diff --git a/Help/command/add_library.rst b/Help/command/add_library.rst
index 01c415a..ed8447e 100644
--- a/Help/command/add_library.rst
+++ b/Help/command/add_library.rst
@@ -64,42 +64,6 @@
 pre-processed, and you want to have the original sources reachable from
 within IDE.
 
-Imported Libraries
-^^^^^^^^^^^^^^^^^^
-
-.. code-block:: cmake
-
-  add_library(<name> <SHARED|STATIC|MODULE|OBJECT|UNKNOWN> IMPORTED
-              [GLOBAL])
-
-An :ref:`IMPORTED library target <Imported Targets>` references a library
-file located outside the project.  No rules are generated to build it, and
-the :prop_tgt:`IMPORTED` target property is ``True``.  The target name has
-scope in the directory in which it is created and below, but the ``GLOBAL``
-option extends visibility.  It may be referenced like any target built
-within the project.  ``IMPORTED`` libraries are useful for convenient
-reference from commands like :command:`target_link_libraries`.  Details
-about the imported library are specified by setting properties whose names
-begin in ``IMPORTED_`` and ``INTERFACE_``.
-
-The most important properties are:
-
-* :prop_tgt:`IMPORTED_LOCATION` (and its per-configuration
-  variant :prop_tgt:`IMPORTED_LOCATION_<CONFIG>`) which specifies the
-  location of the main library file on disk.
-* :prop_tgt:`IMPORTED_OBJECTS` (and :prop_tgt:`IMPORTED_OBJECTS_<CONFIG>`)
-  for object libraries, specifies the locations of object files on disk.
-* :prop_tgt:`PUBLIC_HEADER` files to be installed during :command:`install` invocation
-
-See documentation of the ``IMPORTED_*`` and ``INTERFACE_*`` properties
-for more information.
-
-An ``UNKNOWN`` library type is typically only used in the implementation of
-:ref:`Find Modules`.  It allows the path to an imported library (often found
-using the :command:`find_library` command) to be used without having to know
-what type of library it is.  This is especially useful on Windows where a
-static library and a DLL's import library both have the same file extension.
-
 Object Libraries
 ^^^^^^^^^^^^^^^^
 
@@ -129,6 +93,80 @@
 consider adding at least one real source file to any target that references
 ``$<TARGET_OBJECTS:objlib>``.
 
+Interface Libraries
+^^^^^^^^^^^^^^^^^^^
+
+.. code-block:: cmake
+
+  add_library(<name> INTERFACE)
+
+Creates an :ref:`Interface Library <Interface Libraries>`.
+An ``INTERFACE`` library target does not compile sources and does
+not produce a library artifact on disk.  However, it may have
+properties set on it and it may be installed and exported.
+Typically, ``INTERFACE_*`` properties are populated on an interface
+target using the commands:
+
+* :command:`set_property`,
+* :command:`target_link_libraries(INTERFACE)`,
+* :command:`target_link_options(INTERFACE)`,
+* :command:`target_include_directories(INTERFACE)`,
+* :command:`target_compile_options(INTERFACE)`,
+* :command:`target_compile_definitions(INTERFACE)`, and
+* :command:`target_sources(INTERFACE)`,
+
+and then it is used as an argument to :command:`target_link_libraries`
+like any other target.
+
+An interface library has no source files itself and is not included
+as a target in the generated buildsystem.
+
+Imported Libraries
+^^^^^^^^^^^^^^^^^^
+
+.. code-block:: cmake
+
+  add_library(<name> <type> IMPORTED [GLOBAL])
+
+Creates an :ref:`IMPORTED library target <Imported Targets>` called ``<name>``.
+No rules are generated to build it, and the :prop_tgt:`IMPORTED` target
+property is ``True``.  The target name has scope in the directory in which
+it is created and below, but the ``GLOBAL`` option extends visibility.
+It may be referenced like any target built within the project.
+``IMPORTED`` libraries are useful for convenient reference from commands
+like :command:`target_link_libraries`.  Details about the imported library
+are specified by setting properties whose names begin in ``IMPORTED_`` and
+``INTERFACE_``.
+
+The ``<type>`` must be one of:
+
+``STATIC``, ``SHARED``, ``MODULE``, ``UNKNOWN``
+  References a library file located outside the project.  The
+  :prop_tgt:`IMPORTED_LOCATION` target property (or its per-configuration
+  variant :prop_tgt:`IMPORTED_LOCATION_<CONFIG>`) specifies the
+  location of the main library file on disk.
+  Additional usage requirements may be specified in ``INTERFACE_*`` properties.
+
+  An ``UNKNOWN`` library type is typically only used in the implementation of
+  :ref:`Find Modules`.  It allows the path to an imported library (often found
+  using the :command:`find_library` command) to be used without having to know
+  what type of library it is.  This is especially useful on Windows where a
+  static library and a DLL's import library both have the same file extension.
+
+``OBJECT``
+  References a set of object files located outside the project.
+  The :prop_tgt:`IMPORTED_OBJECTS` target property (or its per-configuration
+  variant :prop_tgt:`IMPORTED_OBJECTS_<CONFIG>`) specifies the locations of
+  object files on disk.
+  Additional usage requirements may be specified in ``INTERFACE_*`` properties.
+
+``INTERFACE``
+  Does not reference any library or object files on disk, but may
+  specify usage requirements in ``INTERFACE_*`` properties.
+
+See documentation of the ``IMPORTED_*`` and ``INTERFACE_*`` properties
+for more information.
+
 Alias Libraries
 ^^^^^^^^^^^^^^^
 
