diff --git a/src/libCom/test/Makefile b/src/libCom/test/Makefile
index 927373f7e..ca5386510 100644
--- a/src/libCom/test/Makefile
+++ b/src/libCom/test/Makefile
@@ -198,8 +198,8 @@ cvtFastPerform_SRCS += cvtFastPerform.cpp
 testHarness_SRCS += cvtFastPerform.cpp
 
 TESTPROD_HOST_Linux += epicsMutexPriorityInversionTest
-epicsMutexPriorityInversionTest_SRCS += epicsMutexPriorityInversionTest.cc
-epicsMutexPriorityInversionTest_SYS_LIBS_Linux += pthread
+epicsMutexPriorityInversionTest_SRCS += epicsMutexPriorityInversionTest.c
+epicsMutexPriorityInversionTest_SYS_LIBS_Linux += pthread rt
 TESTSCRIPTS_HOST_Linux+=epicsMutexPriorityInversionTest.t
 
 include $(TOP)/configure/RULES
diff --git a/src/libCom/test/epicsMutexPriorityInversionTest.cc b/src/libCom/test/epicsMutexPriorityInversionTest.c
similarity index 100%
rename from src/libCom/test/epicsMutexPriorityInversionTest.cc
rename to src/libCom/test/epicsMutexPriorityInversionTest.c