Performance: remove Members indirection for Pipeline

include/qpdf/Pipeline.hh

@@ -78,26 +78,10 @@ class QPDF_DLL_CLASS Pipeline
     std::string identifier;
 
   private:
-    // Do not implement copy or assign
-    Pipeline(Pipeline const&);
-    Pipeline& operator=(Pipeline const&);
+    Pipeline(Pipeline const&) = delete;
+    Pipeline& operator=(Pipeline const&) = delete;
 
-    class Members
-    {
-        friend class Pipeline;
-
-      public:
-        QPDF_DLL
-        ~Members();
-
-      private:
-        Members(Pipeline* next);
-        Members(Members const&);
-
-        Pipeline* next;
-    };
-
-    PointerHolder<Members> m;
+    Pipeline* next;
 };
 
 #endif // PIPELINE_HH

libqpdf/Pipeline.cc

@@ -1,18 +1,9 @@
 #include <qpdf/Pipeline.hh>
 #include <stdexcept>
 
-Pipeline::Members::Members(Pipeline* next) :
-    next(next)
-{
-}
-
-Pipeline::Members::~Members()
-{
-}
-
 Pipeline::Pipeline(char const* identifier, Pipeline* next) :
     identifier(identifier),
-    m(new Members(next))
+    next(next)
 {
 }
 
@@ -23,13 +14,13 @@ Pipeline::~Pipeline()
 Pipeline*
 Pipeline::getNext(bool allow_null)
 {
-    if ((this->m->next == 0) && (! allow_null))
+    if ((this->next == 0) && (! allow_null))
     {
 	throw std::logic_error(
 	    this->identifier +
 	    ": Pipeline::getNext() called on pipeline with no next");
     }
-    return this->m->next;
+    return this->next;
 }
 
 std::string