@@ -153,35 +191,3 @@
 operand of :command:`set_property`, :command:`set_target_properties`,
 :command:`target_link_libraries` etc.  An ``ALIAS`` target may not be
 installed or exported.
-
-Interface Libraries
-^^^^^^^^^^^^^^^^^^^
-
-.. code-block:: cmake
-
-  add_library(<name> INTERFACE [IMPORTED [GLOBAL]])
-
-Creates an :ref:`Interface Library <Interface Libraries>`.  An ``INTERFACE``
-library target does not directly create build output, though it may
-have properties set on it and it may be installed, exported and
-imported. Typically the ``INTERFACE_*`` properties are populated on
-the interface target using the commands:
-
-* :command:`set_property`,
-* :command:`target_link_libraries(INTERFACE)`,
-* :command:`target_link_options(INTERFACE)`,
-* :command:`target_include_directories(INTERFACE)`,
-* :command:`target_compile_options(INTERFACE)`,
-* :command:`target_compile_definitions(INTERFACE)`, and
-* :command:`target_sources(INTERFACE)`,
-
-and then it is used as an argument to :command:`target_link_libraries`
-like any other target.
-
-An ``INTERFACE`` :ref:`Imported Target <Imported Targets>` may also be
-created with this signature.  An ``IMPORTED`` library target references a
-library defined outside the project.  The target name has scope in the
-directory in which it is created and below, but the ``GLOBAL`` option
-extends visibility.  It may be referenced like any target built within
-the project.  ``IMPORTED`` libraries are useful for convenient reference
-from commands like :command:`target_link_libraries`.
diff --git a/Help/command/target_sources.rst b/Help/command/target_sources.rst
index 856d869..653b8d7 100644
--- a/Help/command/target_sources.rst
+++ b/Help/command/target_sources.rst
@@ -11,19 +11,21 @@
     <INTERFACE|PUBLIC|PRIVATE> [items1...]
     [<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
 
-Specifies sources to use when compiling a given target.  Relative
-source file paths are interpreted as being relative to the current
+Specifies sources to use when building a target and/or its dependents.
+Relative source file paths are interpreted as being relative to the current
 source directory (i.e. :variable:`CMAKE_CURRENT_SOURCE_DIR`).  The
 named ``<target>`` must have been created by a command such as
 :command:`add_executable` or :command:`add_library` and must not be an
 :ref:`ALIAS target <Alias Targets>`.
 
 The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to
-specify the scope of the following arguments.  ``PRIVATE`` and ``PUBLIC``
+specify the scope of the items following them.  ``PRIVATE`` and ``PUBLIC``
 items will populate the :prop_tgt:`SOURCES` property of
-``<target>``.  ``PUBLIC`` and ``INTERFACE`` items will populate the
-:prop_tgt:`INTERFACE_SOURCES` property of ``<target>``.
-(:ref:`IMPORTED targets <Imported Targets>` only support ``INTERFACE`` items.)
+``<target>``, which are used when building the target itself.
+``PUBLIC`` and ``INTERFACE`` items will populate the
+:prop_tgt:`INTERFACE_SOURCES` property of ``<target>``, which are used
+when building dependents.  (:ref:`IMPORTED targets <Imported Targets>`
+only support ``INTERFACE`` items because they are not build targets.)
 The following arguments specify sources.  Repeated calls for the same
 ``<target>`` append items in the order called.
 
