diff --git a/src/storm-pomdp/analysis/WinningRegion.cpp b/src/storm-pomdp/analysis/WinningRegion.cpp
index 7b872a20a..39d89c095 100644
--- a/src/storm-pomdp/analysis/WinningRegion.cpp
+++ b/src/storm-pomdp/analysis/WinningRegion.cpp
@@ -210,7 +210,7 @@ namespace pomdp {
             storm::RationalNumber n = 1;
             while (n < max) {
                 oom += 1;
-                n *= 2;
+                n = n * 2;
             }
             STORM_LOG_DEBUG("Order of magnitude = " << oom);
 
@@ -390,4 +390,4 @@ namespace pomdp {
     }
 
 }
-}
\ No newline at end of file
+}