1 files changed, 41 insertions, 0 deletions
diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index 3e1436f..78db8ed 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -56,6 +56,8 @@ cmLocalGenerator::cmLocalGenerator()
   this->IsMakefileGenerator = false;
   this->RelativePathsConfigured = false;
   this->PathConversionsSetup = false;
+  this->BackwardsCompatibility = 0;
+  this->BackwardsCompatibilityFinal = false;
 }
 
 cmLocalGenerator::~cmLocalGenerator()
@@ -2860,3 +2862,42 @@ cmLocalGenerator::GetTargetObjectFileDirectories(cmTarget* ,
   cmSystemTools::Error("GetTargetObjectFileDirectories"
                        " called on cmLocalGenerator");
 }
+
+//----------------------------------------------------------------------------
+unsigned int cmLocalGenerator::GetBackwardsCompatibility()
+{
+  // The computed version may change until the project is fully
+  // configured.
+  if(!this->BackwardsCompatibilityFinal)
+    {
+    unsigned int major = 0;
+    unsigned int minor = 0;
+    unsigned int patch = 0;
+    if(const char* value
+       = this->Makefile->GetDefinition("CMAKE_BACKWARDS_COMPATIBILITY"))
+      {
+      switch(sscanf(value, "%u.%u.%u", &major, &minor, &patch))
+        {
+        case 2: patch = 0; break;
+        case 1: minor = 0; patch = 0; break;
+        default: break;
+        }
+      }
+    this->BackwardsCompatibility = CMake_VERSION_ENCODE(major, minor, patch);
+    this->BackwardsCompatibilityFinal = this->Configured;
+    }
+
+  return this->BackwardsCompatibility;
+}
+
+//----------------------------------------------------------------------------
+bool cmLocalGenerator::NeedBackwardsCompatibility(unsigned int major,
+                                                  unsigned int minor,
+                                                  unsigned int patch)
+{
+  // Compatibility is needed if CMAKE_BACKWARDS_COMPATIBILITY is set
+  // equal to or lower than the given version.
+  unsigned int actual_compat = this->GetBackwardsCompatibility();
+  return (actual_compat &&
+          actual_compat <= CMake_VERSION_ENCODE(major, minor, patch));
+}