Avoid duplicate ZERO_CHECK in VS solutions

The commit "Avoid non-root copies of root-only targets" moved the check
for root-only targets into cmGlobalGenerator::GetTargetSets to avoid
adding multiple ALL_BUILD targets to the "original" target set.  This
approach did not work for ZERO_CHECK targets though because those are
pulled in by dependency analysis.

Instead we eliminate duplicate ZERO_CHECK targets altogether and refer
to a single one from all solution files.  This cleans up VS 10 project
file references to ZERO_CHECK targets anyway.

Source/cmGlobalVisualStudio7Generator.cxx

@@ -615,13 +615,6 @@ cmGlobalVisualStudio7Generator
     }
 }
 
-//----------------------------------------------------------------------------
-bool cmGlobalVisualStudio7Generator::IsRootOnlyTarget(cmTarget* target)
-{
-  return (this->cmGlobalVisualStudioGenerator::IsRootOnlyTarget(target) ||
-          strcmp(target->GetName(), CMAKE_CHECK_BUILD_SYSTEM_TARGET) == 0);
-}
-
 bool cmGlobalVisualStudio7Generator::IsPartOfDefaultBuild(const char* project,
                                                           cmTarget* target)
 {

Source/cmGlobalVisualStudio7Generator.h

@@ -133,7 +133,6 @@ protected:
 
   std::string ConvertToSolutionPath(const char* path);
 
-  virtual bool IsRootOnlyTarget(cmTarget* target);
   bool IsPartOfDefaultBuild(const char* project,
                             cmTarget* target);
   std::vector<std::string> Configurations;

Source/cmGlobalVisualStudio8Generator.cxx

@@ -110,20 +110,13 @@ std::string cmGlobalVisualStudio8Generator::GetUserMacrosRegKeyBase()
 }
 
 //----------------------------------------------------------------------------
-void cmGlobalVisualStudio8Generator::Generate()
+void cmGlobalVisualStudio8Generator::AddCheckTarget()
 {
   // Add a special target on which all other targets depend that
   // checks the build system and optionally re-runs CMake.
   const char* no_working_directory = 0;
   std::vector<std::string> no_depends;
-  std::map<cmStdString, std::vector<cmLocalGenerator*> >::iterator it;
+  std::vector<cmLocalGenerator*> const& generators = this->LocalGenerators;
-  for(it = this->ProjectMap.begin(); it!= this->ProjectMap.end(); ++it)
-    {
-    std::vector<cmLocalGenerator*>& generators = it->second;
-    if(!generators.empty())
-      {
-      // Add the build-system check target to the first local
-      // generator of this project.
   cmLocalVisualStudio7Generator* lg =
     static_cast<cmLocalVisualStudio7Generator*>(generators[0]);
   cmMakefile* mf = lg->GetMakefile();
@@ -131,21 +124,15 @@ void cmGlobalVisualStudio8Generator::Generate()
   // Skip the target if no regeneration is to be done.
   if(mf->IsOn("CMAKE_SUPPRESS_REGENERATION"))
     {
-        continue;
+    return;
     }
 
   std::string cmake_command = mf->GetRequiredDefinition("CMAKE_COMMAND");
   cmCustomCommandLines noCommandLines;
+  cmTarget* tgt =
     mf->AddUtilityCommand(CMAKE_CHECK_BUILD_SYSTEM_TARGET, false,
                           no_working_directory, no_depends,
                           noCommandLines);
-      cmTarget* tgt = mf->FindTarget(CMAKE_CHECK_BUILD_SYSTEM_TARGET);
-      if(!tgt)
-        {
-        cmSystemTools::Error("Error adding target " 
-                             CMAKE_CHECK_BUILD_SYSTEM_TARGET);
-        continue;
-        }
 
   // Create a list of all stamp files for this project.
   std::vector<std::string> stamps;
@@ -235,7 +222,11 @@ void cmGlobalVisualStudio8Generator::Generate()
     }
   }
 }
-    }
+
+//----------------------------------------------------------------------------
+void cmGlobalVisualStudio8Generator::Generate()
+{
+  this->AddCheckTarget();
 
   // All targets depend on the build-system check target.
   for(std::map<cmStdString,cmTarget *>::const_iterator

Source/cmGlobalVisualStudio8Generator.h

@@ -63,6 +63,8 @@ protected:
 
   virtual bool VSLinksDependencies() const { return false; }
 
+  void AddCheckTarget();
+
   static cmIDEFlagTable const* GetExtraFlagTableVS8();
   virtual void AddPlatformDefinitions(cmMakefile* mf);
   virtual void WriteSLNHeader(std::ostream& fout);