diff --git a/Modules/CMakeASMInformation.cmake b/Modules/CMakeASMInformation.cmake
index 03195cc..2dc1585 100644
--- a/Modules/CMakeASMInformation.cmake
+++ b/Modules/CMakeASMInformation.cmake
@@ -96,15 +96,5 @@
   set(CMAKE_EXECUTABLE_RPATH_LINK_ASM${ASM_DIALECT}_FLAG ${CMAKE_SHARED_LIBRARY_RPATH_LINK_ASM${ASM_DIALECT}_FLAG})
 endif()
 
-# to be done
-if(NOT CMAKE_ASM${ASM_DIALECT}_CREATE_SHARED_LIBRARY)
-  set(CMAKE_ASM${ASM_DIALECT}_CREATE_SHARED_LIBRARY)
-endif()
-
-if(NOT CMAKE_ASM${ASM_DIALECT}_CREATE_SHARED_MODULE)
-  set(CMAKE_ASM${ASM_DIALECT}_CREATE_SHARED_MODULE)
-endif()
-
 
 set(CMAKE_ASM${ASM_DIALECT}_INFOMATION_LOADED 1)
-
diff --git a/Modules/GoogleTestAddTests.cmake b/Modules/GoogleTestAddTests.cmake
index 5d098d9..883e1f4 100644
--- a/Modules/GoogleTestAddTests.cmake
+++ b/Modules/GoogleTestAddTests.cmake
@@ -44,8 +44,8 @@
   cmake_parse_arguments(
     ""
     ""
-    "NO_PRETTY_TYPES;NO_PRETTY_VALUES;TEST_EXECUTABLE;TEST_EXECUTOR;TEST_WORKING_DIR;TEST_PREFIX;TEST_SUFFIX;TEST_LIST;CTEST_FILE;TEST_DISCOVERY_TIMEOUT;TEST_XML_OUTPUT_DIR"
-    "TEST_EXTRA_ARGS;TEST_PROPERTIES"
+    "NO_PRETTY_TYPES;NO_PRETTY_VALUES;TEST_EXECUTABLE;TEST_WORKING_DIR;TEST_PREFIX;TEST_SUFFIX;TEST_LIST;CTEST_FILE;TEST_DISCOVERY_TIMEOUT;TEST_XML_OUTPUT_DIR"
+    "TEST_EXTRA_ARGS;TEST_PROPERTIES;TEST_EXECUTOR"
     ${ARGN}
   )
 
diff --git a/Source/CMakeVersion.cmake b/Source/CMakeVersion.cmake
index 65b9fae..091f97f 100644
--- a/Source/CMakeVersion.cmake
+++ b/Source/CMakeVersion.cmake
@@ -1,7 +1,7 @@
 # CMake version number components.
 set(CMake_VERSION_MAJOR 3)
 set(CMake_VERSION_MINOR 18)
-set(CMake_VERSION_PATCH 20200731)
+set(CMake_VERSION_PATCH 20200806)
 #set(CMake_VERSION_RC 0)
 set(CMake_VERSION_IS_DIRTY 0)
 
diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index 4d39312..7e35fe7 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -2613,7 +2613,7 @@
     }
     file << "      break()\n"
          << "    endif()\n";
-    file << "  else()\n"
+    file << "  elseif(NOT EXISTS \"" << from_file << "\")\n"
          << "    execute_process(COMMAND ${CMAKE_COMMAND}"
          << " -E sleep 1)\n"
          << "  endif()\n";
diff --git a/Source/cmNinjaNormalTargetGenerator.cxx b/Source/cmNinjaNormalTargetGenerator.cxx
index 1775085..bde5ee7 100644
--- a/Source/cmNinjaNormalTargetGenerator.cxx
+++ b/Source/cmNinjaNormalTargetGenerator.cxx
@@ -733,12 +733,8 @@
     static_cast<int>(cmSystemTools::CalculateCommandLineLengthLimit()) -
     globalGen->GetRuleCmdLength(this->LanguageLinkerDeviceRule(config));
 
-  std::string path = localGen.GetHomeRelativeOutputPath();
-  if (!path.empty()) {
-    path += '/';
-  }
   build.RspFile = this->ConvertToNinjaPath(
-    cmStrCat(path, "CMakeFiles/", genTarget->GetName(),
+    cmStrCat("CMakeFiles/", genTarget->GetName(),
              globalGen->IsMultiConfig() ? cmStrCat('.', config) : "", ".rsp"));
 
   // Gather order-only dependencies.
@@ -1160,12 +1156,8 @@
       globalGen->GetRuleCmdLength(linkBuild.Rule);
   }
 
