--- a/make/RunTests.gmk	Mon Jan 28 18:49:34 2019 +0000
+++ b/make/RunTests.gmk	Mon Jan 28 03:51:38 2019 -0800
@@ -119,10 +119,8 @@
   JCOV_REPORT := $(JCOV_OUTPUT_DIR)/report
   JCOV_MEM_OPTIONS := -Xms64m -Xmx4g
 
-  ifneq ($(JCOV_IMAGE_DIR), )
-    # Replace our normal test JDK with the JCov image, if present.
-    JDK_UNDER_TEST := $(JCOV_IMAGE_DIR)
-  endif
+  # Replace our normal test JDK with the JCov image.
+  JDK_UNDER_TEST := $(JCOV_IMAGE_DIR)
 
   JCOV_ENVIRONMENT := JAVA_TOOL_OPTIONS="$(JCOV_MEM_OPTIONS)" \
       _JAVA_OPTIONS="$(JCOV_MEM_OPTIONS)"