cmLocalGenerator: Require a valid cmState::Snapshot in the ctor.

Refactor the local generator creation API to accept a
cmState::Snapshot.  Adjust MakeLocalGenerator to use the 'current'
snapshot in cases where there is no parent.  Create the snapshot
for subdirectories in cmMakefile::AddSubdirectory.

This means that snapshots are now created at the point of extending the tree,
as appropriate, and independently of the cmLocalGenerator and cmMakefile they
represent the state for.

Source/cmGlobalBorlandMakefileGenerator.cxx

@@ -44,10 +44,10 @@ void cmGlobalBorlandMakefileGenerator
 
 ///! Create a local generator appropriate to this Global Generator
 cmLocalGenerator *cmGlobalBorlandMakefileGenerator::CreateLocalGenerator(
-    cmLocalGenerator* parent)
+    cmLocalGenerator* parent, cmState::Snapshot snapshot)
 {
   cmLocalUnixMakefileGenerator3* lg =
-      new cmLocalUnixMakefileGenerator3(this, parent);
+      new cmLocalUnixMakefileGenerator3(this, parent, snapshot);
   lg->SetMakefileVariableSize(32);
   lg->SetMakeCommandEscapeTargetTwice(true);
   lg->SetBorlandMakeCurlyHack(true);

Source/cmGlobalBorlandMakefileGenerator.h

@@ -36,7 +36,8 @@ public:
   static void GetDocumentation(cmDocumentationEntry& entry);
 
   ///! Create a local generator appropriate to this Global Generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /**
    * Try to determine system information such as shared library

Source/cmGlobalGenerator.cxx

@@ -1884,15 +1884,22 @@ void cmGlobalGenerator::EnableInstallTarget()
 }
 
 cmLocalGenerator *
-cmGlobalGenerator::MakeLocalGenerator(cmLocalGenerator *parent)
+cmGlobalGenerator::MakeLocalGenerator(cmState::Snapshot snapshot,
+                                      cmLocalGenerator *parent)
 {
-  return this->CreateLocalGenerator(parent);
+  if (!snapshot.IsValid())
+    {
+    snapshot = this->CMakeInstance->GetCurrentSnapshot();
+    }
+
+  return this->CreateLocalGenerator(parent, snapshot);
 }
 
-cmLocalGenerator *
-cmGlobalGenerator::CreateLocalGenerator(cmLocalGenerator *parent)
+cmLocalGenerator*
+cmGlobalGenerator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                        cmState::Snapshot snapshot)
 {
-  return new cmLocalGenerator(this, parent);
+  return new cmLocalGenerator(this, parent, snapshot);
 }
 
 void cmGlobalGenerator::EnableLanguagesFromGenerator(cmGlobalGenerator *gen,

Source/cmGlobalGenerator.h

@@ -21,6 +21,7 @@
 #include "cmExportSetMap.h" // For cmExportSetMap
 #include "cmGeneratorTarget.h"
 #include "cmGeneratorExpression.h"
+#include "cmState.h"
 
 #if defined(CMAKE_BUILD_WITH_CMAKE)
 # include "cmFileLockPool.h"
@@ -56,7 +57,9 @@ public:
   cmGlobalGenerator(cmake* cm);
   virtual ~cmGlobalGenerator();
 
-  cmLocalGenerator* MakeLocalGenerator(cmLocalGenerator* parent = 0);
+  cmLocalGenerator* MakeLocalGenerator(
+      cmState::Snapshot snapshot = cmState::Snapshot(),
+      cmLocalGenerator* parent = 0);
 
   ///! Get the name for this generator
   virtual std::string GetName() const { return "Generic"; }
@@ -441,7 +444,8 @@ protected:
 
 private:
   ///! Create a local generator appropriate to this Global Generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   cmMakefile* TryCompileOuterMakefile;
   float FirstTimeProgress;

Source/cmGlobalGhsMultiGenerator.cxx

@@ -33,9 +33,10 @@ cmGlobalGhsMultiGenerator::~cmGlobalGhsMultiGenerator()
 }
 
 cmLocalGenerator *
-cmGlobalGhsMultiGenerator::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalGhsMultiGenerator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                                cmState::Snapshot snapshot)
 {
-  return new cmLocalGhsMultiGenerator(this, parent);
+  return new cmLocalGhsMultiGenerator(this, parent, snapshot);
 }
 
 void cmGlobalGhsMultiGenerator::GetDocumentation(cmDocumentationEntry &entry)

