diff --git a/configure/os/CONFIG.win32-x86-mingw.win32-x86-mingw b/configure/os/CONFIG.win32-x86-mingw.win32-x86-mingw
index 27e815dcf..a4f3f9e53 100644
--- a/configure/os/CONFIG.win32-x86-mingw.win32-x86-mingw
+++ b/configure/os/CONFIG.win32-x86-mingw.win32-x86-mingw
@@ -26,7 +26,7 @@ LOADABLE_SHRLIB_LDFLAGS = -shared -Wl,--out-implib,$(LIB_PREFIX)$*$(LIB_SUFFIX)
 # Override linking with gcc library from CONFIG.gnuCommon
 GNU_LDLIBS_YES =
 
-OPT_CFLAGS_NO = -O3 -g
-OPT_CXXFLAGS_NO = -O3 -g
+OPT_CFLAGS_NO = -g
+OPT_CXXFLAGS_NO = -g
 
 OP_SYS_LDLIBS = -lws2_32 
diff --git a/src/ca/bhe.cpp b/src/ca/bhe.cpp
index b1026052b..8ede482b4 100644
--- a/src/ca/bhe.cpp
+++ b/src/ca/bhe.cpp
@@ -360,6 +360,6 @@ void bheFreeStore::release ( void * pCadaver )
     freeList.release ( pCadaver );
 }
 
-epicsShareFunc bheMemoryManager::~bheMemoryManager () {}
+bheMemoryManager::~bheMemoryManager () {}
 
 
diff --git a/src/ca/bhe.h b/src/ca/bhe.h
index 75312e051..1660e485b 100644
--- a/src/ca/bhe.h
+++ b/src/ca/bhe.h
@@ -45,9 +45,9 @@ class bheMemoryManager;
 
 // using a pure abstract wrapper class around the free list avoids
 // Tornado 2.0.1 GNU compiler bugs
-class bheMemoryManager {
+class epicsShareClass bheMemoryManager {
 public:
-    epicsShareFunc virtual ~bheMemoryManager ();
+    virtual ~bheMemoryManager ();
     virtual void * allocate ( size_t ) = 0;
     virtual void release ( void * ) = 0;
 };
diff --git a/src/ca/repeaterSubscribeTimer.h b/src/ca/repeaterSubscribeTimer.h
index ee4332c43..0a23d16d3 100644
--- a/src/ca/repeaterSubscribeTimer.h
+++ b/src/ca/repeaterSubscribeTimer.h
@@ -28,6 +28,18 @@
 
 #include "epicsTimer.h"
 
+#ifdef epicsExportSharedSymbols
+#   define repeaterSubscribeTimerh_epicsExportSharedSymbols
+#   undef epicsExportSharedSymbols
+#endif
+
+#include "epicsTimer.h"
+
+#ifdef repeaterSubscribeTimerh_epicsExportSharedSymbols
+#   define epicsExportSharedSymbols
+#   include "shareLib.h"
+#endif
+
 class epicsMutex;
 class cacContextNotify;
 
diff --git a/src/ca/tcpRecvWatchdog.h b/src/ca/tcpRecvWatchdog.h
index 488cfac19..0b15e22d8 100644
--- a/src/ca/tcpRecvWatchdog.h
+++ b/src/ca/tcpRecvWatchdog.h
@@ -26,8 +26,18 @@
 #ifndef tcpRecvWatchdogh  
 #define tcpRecvWatchdogh
 
+#ifdef epicsExportSharedSymbols
+#   define tcpRecvWatchdogh_epicsExportSharedSymbols
+#   undef epicsExportSharedSymbols
+#endif
+
 #include "epicsTimer.h"
 
+#ifdef tcpRecvWatchdogh_epicsExportSharedSymbols
+#   define epicsExportSharedSymbols
+#   include "shareLib.h"
+#endif
+
 class tcpiiu;
 
 class tcpRecvWatchdog : private epicsTimerNotify {
diff --git a/src/ca/tcpSendWatchdog.h b/src/ca/tcpSendWatchdog.h
index 8b49e83bf..05a2dfe75 100644
--- a/src/ca/tcpSendWatchdog.h
+++ b/src/ca/tcpSendWatchdog.h
@@ -26,8 +26,19 @@
 #ifndef tcpSendWatchdogh  
 #define tcpSendWatchdogh
 
+
+#ifdef epicsExportSharedSymbols
+#   define tcpSendWatchdogh_epicsExportSharedSymbols
+#   undef epicsExportSharedSymbols
+#endif
+
 #include "epicsTimer.h"
 
+#ifdef tcpSendWatchdogh_epicsExportSharedSymbols
+#   define epicsExportSharedSymbols
+#   include "shareLib.h"
+#endif
+
 class tcpSendWatchdog : private epicsTimerNotify {
 public:
     tcpSendWatchdog (
diff --git a/src/libCom/timer/epicsTimer.h b/src/libCom/timer/epicsTimer.h
index 4c59467e0..769174bcc 100644
--- a/src/libCom/timer/epicsTimer.h
+++ b/src/libCom/timer/epicsTimer.h
@@ -28,7 +28,7 @@
  */
 
 /* code using a timer must implement epicsTimerNotify */
-class epicsTimerNotify {
+class epicsShareClass epicsTimerNotify {
 public:
     enum restart_t { noRestart, restart };
     class expireStatus {
@@ -41,13 +41,13 @@ public:
         double delay;
     };
 
-    epicsShareFunc virtual ~epicsTimerNotify () = 0;
+    virtual ~epicsTimerNotify () = 0;
     /* return "noRestart" or "expireStatus ( restart, 30.0 )" */
     virtual expireStatus expire ( const epicsTime & currentTime ) = 0;
-    epicsShareFunc virtual void show ( unsigned int level ) const;
+    virtual void show ( unsigned int level ) const;
 };
 
-class epicsTimer {              /* X aCC 655 */
+class epicsShareClass epicsTimer {              /* X aCC 655 */
 public:
     /* calls cancel (see warning below) and then destroys the timer */
     virtual void destroy () = 0;
@@ -67,7 +67,7 @@ public:
     double getExpireDelay ();
     virtual void show ( unsigned int level ) const = 0;
 protected:
-    epicsShareFunc virtual ~epicsTimer () = 0; /* protected => delete() must not be called */
+    virtual ~epicsTimer () = 0; /* protected => delete() must not be called */
 };
 
 class epicsTimerQueue {         /* X aCC 655 */