diff --git a/src/libCom/osi/os/WIN32/osdSignal.cpp b/src/libCom/osi/os/WIN32/osdSignal.cpp
index b8d5f213d..a826bab77 100644
--- a/src/libCom/osi/os/WIN32/osdSignal.cpp
+++ b/src/libCom/osi/os/WIN32/osdSignal.cpp
@@ -16,5 +16,5 @@
  */
 epicsShareFunc void epicsShareAPI epicsSignalInstallSigPipeIgnore ( void ) {}
 epicsShareFunc void epicsShareAPI epicsSignalInstallSigUrgIgnore ( void ) {}
-epicsShareFunc void epicsShareAPI epicsSignalRaiseSigUrg ( struct epicsThreadOSD * threadid ) {}
+epicsShareFunc void epicsShareAPI epicsSignalRaiseSigUrg ( struct epicsThreadOSD * /* threadid */ ) {}
 
diff --git a/src/libCom/osi/os/default/osdSignal.cpp b/src/libCom/osi/os/default/osdSignal.cpp
index 8d3afd3d7..673021d82 100644
--- a/src/libCom/osi/os/default/osdSignal.cpp
+++ b/src/libCom/osi/os/default/osdSignal.cpp
@@ -16,5 +16,5 @@
  */
 epicsShareFunc void epicsShareAPI epicsSignalInstallSigPipeIgnore ( void ) {}
 epicsShareFunc void epicsShareAPI epicsSignalInstallSigUrgIgnore ( void ) {}
-epicsShareFunc void epicsShareAPI epicsSignalRaiseSigUrg ( struct epicsThreadOSD * threadId ) {}
+epicsShareFunc void epicsShareAPI epicsSignalRaiseSigUrg ( struct epicsThreadOSD * /* threadId */ ) {}
 
diff --git a/src/libCom/osi/os/vxWorks/osdSignal.cpp b/src/libCom/osi/os/vxWorks/osdSignal.cpp
index 5f4cc7943..5948bab9f 100644
--- a/src/libCom/osi/os/vxWorks/osdSignal.cpp
+++ b/src/libCom/osi/os/vxWorks/osdSignal.cpp
@@ -16,4 +16,4 @@
  */
 epicsShareFunc void epicsShareAPI epicsSignalInstallSigPipeIgnore ( void ) {}
 epicsShareFunc void epicsShareAPI epicsSignalInstallSigUrgIgnore ( void ) {}
-epicsShareFunc void epicsShareAPI epicsSignalRaiseSigUrg ( struct epicsThreadOSD * threadId ) {}
+epicsShareFunc void epicsShareAPI epicsSignalRaiseSigUrg ( struct epicsThreadOSD * /* threadId */ ) {}