Properties: Add CROSSCOMPILING_EMULATOR target property.

Add CROSSCOMPILING_EMULATOR target property for executables. This is used by
subsequent patches to run exectuables created for the target system when
crosscompiling. The property is initialized by the
CMAKE_CROSSCOMPILING_EMULATOR variable when defined.

Help/manual/cmake-properties.7.rst

@@ -119,6 +119,7 @@ Properties on Targets
    /prop_tgt/COMPILE_PDB_OUTPUT_DIRECTORY_CONFIG
    /prop_tgt/CONFIG_OUTPUT_NAME
    /prop_tgt/CONFIG_POSTFIX
+   /prop_tgt/CROSSCOMPILING_EMULATOR
    /prop_tgt/CXX_EXTENSIONS
    /prop_tgt/CXX_STANDARD
    /prop_tgt/CXX_STANDARD_REQUIRED

Help/manual/cmake-variables.7.rst

@@ -25,6 +25,7 @@ Variables that Provide Information
    /variable/CMAKE_CFG_INTDIR
    /variable/CMAKE_COMMAND
    /variable/CMAKE_CROSSCOMPILING
+   /variable/CMAKE_CROSSCOMPILING_EMULATOR
    /variable/CMAKE_CTEST_COMMAND
    /variable/CMAKE_CURRENT_BINARY_DIR
    /variable/CMAKE_CURRENT_LIST_DIR

Help/prop_tgt/CROSSCOMPILING_EMULATOR.rst

@@ -0,0 +1,4 @@
+CROSSCOMPILING_EMULATOR
+-----------------------
+
+Use the given emulator to run executables created when crosscompiling.

Help/variable/CMAKE_CROSSCOMPILING_EMULATOR.rst

@@ -0,0 +1,5 @@
+CMAKE_CROSSCOMPILING_EMULATOR
+-----------------------------
+
+Default value for the :prop_tgt:`CROSSCOMPILING_EMULATOR` target property of
+executables.  See that target property for additional information.

Source/cmTarget.cxx

@@ -442,6 +442,7 @@ void cmTarget::SetMakefile(cmMakefile* mf)
   if(this->TargetTypeValue == cmTarget::EXECUTABLE)
     {
     this->SetPropertyDefault("ANDROID_GUI", 0);
+    this->SetPropertyDefault("CROSSCOMPILING_EMULATOR", 0);
     }
   if(this->TargetTypeValue == cmTarget::SHARED_LIBRARY
       || this->TargetTypeValue == cmTarget::MODULE_LIBRARY)

Tests/RunCMake/CMakeLists.txt

@@ -226,3 +226,7 @@ add_RunCMake_test(COMPILE_LANGUAGE-genex)
 if(CMake_TEST_FindMatlab)
   add_RunCMake_test(FindMatlab)
 endif()
+
+add_executable(pseudo_emulator pseudo_emulator.c)
+add_RunCMake_test(CrosscompilingEmulator
+ -DPSEUDO_EMULATOR=$<TARGET_FILE:pseudo_emulator>)

Tests/RunCMake/CrosscompilingEmulator/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.1)
+project(${RunCMake_TEST} CXX)
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/CrosscompilingEmulator/CrosscompilingEmulatorProperty.cmake

@@ -0,0 +1,28 @@
+# This tests setting the CROSSCOMPILING_EMULATOR target property from the
+# CMAKE_CROSSCOMPILING_EMULATOR variable.
+
+# -DCMAKE_CROSSCOMPILING_EMULATOR=/path/to/pseudo_emulator is passed to this
+# test
+add_executable(target_with_emulator simple_src.cxx)
+get_property(emulator TARGET target_with_emulator
+             PROPERTY CROSSCOMPILING_EMULATOR)
+if(NOT "${emulator}" MATCHES "pseudo_emulator")
+  message(SEND_ERROR "Default CROSSCOMPILING_EMULATOR property not set")
+endif()
+
+set_property(TARGET target_with_emulator
+             PROPERTY CROSSCOMPILING_EMULATOR "another_emulator")
+get_property(emulator TARGET target_with_emulator
+             PROPERTY CROSSCOMPILING_EMULATOR)
+if(NOT "${emulator}" MATCHES "another_emulator")
+  message(SEND_ERROR
+    "set_property/get_property CROSSCOMPILING_EMULATOR is not consistent")
+endif()
+
+unset(CMAKE_CROSSCOMPILING_EMULATOR CACHE)
+add_executable(target_without_emulator simple_src.cxx)
+get_property(emulator TARGET target_without_emulator
+             PROPERTY CROSSCOMPILING_EMULATOR)
+if(NOT "${emulator}" STREQUAL "")
+  message(SEND_ERROR "Default CROSSCOMPILING_EMULATOR property not set to null")
+endif()

Tests/RunCMake/CrosscompilingEmulator/RunCMakeTest.cmake

@@ -0,0 +1,6 @@
+include(RunCMake)
+
+set(RunCMake_TEST_OPTIONS
+    "-DCMAKE_CROSSCOMPILING_EMULATOR=${PSEUDO_EMULATOR}")
+
+run_cmake(CrosscompilingEmulatorProperty)

Tests/RunCMake/CrosscompilingEmulator/simple_src.cxx

@@ -0,0 +1,4 @@
+int main(int, char **)
+{
+  return 0;
+}

Tests/RunCMake/pseudo_emulator.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+
+int main(int argc, char * argv[] )
+{
+ int ii;
+
+ printf("Command:");
+ for(ii = 1; ii < argc; ++ii)
+ {
+ printf(" \"%s\"", argv[ii]);
+ }
+ printf("\n");
+
+ return 42;
+}