diff --git a/SystemInformation.cxx b/SystemInformation.cxx
index 0460b2906fbf7d71e65936ec11d2a9823ab39c70..e61a1dc6e815781bb7229d6c4e7b1ac4c7b58615 100644
--- a/SystemInformation.cxx
+++ b/SystemInformation.cxx
@@ -3026,7 +3026,7 @@ bool SystemInformationImplementation::QueryProcessor()
     return false;
     }
 
-  this->NumberOfPhysicalCPU = c;
+  this->NumberOfPhysicalCPU = static_cast<unsigned int>(c);
   this->NumberOfLogicalCPU = this->NumberOfPhysicalCPU;
 
   return true;