER_CONFIG_EXTRA_LDFLAGS)
-  ifdef LOCAL_IS_HOST_MODULE
-      my_ldflags += -fsanitize=address
-  else
-      my_shared_libraries += $(ADDRESS_SANITIZER_CONFIG_EXTRA_SHARED_LIBRARIES)
-      my_static_libraries += $(ADDRESS_SANITIZER_CONFIG_EXTRA_STATIC_LIBRARIES)
-  endif
-endif
+include $(BUILD_SYSTEM)/config_sanitizers.mk
 
 ifeq ($(strip $($(LOCAL_2ND_ARCH_VAR_PREFIX)WITHOUT_$(my_prefix)CLANG)),true)
   my_clang :=
diff --git a/core/config_sanitizers.mk b/core/config_sanitizers.mk
new file mode 100644
index 0000000..a1964a9
--- /dev/null
+++ b/core/config_sanitizers.mk
@@ -0,0 +1,32 @@
+##############################################
+## Perform configuration steps for sanitizers.
+##############################################
+
+# Configure SANITIZE_HOST.
+ifdef LOCAL_IS_HOST_MODULE
+ifeq ($(SANITIZE_HOST),true)
+ifneq ($(strip $(LOCAL_CLANG)),false)
+ifneq ($(strip $(LOCAL_ADDRESS_SANITIZER)),false)
+    LOCAL_ADDRESS_SANITIZER := true
+endif
+endif
+endif
+endif
+
+# Configure address sanitizer.
+ifeq ($(strip $(LOCAL_ADDRESS_SANITIZER)),true)
+  my_clang := true
+  # Frame pointer based unwinder in ASan requires ARM frame setup.
+  LOCAL_ARM_MODE := arm
+  my_cflags += $(ADDRESS_SANITIZER_CONFIG_EXTRA_CFLAGS)
+  my_ldflags += $(ADDRESS_SANITIZER_CONFIG_EXTRA_LDFLAGS)
+  ifdef LOCAL_IS_HOST_MODULE
+      my_ldflags += -fsanitize=address
+      # -nodefaultlibs (provided with libc++) prevents the driver from linking
+      # libraries needed with -fsanitize=address. http://b/18650275
+      my_ldlibs += -ldl -lpthread
+  else
+      my_shared_libraries += $(ADDRESS_SANITIZER_CONFIG_EXTRA_SHARED_LIBRARIES)
+      my_static_libraries += $(ADDRESS_SANITIZER_CONFIG_EXTRA_STATIC_LIBRARIES)
+  endif
+endif
diff --git a/envsetup.sh b/envsetup.sh
index 0e853fe..9a540ef 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -17,6 +17,11 @@
 - sgrep:   Greps on all local source files.
 - godir:   Go to the directory containing a file.
 
+Environemnt options:
+- SANITIZE_HOST: Set to 'true' to use ASAN for all host modules. Note that
+                 ASAN_OPTIONS=detect_leaks=0 will be set by default until the
+                 build is leak-check clean.
+
 Look at the source to view more functions. The complete list is:
 EOF
     T=$(gettop)
@@ -231,6 +236,7 @@
     export ANDROID_BUILD_TOP=$(gettop)
     # With this environment variable new GCC can apply colors to warnings/errors
     export GCC_COLORS='error=01;31:warning=01;35:note=01;36:caret=01;32:locus=01:quote=01'
+    export ASAN_OPTIONS=detect_leaks=0
 }
 
 function set_sequence_number()