cmExportSetMap: improve ownership of cmExportSet

- use `std::piecewise_construct` to fix gcc-4.8 build.
- can use `emplace(name, name)` gcc-6 onwards.

1 files changed, 4 insertions, 18 deletions

diff --git a/Source/cmExportSetMap.cxx b/Source/cmExportSetMap.cxx
index 5c3f84f..68e76d5 100644
--- a/Source/cmExportSetMap.cxx
+++ b/Source/cmExportSetMap.cxx
@@ -2,30 +2,16 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmExportSetMap.h"
 
-#include "cmAlgorithms.h"
-#include "cmExportSet.h"
-
+#include <tuple>
 #include <utility>
 
-cmExportSet* cmExportSetMap::operator[](const std::string& name)
+cmExportSet& cmExportSetMap::operator[](const std::string& name)
 {
   auto it = this->find(name);
   if (it == this->end()) // Export set not found
   {
-    it = this->insert(std::make_pair(name, new cmExportSet(name))).first;
+    auto tup_name = std::make_tuple(name);
+    it = this->emplace(std::piecewise_construct, tup_name, tup_name).first;
   }
   return it->second;
 }
-
-void cmExportSetMap::clear()
-{
-  cmDeleteAll(*this);
-  this->derived::clear();
-}
-
-cmExportSetMap::cmExportSetMap() = default;
-
-cmExportSetMap::~cmExportSetMap()
-{
-  this->clear();
-}