Add variable 'CMAKE_INTERPROCEDURAL_OPTIMIZATION'

Help/manual/cmake-variables.7.rst

@@ -285,6 +285,7 @@ Variables that Control the Build
    /variable/CMAKE_INSTALL_NAME_DIR
    /variable/CMAKE_INSTALL_RPATH
    /variable/CMAKE_INSTALL_RPATH_USE_LINK_PATH
+   /variable/CMAKE_INTERPROCEDURAL_OPTIMIZATION
    /variable/CMAKE_IOS_INSTALL_COMBINED
    /variable/CMAKE_LANG_CLANG_TIDY
    /variable/CMAKE_LANG_COMPILER_LAUNCHER

Help/prop_tgt/INTERPROCEDURAL_OPTIMIZATION.rst

@@ -5,3 +5,7 @@ Enable interprocedural optimization for a target.
 
 If set to true, enables interprocedural optimizations if they are
 known to be supported by the compiler.
+
+This property is initialized by the
+:variable:`CMAKE_INTERPROCEDURAL_OPTIMIZATION` variable if it is set when a
+target is created.

Help/release/dev/CMAKE_INTERPROCEDURAL_OPTIMIZATION.rst

@@ -0,0 +1,6 @@
+CMAKE_INTERPROCEDURAL_OPTIMIZATION
+----------------------------------
+
+* A :variable:`CMAKE_INTERPROCEDURAL_OPTIMIZATION` variable was added to
+  initialize the :prop_tgt:`INTERPROCEDURAL_OPTIMIZATION` property on all
+  targets.

Help/variable/CMAKE_INTERPROCEDURAL_OPTIMIZATION.rst

@@ -0,0 +1,8 @@
+CMAKE_INTERPROCEDURAL_OPTIMIZATION
+----------------------------------
+
+Default value for :prop_tgt:`INTERPROCEDURAL_OPTIMIZATION` of targets.
+
+This variable is used to initialize the :prop_tgt:`INTERPROCEDURAL_OPTIMIZATION`
+property on all the targets.  See that target property for additional
+information.

Source/cmTarget.cxx

@@ -230,6 +230,7 @@ cmTarget::cmTarget(std::string const& name, cmStateEnums::TargetType type,
     this->SetPropertyDefault("INSTALL_NAME_DIR", CM_NULLPTR);
     this->SetPropertyDefault("INSTALL_RPATH", "");
     this->SetPropertyDefault("INSTALL_RPATH_USE_LINK_PATH", "OFF");
+    this->SetPropertyDefault("INTERPROCEDURAL_OPTIMIZATION", CM_NULLPTR);
     this->SetPropertyDefault("SKIP_BUILD_RPATH", "OFF");
     this->SetPropertyDefault("BUILD_WITH_INSTALL_RPATH", "OFF");
     this->SetPropertyDefault("ARCHIVE_OUTPUT_DIRECTORY", CM_NULLPTR);