diff --git a/Source/cmFileCommand.cxx b/Source/cmFileCommand.cxx
index b5215a55ba..90b943b87c 100644
--- a/Source/cmFileCommand.cxx
+++ b/Source/cmFileCommand.cxx
@@ -757,8 +757,7 @@ bool cmFileCommand::HandleGlobCommand(std::vector<std::string> const& args,
     }
   }
 
-  std::ostringstream outputStream;
-  bool first = true;
+  std::vector<std::string> files;
   bool warnFollowedSymlinks = false;
   while (i != args.end()) {
     if (*i == "LIST_DIRECTORIES") {
@@ -848,15 +847,8 @@ bool cmFileCommand::HandleGlobCommand(std::vector<std::string> const& args,
         warnFollowedSymlinks = true;
       }
 
-      std::vector<std::string>& files = g.GetFiles();
-      std::sort(files.begin(), files.end());
-      for (std::string const& file : files) {
-        if (!first) {
-          outputStream << ";";
-        }
-        outputStream << file;
-        first = false;
-      }
+      std::vector<std::string>& foundFiles = g.GetFiles();
+      files.insert(files.end(), foundFiles.begin(), foundFiles.end());
       ++i;
     }
   }
@@ -880,7 +872,10 @@ bool cmFileCommand::HandleGlobCommand(std::vector<std::string> const& args,
       }
       break;
   }
-  this->Makefile->AddDefinition(variable, outputStream.str().c_str());
+
+  std::sort(files.begin(), files.end());
+  files.erase(std::unique(files.begin(), files.end()), files.end());
+  this->Makefile->AddDefinition(variable, cmJoin(files, ";").c_str());
   return true;
 }
 
diff --git a/Tests/RunCMake/file/GLOB-sort-dedup-stderr.txt b/Tests/RunCMake/file/GLOB-sort-dedup-stderr.txt
new file mode 100644
index 0000000000..d2565e4a95
--- /dev/null
+++ b/Tests/RunCMake/file/GLOB-sort-dedup-stderr.txt
@@ -0,0 +1,2 @@
+content: 7[ ]
+1aAb/\.hide;1aAb/1\.log;1aAb/1\.txt;1aAb/xkcd\.txt;a/1\.log;a/1\.txt;a/boot\.ini
diff --git a/Tests/RunCMake/file/GLOB-sort-dedup.cmake b/Tests/RunCMake/file/GLOB-sort-dedup.cmake
new file mode 100644
index 0000000000..1e1c5797f0
--- /dev/null
+++ b/Tests/RunCMake/file/GLOB-sort-dedup.cmake
@@ -0,0 +1,21 @@
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/test/a")
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/test/1aAb")
+
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/a/1.log" "")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/a/1.txt" "")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/a/boot.ini" "")
+
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/1aAb/.hide" "")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/1aAb/1.txt" "")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/1aAb/1.log" "")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/test/1aAb/xkcd.txt" "")
+
+file(GLOB CONTENT_LIST
+  LIST_DIRECTORIES false
+  RELATIVE "${CMAKE_CURRENT_BINARY_DIR}/test"
+  "${CMAKE_CURRENT_BINARY_DIR}/test/a/*"
+  "${CMAKE_CURRENT_BINARY_DIR}/test/*/*"
+  )
+list(LENGTH CONTENT_LIST CONTENT_COUNT)
+message("content: ${CONTENT_COUNT} ")
+message("${CONTENT_LIST}")
diff --git a/Tests/RunCMake/file/RunCMakeTest.cmake b/Tests/RunCMake/file/RunCMakeTest.cmake
index 27305d08f6..4aab32d48a 100644
--- a/Tests/RunCMake/file/RunCMakeTest.cmake
+++ b/Tests/RunCMake/file/RunCMakeTest.cmake
@@ -38,6 +38,7 @@ run_cmake(GLOB_RECURSE)
 run_cmake(GLOB_RECURSE-noexp-FOLLOW_SYMLINKS)
 
 # tests are valid both for GLOB and GLOB_RECURSE
+run_cmake(GLOB-sort-dedup)
 run_cmake(GLOB-error-FOLLOW_SYMLINKS)
 run_cmake(GLOB-error-LIST_DIRECTORIES-not-boolean)
 run_cmake(GLOB-error-LIST_DIRECTORIES-no-arg)