cmake: Future-proof --find-package mode.

Create cmGeneratorTargets before generating generate-time information.
C++ interfaces for querying build information is increasingly only
available at generate time through the cmGeneratorTarget class.  Ensure
that the required cmGeneratorTarget instances are created.  Use the
cmGlobalGenerator access API to access the relevant cmGeneratorTarget
instead of creating a temporary one on the stack.

Source/cmGlobalGenerator.cxx

@@ -1375,15 +1375,9 @@ void cmGlobalGenerator::FinalizeTargetCompileInfo()
 }
 
 //----------------------------------------------------------------------------
-void cmGlobalGenerator::CreateGeneratorTargets()
+void cmGlobalGenerator::CreateGeneratorTargets(cmMakefile *mf)
-{
-  // Construct per-target generator information.
-  for(unsigned int i=0; i < this->LocalGenerators.size(); ++i)
 {
   cmGeneratorTargetsType generatorTargets;
-
-    cmMakefile *mf = this->LocalGenerators[i]->GetMakefile();
-
   cmTargets& targets = mf->GetTargets();
   for(cmTargets::iterator ti = targets.begin();
       ti != targets.end(); ++ti)
@@ -1402,9 +1396,17 @@ void cmGlobalGenerator::CreateGeneratorTargets()
     this->GeneratorTargets[*j] = gt;
     generatorTargets[*j] = gt;
     }
-
   mf->SetGeneratorTargets(generatorTargets);
 }
+
+//----------------------------------------------------------------------------
+void cmGlobalGenerator::CreateGeneratorTargets()
+{
+  // Construct per-target generator information.
+  for(unsigned int i=0; i < this->LocalGenerators.size(); ++i)
+    {
+    this->CreateGeneratorTargets(this->LocalGenerators[i]->GetMakefile());
+    }
 }
 
 //----------------------------------------------------------------------------

Source/cmGlobalGenerator.h

@@ -432,6 +432,8 @@ private:
 
   // Per-target generator information.
   cmGeneratorTargetsType GeneratorTargets;
+  friend class cmake;
+  void CreateGeneratorTargets(cmMakefile* mf);
   void CreateGeneratorTargets();
   void ComputeGeneratorTargetObjects();
   virtual void ComputeTargetObjects(cmGeneratorTarget* gt) const;

Source/cmake.cxx

@@ -593,9 +593,10 @@ bool cmake::FindPackage(const std::vector<std::string>& args)
     std::string linkPath;
     std::string flags;
     std::string linkFlags;
-    cmGeneratorTarget gtgt(tgt);
+    gg->CreateGeneratorTargets(mf);
+    cmGeneratorTarget *gtgt = gg->GetGeneratorTarget(tgt);
     lg->GetTargetFlags(linkLibs, frameworkPath, linkPath, flags, linkFlags,
-                       &gtgt);
+                       gtgt);
     linkLibs = frameworkPath + linkPath + linkLibs;
 
     printf("%s\n", linkLibs.c_str() );