Merge topic 'autogen-predefs'

6bbc1e77 Autogen: Add release notes for (CMAKE_)AUTOMOC_COMPILER_PREDEFINES
75c98b5e Autogen: Doc: Add documentation for (CMAKE_)AUTOMOC_COMPILER_PREDEFINES
1d7f099d Autogen: Add (CMAKE_)AUTOMOC_COMPILER_PREDEFINES

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !1328

10 files changed, 67 insertions, 5 deletions

diff --git a/Help/manual/cmake-properties.7.rst b/Help/manual/cmake-properties.7.rst
index 0adfff6..dd59a00 100644
--- a/Help/manual/cmake-properties.7.rst
+++ b/Help/manual/cmake-properties.7.rst
@@ -122,6 +122,7 @@ Properties on Targets
    /prop_tgt/ARCHIVE_OUTPUT_NAME
    /prop_tgt/AUTOGEN_BUILD_DIR
    /prop_tgt/AUTOGEN_TARGET_DEPENDS
+   /prop_tgt/AUTOMOC_COMPILER_PREDEFINES
    /prop_tgt/AUTOMOC_DEPEND_FILTERS
    /prop_tgt/AUTOMOC_MACRO_NAMES
    /prop_tgt/AUTOMOC_MOC_OPTIONS
diff --git a/Help/manual/cmake-variables.7.rst b/Help/manual/cmake-variables.7.rst
index cba81e5..66d3049 100644
--- a/Help/manual/cmake-variables.7.rst
+++ b/Help/manual/cmake-variables.7.rst
@@ -270,6 +270,7 @@ Variables that Control the Build
    /variable/CMAKE_ARCHIVE_OUTPUT_DIRECTORY
    /variable/CMAKE_ARCHIVE_OUTPUT_DIRECTORY_CONFIG
    /variable/CMAKE_AUTOMOC
+   /variable/CMAKE_AUTOMOC_COMPILER_PREDEFINES
    /variable/CMAKE_AUTOMOC_DEPEND_FILTERS
    /variable/CMAKE_AUTOMOC_MACRO_NAMES
    /variable/CMAKE_AUTOMOC_MOC_OPTIONS
@@ -398,6 +399,7 @@ Variables for Languages
    /variable/CMAKE_LANG_COMPILER_LOADED
    /variable/CMAKE_LANG_COMPILER_TARGET
    /variable/CMAKE_LANG_COMPILER_VERSION
+   /variable/CMAKE_LANG_COMPILER_PREDEFINES_COMMAND
    /variable/CMAKE_LANG_COMPILE_OBJECT
    /variable/CMAKE_LANG_CREATE_SHARED_LIBRARY
    /variable/CMAKE_LANG_CREATE_SHARED_MODULE
diff --git a/Help/prop_tgt/AUTOMOC.rst b/Help/prop_tgt/AUTOMOC.rst
index 641ac09..9e5261f 100644
--- a/Help/prop_tgt/AUTOMOC.rst
+++ b/Help/prop_tgt/AUTOMOC.rst
@@ -76,6 +76,9 @@ Additional macro names to search for can be added to :prop_tgt:`AUTOMOC_MACRO_NA
 Additional ``moc`` dependency file names can be extracted from source code
 by using :prop_tgt:`AUTOMOC_DEPEND_FILTERS`.
 
+Compiler pre definitions for ``moc`` are written to a ``moc_predefs.h`` file
+which is controlled by :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES`.
+
 Source C++ files can be excluded from :prop_tgt:`AUTOMOC` processing by
 enabling :prop_sf:`SKIP_AUTOMOC` or the broader :prop_sf:`SKIP_AUTOGEN`.
 