-  std::string path = localGen.GetHomeRelativeOutputPath();
-  if (!path.empty()) {
-    path += '/';
-  }
   linkBuild.RspFile = this->ConvertToNinjaPath(
-    cmStrCat(path, "CMakeFiles/", gt->GetName(),
+    cmStrCat("CMakeFiles/", gt->GetName(),
              globalGen->IsMultiConfig() ? cmStrCat('.', config) : "", ".rsp"));
 
   // Gather order-only dependencies.
diff --git a/Source/cmQtAutoGenInitializer.cxx b/Source/cmQtAutoGenInitializer.cxx
index 205097d..06957b0 100644
--- a/Source/cmQtAutoGenInitializer.cxx
+++ b/Source/cmQtAutoGenInitializer.cxx
@@ -1181,11 +1181,54 @@
     if (useNinjaDepfile) {
       // Create a custom command that generates a timestamp file and
       // has a depfile assigned. The depfile is created by JobDepFilesMergeT.
+      //
+      // Also create an additional '_autogen_timestamp_deps' that the custom
+      // command will depend on. It will have no sources or commands to
+      // execute, but it will have dependencies that would originally be
+      // assigned to the pre-Qt 5.15 'autogen' target. These dependencies will
+      // serve as a list of order-only dependencies for the custom command,
+      // without forcing the custom command to re-execute.
+      //
+      // The dependency tree would then look like
+      // '_autogen_timestamp_deps (order-only)' <- '/timestamp' file <-
+      // '_autogen' target.
+      const auto timestampTargetName =
+        cmStrCat(this->GenTarget->GetName(), "_autogen_timestamp_deps");
+      std::vector<std::string> timestampTargetProvides;
+      cmCustomCommandLines timestampTargetCommandLines;
 
-      // Add additional autogen target dependencies
+      // Add additional autogen target dependencies to
+      // '_autogen_timestamp_deps'.
       for (const cmTarget* t : this->AutogenTarget.DependTargets) {
         dependencies.push_back(t->GetName());
       }
+
+      cmTarget* timestampTarget = this->LocalGen->AddUtilityCommand(
+        timestampTargetName, true, this->Dir.Work.c_str(),
+        /*byproducts=*/timestampTargetProvides,
+        /*depends=*/dependencies, timestampTargetCommandLines, false, nullptr);
+      this->LocalGen->AddGeneratorTarget(
+        cm::make_unique<cmGeneratorTarget>(timestampTarget, this->LocalGen));
+
+      // Set FOLDER property on the timestamp target, so it appears in the
+      // appropriate folder in an IDE or in the file api.
+      if (!this->TargetsFolder.empty()) {
+        timestampTarget->SetProperty("FOLDER", this->TargetsFolder);
+      }
+
+      // Make '/timestamp' file depend on '_autogen_timestamp_deps' and on the
+      // moc and uic executables (whichever are enabled).
+      dependencies.clear();
+      dependencies.push_back(timestampTargetName);
+
+      if (this->Moc.ExecutableTarget != nullptr) {
+        dependencies.push_back(this->Moc.ExecutableTarget->Target->GetName());
+      }
+      if (this->Uic.ExecutableTarget != nullptr) {
+        dependencies.push_back(this->Uic.ExecutableTarget->Target->GetName());
+      }
+
+      // Create the custom command that outputs the timestamp file.
       const char timestampFileName[] = "timestamp";
       const std::string outputFile =
         cmStrCat(this->Dir.Build, "/", timestampFileName);
diff --git a/Source/cmQtAutoMocUic.cxx b/Source/cmQtAutoMocUic.cxx
index 9adcabb..f6cccfb 100644
--- a/Source/cmQtAutoMocUic.cxx
+++ b/Source/cmQtAutoMocUic.cxx
@@ -2163,7 +2163,9 @@
 void cmQtAutoMocUicT::JobDepFilesMergeT::Process()
 {
   if (Log().Verbose()) {
-    Log().Info(GenT::MOC, "Merging MOC dependencies");
+    Log().Info(GenT::MOC,
+               cmStrCat("Merging MOC dependencies into ",
+                        MessagePath(BaseConst().DepFile.c_str())));
   }
   auto processDepFile =
     [](const std::string& mocOutputFile) -> std::vector<std::string> {
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 4d2a53c..294e252 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -142,6 +142,9 @@
   if(CMAKE_Fortran_COMPILER)
     list(APPEND Ninja_ARGS -DTEST_Fortran=1)
   endif()
+  if(CMake_TEST_Qt5 AND Qt5Core_FOUND)
+    list(APPEND Ninja_ARGS -DCMake_TEST_Qt5=1 -DCMAKE_TEST_Qt5Core_Version=${Qt5Core_VERSION})
+  endif()
   add_RunCMake_test(Ninja)
   set(NinjaMultiConfig_ARGS
     -DCYGWIN=${CYGWIN}
diff --git a/Tests/RunCMake/Ninja/Qt5AutoMocDeps.cmake b/Tests/RunCMake/Ninja/Qt5AutoMocDeps.cmake
new file mode 100644
index 0000000..d69a119
--- /dev/null
+++ b/Tests/RunCMake/Ninja/Qt5AutoMocDeps.cmake
@@ -0,0 +1,9 @@
+enable_language(CXX)
+
+find_package(Qt5Core REQUIRED)
+
+set(CMAKE_AUTOMOC ON)
+
+add_library(simple_lib SHARED simple_lib.cpp)
+add_executable(app_with_qt app.cpp app_qt.cpp)
+target_link_libraries(app_with_qt PRIVATE simple_lib Qt5::Core)
diff --git a/Tests/RunCMake/Ninja/RunCMakeTest.cmake b/Tests/RunCMake/Ninja/RunCMakeTest.cmake
index 8f9c263..d43023b 100644
--- a/Tests/RunCMake/Ninja/RunCMakeTest.cmake
+++ b/Tests/RunCMake/Ninja/RunCMakeTest.cmake
@@ -138,6 +138,7 @@
     message(FATAL_ERROR
       "top ninja build failed exited with status ${ninja_result}")
   endif()
+  set(ninja_stdout "${ninja_stdout}" PARENT_SCOPE)
 endfunction(run_ninja)
 
