Improve efficiency of ResolveRecorder

Removing an element from a set with iterator is constant time, and
std::set specifies that other operations on the set do not invalidate
existing iterators.

1 files changed, 3 insertions, 4 deletions

diff --git a/include/qpdf/QPDF.hh b/include/qpdf/QPDF.hh
index 1e3d4c34..8a861714 100644
--- a/include/qpdf/QPDF.hh
+++ b/include/qpdf/QPDF.hh
@@ -1063,18 +1063,17 @@ class QPDF
       public:
         ResolveRecorder(QPDF* qpdf, QPDFObjGen const& og) :
             qpdf(qpdf),
-            og(og)
+            iter(qpdf->m->resolving.insert(og).first)
         {
-            qpdf->m->resolving.insert(og);
         }
         virtual ~ResolveRecorder()
         {
-            this->qpdf->m->resolving.erase(og);
+            this->qpdf->m->resolving.erase(iter);
         }
 
       private:
         QPDF* qpdf;
-        QPDFObjGen og;
+        std::set<QPDFObjGen>::const_iterator iter;
     };
     friend class ResolveRecorder;