diff --git a/Source/cmUnixMakefileGenerator.cxx b/Source/cmUnixMakefileGenerator.cxx
index 05d5a36f1..b0584df0b 100644
--- a/Source/cmUnixMakefileGenerator.cxx
+++ b/Source/cmUnixMakefileGenerator.cxx
@@ -1429,6 +1429,7 @@ void cmUnixMakefileGenerator::OutputMakeRules(std::ostream& fout)
   ctest = cmSystemTools::GetFilenamePath(ctest.c_str());
   ctest += "/";
   ctest += "ctest";
+  ctest += m_ExecutableExtension;
   if (cmSystemTools::FileExists(ctest.c_str()))
     {
     this->OutputMakeRule(fout,