diff --git a/src/misc/pv/reftrack.h b/src/misc/pv/reftrack.h
index d4b8052..30a07f4 100644
--- a/src/misc/pv/reftrack.h
+++ b/src/misc/pv/reftrack.h
@@ -59,9 +59,9 @@ public:
     //! A single count
     struct Count {
         size_t current;
-        ssize_t delta; //!< current - previous
+        long delta; //!< current - previous
         Count() :current(0u), delta(0) {}
-        explicit Count(size_t c, ssize_t d) :current(c), delta(d) {}
+        explicit Count(size_t c, long d) :current(c), delta(d) {}
         bool operator==(const Count& o) const
         { return current==o.current && delta==o.delta; }
     };
diff --git a/src/misc/reftrack.cpp b/src/misc/reftrack.cpp
index 2031620..00bd02b 100644
--- a/src/misc/reftrack.cpp
+++ b/src/misc/reftrack.cpp
@@ -133,7 +133,7 @@ RefSnapshot operator-(const RefSnapshot& lhs, const RefSnapshot& rhs)
     while(lit!=lend || rit!=rend)
     {
         if(lit==lend || (rit!=rend && lit->first > rit->first)) {
-            ret.counts[rit->first] = RefSnapshot::Count(0, -ssize_t(rit->second.current));
+            ret.counts[rit->first] = RefSnapshot::Count(0, -long(rit->second.current));
             ++rit;
 
         } else if(rit==rend || lit->first < rit->first) {
@@ -142,7 +142,7 @@ RefSnapshot operator-(const RefSnapshot& lhs, const RefSnapshot& rhs)
 
         } else { // !end and lit->first == rit->first
             ret.counts[lit->first] = RefSnapshot::Count(lit->second.current,
-                                                        ssize_t(lit->second.current) - ssize_t(rit->second.current));
+                                                        long(lit->second.current) - long(rit->second.current));
             ++lit;
             ++rit;
         }