 function (run_LooseObjectDepends)
@@ -322,3 +323,23 @@
   run_ninja("${RunCMake_TEST_BINARY_DIR}" -w dupbuild=err)
 endfunction()
 run_ChangeBuildType()
+
+function(run_Qt5AutoMocDeps)
+  if(CMake_TEST_Qt5 AND CMAKE_TEST_Qt5Core_Version VERSION_GREATER_EQUAL 5.15.0)
+    set(RunCMake_TEST_BINARY_DIR ${RunCMake_BINARY_DIR}/Qt5AutoMocDeps-build)
+    run_cmake(Qt5AutoMocDeps)
+    unset(RunCMake_TEST_OPTIONS)
+    # Build the project.
+    run_ninja("${RunCMake_TEST_BINARY_DIR}")
+    # Touch just the library source file, which shouldn't cause a rerun of AUTOMOC
+    # for app_with_qt target.
+    touch("${RunCMake_SOURCE_DIR}/simple_lib.cpp")
+    # Build and assert that AUTOMOC was not run for app_with_qt.
+    run_ninja("${RunCMake_TEST_BINARY_DIR}")
+    if(ninja_stdout MATCHES "Automatic MOC for target app_with_qt")
+        message(FATAL_ERROR
+               "AUTOMOC should not have executed for 'app_with_qt' target:\nstdout:\n${ninja_stdout}")
+    endif()
+  endif()
+endfunction()
+run_Qt5AutoMocDeps()
diff --git a/Tests/RunCMake/Ninja/app.cpp b/Tests/RunCMake/Ninja/app.cpp
new file mode 100644
index 0000000..57380e4
--- /dev/null
+++ b/Tests/RunCMake/Ninja/app.cpp
@@ -0,0 +1,6 @@
+int main(int argc, char* argv[])
+{
+  (void)argc;
+  (void)argv;
+  return 0;
+}
diff --git a/Tests/RunCMake/Ninja/app_qt.cpp b/Tests/RunCMake/Ninja/app_qt.cpp
new file mode 100644
index 0000000..302c672
--- /dev/null
+++ b/Tests/RunCMake/Ninja/app_qt.cpp
@@ -0,0 +1,11 @@
+#include <QObject>
+
+class Mango : public QObject
+{
+  Q_OBJECT
+public:
+Q_SIGNALS:
+  void eatFruit();
+};
+
+#include "app_qt.moc"
diff --git a/Tests/RunCMake/Ninja/simple_lib.cpp b/Tests/RunCMake/Ninja/simple_lib.cpp
new file mode 100644
index 0000000..cf8d689
--- /dev/null
+++ b/Tests/RunCMake/Ninja/simple_lib.cpp
@@ -0,0 +1,6 @@
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+  void dummy_symbol()
+{
+}