Source/cmGlobalGhsMultiGenerator.h

@@ -31,7 +31,8 @@ public:
   { return new cmGlobalGeneratorSimpleFactory<cmGlobalGhsMultiGenerator>(); }
 
   ///! create the correct local generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /// @return the name of this generator.
   static std::string GetActualName() { return "Green Hills MULTI"; }

Source/cmGlobalNinjaGenerator.cxx

@@ -529,9 +529,10 @@ cmGlobalNinjaGenerator::cmGlobalNinjaGenerator(cmake* cm)
 // Virtual public methods.
 
 cmLocalGenerator*
-cmGlobalNinjaGenerator::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalNinjaGenerator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                             cmState::Snapshot snapshot)
 {
-  return new cmLocalNinjaGenerator(this, parent);
+  return new cmLocalNinjaGenerator(this, parent, snapshot);
 }
 
 void cmGlobalNinjaGenerator

Source/cmGlobalNinjaGenerator.h

@@ -170,7 +170,8 @@ public:
   virtual ~cmGlobalNinjaGenerator() { }
 
   /// Overloaded methods. @see cmGlobalGenerator::CreateLocalGenerator()
-  virtual cmLocalGenerator* CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator* CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /// Overloaded methods. @see cmGlobalGenerator::GetName().
   virtual std::string GetName() const {

Source/cmGlobalUnixMakefileGenerator3.cxx

@@ -60,9 +60,10 @@ void cmGlobalUnixMakefileGenerator3
 
 ///! Create a local generator appropriate to this Global Generator
 cmLocalGenerator *
-cmGlobalUnixMakefileGenerator3::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalUnixMakefileGenerator3::CreateLocalGenerator(cmLocalGenerator* parent,
+                                                   cmState::Snapshot snapshot)
 {
-  return new cmLocalUnixMakefileGenerator3(this, parent);
+  return new cmLocalUnixMakefileGenerator3(this, parent, snapshot);
 }
 
 //----------------------------------------------------------------------------

Source/cmGlobalUnixMakefileGenerator3.h

@@ -68,7 +68,8 @@ public:
   static void GetDocumentation(cmDocumentationEntry& entry);
 
   ///! Create a local generator appropriate to this Global Generator3
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /**
    * Try to determine system information such as shared library

Source/cmGlobalVisualStudio10Generator.cxx

@@ -307,9 +307,10 @@ void cmGlobalVisualStudio10Generator::WriteSLNHeader(std::ostream& fout)
 
 ///! Create a local generator appropriate to this Global Generator
 cmLocalGenerator *
-cmGlobalVisualStudio10Generator::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalVisualStudio10Generator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                                    cmState::Snapshot snapshot)
 {
-  return new cmLocalVisualStudio10Generator(this, parent);
+  return new cmLocalVisualStudio10Generator(this, parent, snapshot);
 }
 
 //----------------------------------------------------------------------------

Source/cmGlobalVisualStudio10Generator.h

@@ -46,7 +46,8 @@ public:
     );
 
   ///! create the correct local generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /**
    * Try to determine system information such as shared library

Source/cmGlobalVisualStudio6Generator.cxx

@@ -173,9 +173,10 @@ cmGlobalVisualStudio6Generator::GenerateBuildCommand(
 
 ///! Create a local generator appropriate to this Global Generator
 cmLocalGenerator *
-cmGlobalVisualStudio6Generator::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalVisualStudio6Generator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                                   cmState::Snapshot snapshot)
 {
-  return new cmLocalVisualStudio6Generator(this, parent);
+  return new cmLocalVisualStudio6Generator(this, parent, snapshot);
 }
 
 

Source/cmGlobalVisualStudio6Generator.h

@@ -39,7 +39,8 @@ public:
   static void GetDocumentation(cmDocumentationEntry& entry);
 
   ///! Create a local generator appropriate to this Global Generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /**
    * Try to determine system information such as shared library

