diff --git a/core/main.mk b/core/main.mk
index 7793889..8738fd0 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -102,6 +102,15 @@
 EMMA_INSTRUMENT := true
 endif
 
+# TODO(b/158212027): Turn this into an error when all users have been moved to
+# `NATIVE_COVERAGE_PATHS` and `NATIVE_COVERAGE_EXCLUDE_PATHS`.
+ifneq ($(COVERAGE_PATHS),)
+  $(warning Variable COVERAGE_PATHS is deprecated. Please use NATIVE_COVERAGE_PATHS instead.)
+endif
+ifneq ($(COVERAGE_EXCLUDE_PATHS),)
+  $(warning Variable COVERAGE_EXCLUDE_PATHS is deprecated. Please use NATIVE_COVERAGE_EXCLUDE_PATHS instead.)
+endif
+
 ifeq (true,$(EMMA_INSTRUMENT))
 # Adding the jacoco library can cause the inclusion of
 # some typically banned classes