diff --git a/Help/prop_tgt/AUTOMOC_COMPILER_PREDEFINES.rst b/Help/prop_tgt/AUTOMOC_COMPILER_PREDEFINES.rst
new file mode 100644
index 0000000..57a647f
--- /dev/null
+++ b/Help/prop_tgt/AUTOMOC_COMPILER_PREDEFINES.rst
@@ -0,0 +1,24 @@
+AUTOMOC_COMPILER_PREDEFINES
+---------------------------
+
+Boolean value used by :prop_tgt:`AUTOMOC` to determine if the
+compiler pre definitions file ``moc_predefs.h`` should be generated.
+
+CMake generates a ``moc_predefs.h`` file with compiler pre definitions
+from the output of the command defined in
+:variable:`CMAKE_CXX_COMPILER_PREDEFINES_COMMAND <CMAKE_<LANG>_COMPILER_PREDEFINES_COMMAND>`
+when
+
+- :prop_tgt:`AUTOMOC` is enabled,
+- :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES` is enabled,
+- :variable:`CMAKE_CXX_COMPILER_PREDEFINES_COMMAND <CMAKE_<LANG>_COMPILER_PREDEFINES_COMMAND>` isn't empty and
+- the Qt version is greater or equal 5.8.
+
+The ``moc_predefs.h`` file, which is generated in :prop_tgt:`AUTOGEN_BUILD_DIR`,
+is passed to ``moc`` as the argument to the ``--include`` option.
+
+By default :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES` is initialized from
+:variable:`CMAKE_AUTOMOC_COMPILER_PREDEFINES`, which is ON by default.
+
+See the :manual:`cmake-qt(7)` manual for more information on using CMake
+with Qt.
diff --git a/Help/release/dev/autogen-predefs.rst b/Help/release/dev/autogen-predefs.rst
new file mode 100644
index 0000000..c390e2a
--- /dev/null
+++ b/Help/release/dev/autogen-predefs.rst
@@ -0,0 +1,11 @@
+autogen-predefs
+---------------
+
+* When using :prop_tgt:`AUTOMOC`, the new variable
+  :variable:`CMAKE_AUTOMOC_COMPILER_PREDEFINES` allows to default
+  enable or disable the generation of the compiler pre definitions file
+  ``moc_predefs.h``.
+
+* When using :prop_tgt:`AUTOMOC`, the new boolean target property
+  :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES` allows to enable or disable the
+  generation of the compiler pre definitions file ``moc_predefs.h``.
diff --git a/Help/variable/CMAKE_AUTOMOC_COMPILER_PREDEFINES.rst b/Help/variable/CMAKE_AUTOMOC_COMPILER_PREDEFINES.rst
new file mode 100644
index 0000000..7e1c53d
--- /dev/null
+++ b/Help/variable/CMAKE_AUTOMOC_COMPILER_PREDEFINES.rst
@@ -0,0 +1,8 @@
+CMAKE_AUTOMOC_COMPILER_PREDEFINES
+---------------------------------
+
+This variable is used to initialize the :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES`
+property on all the targets. See that target property for additional
+information.
+
+By default it is ON.
diff --git a/Help/variable/CMAKE_LANG_COMPILER_PREDEFINES_COMMAND.rst b/Help/variable/CMAKE_LANG_COMPILER_PREDEFINES_COMMAND.rst
new file mode 100644
index 0000000..e050f43
--- /dev/null
+++ b/Help/variable/CMAKE_LANG_COMPILER_PREDEFINES_COMMAND.rst
@@ -0,0 +1,8 @@
+CMAKE_<LANG>_COMPILER_PREDEFINES_COMMAND
+----------------------------------------
+
+Command that outputs the compiler pre definitions.
+
+See :prop_tgt:`AUTOMOC` which uses
+:variable:`CMAKE_CXX_COMPILER_PREDEFINES_COMMAND <CMAKE_<LANG>_COMPILER_PREDEFINES_COMMAND>`
+to generate the :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES`.
diff --git a/Modules/CMakeGenericSystem.cmake b/Modules/CMakeGenericSystem.cmake
index 3951b2c..324a279 100644
--- a/Modules/CMakeGenericSystem.cmake
+++ b/Modules/CMakeGenericSystem.cmake
@@ -23,6 +23,7 @@ set(CMAKE_DL_LIBS "dl")
 
 set(CMAKE_FIND_LIBRARY_PREFIXES "lib")
 set(CMAKE_FIND_LIBRARY_SUFFIXES ".so" ".a")
+set(CMAKE_AUTOMOC_COMPILER_PREDEFINES ON)
 set(CMAKE_AUTOMOC_MACRO_NAMES "Q_OBJECT" "Q_GADGET" "Q_NAMESPACE")
 
 # basically all general purpose OSs support shared libs
diff --git a/Source/cmQtAutoGeneratorInitializer.cxx b/Source/cmQtAutoGeneratorInitializer.cxx
index c6f0a51..217865b 100644
--- a/Source/cmQtAutoGeneratorInitializer.cxx
+++ b/Source/cmQtAutoGeneratorInitializer.cxx
@@ -363,11 +363,14 @@ static void SetupAutoTargetMoc(cmQtAutoGenDigest const& digest,
   AddDefinitionEscaped(makefile, "_moc_depend_filters",
                        GetSafeProperty(target, "AUTOMOC_DEPEND_FILTERS"));
 
-  if (QtVersionGreaterOrEqual(digest.QtVersionMajor, digest.QtVersionMinor, 5,
-                              8)) {
-    AddDefinitionEscaped(
-      makefile, "_moc_predefs_cmd",
-      makefile->GetSafeDefinition("CMAKE_CXX_COMPILER_PREDEFINES_COMMAND"));
+  // Compiler predefines
+  if (target->GetPropertyAsBool("AUTOMOC_COMPILER_PREDEFINES")) {
+    if (QtVersionGreaterOrEqual(digest.QtVersionMajor, digest.QtVersionMinor,
+                                5, 8)) {
+      AddDefinitionEscaped(
+        makefile, "_moc_predefs_cmd",
+        makefile->GetSafeDefinition("CMAKE_CXX_COMPILER_PREDEFINES_COMMAND"));
+    }
   }
   // Moc includes and compile definitions
   {
diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index 49b0664..7a3cc76 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -244,6 +244,7 @@ cmTarget::cmTarget(std::string const& name, cmStateEnums::TargetType type,
     this->SetPropertyDefault("AUTOMOC", nullptr);
     this->SetPropertyDefault("AUTOUIC", nullptr);
     this->SetPropertyDefault("AUTORCC", nullptr);
+    this->SetPropertyDefault("AUTOMOC_COMPILER_PREDEFINES", nullptr);
     this->SetPropertyDefault("AUTOMOC_DEPEND_FILTERS", nullptr);
     this->SetPropertyDefault("AUTOMOC_MACRO_NAMES", nullptr);
     this->SetPropertyDefault("AUTOMOC_MOC_OPTIONS", nullptr);