Source/cmGlobalVisualStudio7Generator.cxx

@@ -279,10 +279,11 @@ void cmGlobalVisualStudio7Generator::GenerateBuildCommand(
 
 ///! Create a local generator appropriate to this Global Generator
 cmLocalGenerator *
-cmGlobalVisualStudio7Generator::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalVisualStudio7Generator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                                   cmState::Snapshot snapshot)
 {
   cmLocalVisualStudio7Generator *lg =
-    new cmLocalVisualStudio7Generator(this, parent);
+    new cmLocalVisualStudio7Generator(this, parent, snapshot);
   return lg;
 }
 

Source/cmGlobalVisualStudio7Generator.h

@@ -43,7 +43,8 @@ public:
   std::string const& GetPlatformName() const;
 
   ///! Create a local generator appropriate to this Global Generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   virtual bool SetSystemName(std::string const& s, cmMakefile* mf);
 

Source/cmGlobalXCodeGenerator.cxx

@@ -371,9 +371,10 @@ cmGlobalXCodeGenerator::GenerateBuildCommand(
 //----------------------------------------------------------------------------
 ///! Create a local generator appropriate to this Global Generator
 cmLocalGenerator *
-cmGlobalXCodeGenerator::CreateLocalGenerator(cmLocalGenerator* parent)
+cmGlobalXCodeGenerator::CreateLocalGenerator(cmLocalGenerator* parent,
+                                             cmState::Snapshot snapshot)
 {
-  return new cmLocalXCodeGenerator(this, parent);
+  return new cmLocalXCodeGenerator(this, parent, snapshot);
 }
 
 //----------------------------------------------------------------------------

Source/cmGlobalXCodeGenerator.h

@@ -41,7 +41,8 @@ public:
   static void GetDocumentation(cmDocumentationEntry& entry);
 
   ///! Create a local generator appropriate to this Global Generator
-  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent = 0);
+  virtual cmLocalGenerator *CreateLocalGenerator(cmLocalGenerator* parent,
+                                                 cmState::Snapshot snapshot);
 
   /**
    * Try to determine system information such as shared library

Source/cmLocalGenerator.cxx

@@ -44,19 +44,16 @@
 #endif
 
 cmLocalGenerator::cmLocalGenerator(cmGlobalGenerator* gg,
-                                   cmLocalGenerator* parent)
+                                   cmLocalGenerator* parent,
+                                   cmState::Snapshot snapshot)
+  : StateSnapshot(snapshot)
 {
+  assert(snapshot.IsValid());
   this->GlobalGenerator = gg;
   this->Parent = parent;
   if (parent)
     {
     parent->AddChild(this);
-    this->StateSnapshot =
-        this->GetState()->CreateSnapshot(parent->StateSnapshot);
-    }
-  else
-    {
-    this->StateSnapshot = gg->GetCMakeInstance()->GetCurrentSnapshot();
     }
 
   this->Makefile = new cmMakefile(this);

Source/cmLocalGenerator.h

@@ -34,7 +34,8 @@ class cmCustomCommandGenerator;
 class cmLocalGenerator
 {
 public:
-  cmLocalGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent);
+  cmLocalGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent,
+                   cmState::Snapshot snapshot);
   virtual ~cmLocalGenerator();
 
   /// @return whether we are processing the top CMakeLists.txt file.

Source/cmLocalGhsMultiGenerator.cxx

@@ -17,8 +17,9 @@
 #include "cmGeneratedFileStream.h"
 
 cmLocalGhsMultiGenerator::cmLocalGhsMultiGenerator(cmGlobalGenerator* gg,
-                                                   cmLocalGenerator* parent)
-  : cmLocalGenerator(gg, parent)
+                                                   cmLocalGenerator* parent,
+                                                   cmState::Snapshot snapshot)
+  : cmLocalGenerator(gg, parent, snapshot)
 {
 }
 

Source/cmLocalGhsMultiGenerator.h

@@ -25,7 +25,8 @@ class cmGeneratedFileStream;
 class cmLocalGhsMultiGenerator : public cmLocalGenerator
 {
 public:
-  cmLocalGhsMultiGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent);
+  cmLocalGhsMultiGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent,
+                           cmState::Snapshot snapshot);
 
   virtual ~cmLocalGhsMultiGenerator();
 

