cmPolicies: Implement PolicyMap in terms of bitset.

1 files changed, 11 insertions, 1 deletions

diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 46b725ac56..63376dd7dc 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -14,6 +14,8 @@
 
 #include "cmCustomCommand.h"
 
+#include <bitset>
+
 class cmMakefile;
 class cmPolicy;
 
@@ -268,12 +270,20 @@ public:
   static std::string GetRequiredAlwaysPolicyError(cmPolicies::PolicyID id);
 
   /** Represent a set of policy values.  */
-  struct PolicyMap : private std::map<PolicyID, PolicyStatus>
+  struct PolicyMap
   {
+    PolicyMap();
     PolicyStatus Get(PolicyID id) const;
     void Set(PolicyID id, PolicyStatus status);
     bool IsDefined(PolicyID id) const;
     bool IsEmpty() const;
+
+  private:
+    std::bitset<cmPolicies::CMPCOUNT> UNDEFINED;
+    std::bitset<cmPolicies::CMPCOUNT> OLD;
+    std::bitset<cmPolicies::CMPCOUNT> NEW;
+    std::bitset<cmPolicies::CMPCOUNT> REQUIRED_IF_USED;
+    std::bitset<cmPolicies::CMPCOUNT> REQUIRED_ALWAYS;
   };
 };