Source/cmLocalNinjaGenerator.cxx

@@ -23,8 +23,9 @@
 #include <assert.h>
 
 cmLocalNinjaGenerator::cmLocalNinjaGenerator(cmGlobalGenerator* gg,
-                                             cmLocalGenerator* parent)
-  : cmLocalGenerator(gg, parent)
+                                             cmLocalGenerator* parent,
+                                             cmState::Snapshot snapshot)
+  : cmLocalGenerator(gg, parent, snapshot)
   , ConfigName("")
   , HomeRelativeOutputPath("")
 {

Source/cmLocalNinjaGenerator.h

@@ -31,7 +31,8 @@ class cmake;
 class cmLocalNinjaGenerator : public cmLocalGenerator
 {
 public:
-  cmLocalNinjaGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent);
+  cmLocalNinjaGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent,
+                        cmState::Snapshot snapshot);
 
   virtual ~cmLocalNinjaGenerator();
 

Source/cmLocalUnixMakefileGenerator3.cxx

@@ -80,8 +80,9 @@ static std::string cmSplitExtension(std::string const& in, std::string& base)
 
 //----------------------------------------------------------------------------
 cmLocalUnixMakefileGenerator3::
-cmLocalUnixMakefileGenerator3(cmGlobalGenerator* gg, cmLocalGenerator* parent)
-  : cmLocalGenerator(gg, parent)
+cmLocalUnixMakefileGenerator3(cmGlobalGenerator* gg, cmLocalGenerator* parent,
+                              cmState::Snapshot snapshot)
+  : cmLocalGenerator(gg, parent, snapshot)
 {
   this->MakefileVariableSize = 0;
   this->ColorMakefile = false;

Source/cmLocalUnixMakefileGenerator3.h

@@ -35,7 +35,8 @@ class cmLocalUnixMakefileGenerator3 : public cmLocalGenerator
 {
 public:
   cmLocalUnixMakefileGenerator3(cmGlobalGenerator* gg,
-                                cmLocalGenerator* parent);
+                                cmLocalGenerator* parent,
+                                cmState::Snapshot snapshot);
   virtual ~cmLocalUnixMakefileGenerator3();
 
   /**

Source/cmLocalVisualStudio10Generator.cxx

@@ -63,8 +63,9 @@ class cmVS10XMLParser : public cmXMLParser
 //----------------------------------------------------------------------------
 cmLocalVisualStudio10Generator
 ::cmLocalVisualStudio10Generator(cmGlobalGenerator* gg,
-                                 cmLocalGenerator* parent):
-  cmLocalVisualStudio7Generator(gg, parent)
+                                 cmLocalGenerator* parent,
+                                 cmState::Snapshot snapshot):
+  cmLocalVisualStudio7Generator(gg, parent, snapshot)
 {
 }
 

Source/cmLocalVisualStudio10Generator.h

@@ -26,7 +26,8 @@ class cmLocalVisualStudio10Generator : public cmLocalVisualStudio7Generator
 public:
   ///! Set cache only and recurse to false by default.
   cmLocalVisualStudio10Generator(cmGlobalGenerator* gg,
-                                 cmLocalGenerator* parent);
+                                 cmLocalGenerator* parent,
+                                 cmState::Snapshot snapshot);
 
   virtual ~cmLocalVisualStudio10Generator();
 

Source/cmLocalVisualStudio6Generator.cxx

@@ -25,8 +25,9 @@
 
 cmLocalVisualStudio6Generator
 ::cmLocalVisualStudio6Generator(cmGlobalGenerator* gg,
-                                cmLocalGenerator* parent):
-  cmLocalVisualStudioGenerator(gg, parent)
+                                cmLocalGenerator* parent,
+                                cmState::Snapshot snapshot):
+  cmLocalVisualStudioGenerator(gg, parent, snapshot)
 {
 }
 

Source/cmLocalVisualStudio6Generator.h

@@ -30,7 +30,8 @@ class cmLocalVisualStudio6Generator : public cmLocalVisualStudioGenerator
 public:
   ///! Set cache only and recurse to false by default.
   cmLocalVisualStudio6Generator(cmGlobalGenerator* gg,
-                                cmLocalGenerator* parent);
+                                cmLocalGenerator* parent,
+                                cmState::Snapshot snapshot);
 
   virtual ~cmLocalVisualStudio6Generator();
 

Source/cmLocalVisualStudio7Generator.cxx

@@ -56,8 +56,9 @@ static void cmConvertToWindowsSlash(std::string& s)
 //----------------------------------------------------------------------------
 cmLocalVisualStudio7Generator
 ::cmLocalVisualStudio7Generator(cmGlobalGenerator* gg,
-                                cmLocalGenerator* parent):
-  cmLocalVisualStudioGenerator(gg, parent)
+                                cmLocalGenerator* parent,
+                                cmState::Snapshot snapshot):
+  cmLocalVisualStudioGenerator(gg, parent, snapshot)
 {
   this->Internal = new cmLocalVisualStudio7GeneratorInternals(this);
 }

Source/cmLocalVisualStudio7Generator.h

@@ -36,7 +36,8 @@ class cmLocalVisualStudio7Generator : public cmLocalVisualStudioGenerator
 public:
   ///! Set cache only and recurse to false by default.
   cmLocalVisualStudio7Generator(cmGlobalGenerator* gg,
-                                cmLocalGenerator* parent);
+                                cmLocalGenerator* parent,
+                                cmState::Snapshot snapshot);
 
   virtual ~cmLocalVisualStudio7Generator();
 

Source/cmLocalVisualStudioGenerator.cxx

@@ -20,8 +20,9 @@
 //----------------------------------------------------------------------------
 cmLocalVisualStudioGenerator
 ::cmLocalVisualStudioGenerator(cmGlobalGenerator* gg,
-                               cmLocalGenerator* parent)
-  : cmLocalGenerator(gg, parent)
+                               cmLocalGenerator* parent,
+                               cmState::Snapshot snapshot)
+  : cmLocalGenerator(gg, parent, snapshot)
 {
 }
 

Source/cmLocalVisualStudioGenerator.h

@@ -32,7 +32,8 @@ class cmLocalVisualStudioGenerator : public cmLocalGenerator
 {
 public:
   cmLocalVisualStudioGenerator(cmGlobalGenerator* gg,
-                               cmLocalGenerator* parent);
+                               cmLocalGenerator* parent,
+                               cmState::Snapshot snapshot);
   virtual ~cmLocalVisualStudioGenerator();
 
   /** Construct a script from the given list of command lines.  */

Source/cmLocalXCodeGenerator.cxx

@@ -16,8 +16,9 @@
 
 //----------------------------------------------------------------------------
 cmLocalXCodeGenerator::cmLocalXCodeGenerator(cmGlobalGenerator* gg,
-                                             cmLocalGenerator* parent)
-  : cmLocalGenerator(gg, parent)
+                                             cmLocalGenerator* parent,
+                                             cmState::Snapshot snapshot)
+  : cmLocalGenerator(gg, parent, snapshot)
 {
   // the global generator does this, so do not
   // put these flags into the language flags

Source/cmLocalXCodeGenerator.h

@@ -24,7 +24,8 @@ class cmLocalXCodeGenerator : public cmLocalGenerator
 {
 public:
   ///! Set cache only and recurse to false by default.
-  cmLocalXCodeGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent);
+  cmLocalXCodeGenerator(cmGlobalGenerator* gg, cmLocalGenerator* parent,
+                        cmState::Snapshot snapshot);
 
   virtual ~cmLocalXCodeGenerator();
   virtual std::string GetTargetDirectory(cmTarget const& target) const;

Source/cmMakefile.cxx

@@ -1625,9 +1625,12 @@ void cmMakefile::AddSubDirectory(const std::string& srcPath,
     return;
     }
 
+  cmState::Snapshot newSnapshot = this->GetState()
+      ->CreateSnapshot(this->StateSnapshot);
+
   // create a new local generator and set its parent
   cmLocalGenerator *lg2 = this->GetGlobalGenerator()
-        ->MakeLocalGenerator(this->LocalGenerator);
+        ->MakeLocalGenerator(newSnapshot, this->LocalGenerator);
   this->GetGlobalGenerator()->AddLocalGenerator(lg2);
 
   // set the subdirs start dirs

Source/cmState.cxx

@@ -661,6 +661,10 @@ void cmState::Snapshot::ComputeRelativePathTopBinary()
 
 cmState::Snapshot cmState::CreateSnapshot(Snapshot originSnapshot)
 {
+  if (!originSnapshot.IsValid())
+    {
+    originSnapshot.State = this;
+    }
   PositionType pos = this->ParentPositions.size();
   this->ParentPositions.push_back(originSnapshot.Position);
   this->Locations.resize(this->Locations.size() + 1);