Allow OBJECT libraries to be installed, exported, and imported

Teach install() and export() to handle the actual object files.
Disallow this on Xcode with multiple architectures because it
still cannot be cleanly supported there.

Co-Author: Brad King <brad.king@kitware.com>

6 files changed, 42 insertions, 1 deletions

diff --git a/Tests/ExportImport/Export/CMakeLists.txt b/Tests/ExportImport/Export/CMakeLists.txt
index f504c7b..eeae3f0 100644
--- a/Tests/ExportImport/Export/CMakeLists.txt
+++ b/Tests/ExportImport/Export/CMakeLists.txt
@@ -79,6 +79,15 @@ set_property(TARGET testLib7 PROPERTY OUTPUT_NAME_DEBUG testLib7D-$<CONFIG>)
 set_property(TARGET testLib7 PROPERTY OUTPUT_NAME_RELEASE testLib7R-$<CONFIG>)
 set_property(TARGET testLib7 PROPERTY OUTPUT_NAME testLib7-$<CONFIG>)
 
+# Test exporting OBJECT targets
+add_library(testLib8 OBJECT testLib8A.c testLib8B.c sub/testLib8C.c)
+
+if(NOT CMAKE_GENERATOR STREQUAL "Xcode" OR NOT CMAKE_OSX_ARCHITECTURES MATCHES "[;$]")
+  set(maybe_testLib8 testLib8)
+else()
+  set(maybe_testLib8 "")
+endif()
+
 # Test using the target_link_libraries command to set the
 # LINK_INTERFACE_LIBRARIES* properties.  We construct two libraries
 # providing the same two symbols.  In each library one of the symbols
@@ -474,7 +483,7 @@ install(
   TARGETS
   testExe1 testLib1 testLib2 testExe2 testLib3 testLib4 testExe3 testExe4
   testExe2lib testLib4lib testLib4libdbg testLib4libopt
-  testLib6 testLib7
+  testLib6 testLib7 ${maybe_testLib8}
   testLibCycleA testLibCycleB
   testLibNoSONAME
   cmp0022NEW cmp0022OLD
@@ -483,6 +492,7 @@ install(
   RUNTIME DESTINATION $<1:bin>
   LIBRARY DESTINATION $<1:lib> NAMELINK_SKIP
   ARCHIVE DESTINATION $<1:lib>
+  OBJECTS DESTINATION $<1:lib>
   FRAMEWORK DESTINATION Frameworks
   BUNDLE DESTINATION Applications
   )
@@ -535,6 +545,7 @@ export(TARGETS testExe1 testLib1 testLib2 testLib3
   FILE ExportBuildTree.cmake
   )
 export(TARGETS testExe2 testLib4 testLib5 testLib6 testLib7 testExe3 testExe4 testExe2lib
+  ${maybe_testLib8}
   testLib4lib testLib4libdbg testLib4libopt
   testLibCycleA testLibCycleB
   testLibNoSONAME
diff --git a/Tests/ExportImport/Export/sub/testLib8C.c b/Tests/ExportImport/Export/sub/testLib8C.c
new file mode 100644
index 0000000..a5568c7
--- /dev/null
+++ b/Tests/ExportImport/Export/sub/testLib8C.c
@@ -0,0 +1,4 @@
+int testLib8C(void)
+{
+  return 0;
+}
diff --git a/Tests/ExportImport/Export/testLib8A.c b/Tests/ExportImport/Export/testLib8A.c
new file mode 100644
index 0000000..c64655a
--- /dev/null
+++ b/Tests/ExportImport/Export/testLib8A.c
@@ -0,0 +1,4 @@
+int testLib8A(void)
+{
+  return 0;
+}
diff --git a/Tests/ExportImport/Export/testLib8B.c b/Tests/ExportImport/Export/testLib8B.c
new file mode 100644
index 0000000..1be6c9c
--- /dev/null
+++ b/Tests/ExportImport/Export/testLib8B.c
@@ -0,0 +1,4 @@
+int testLib8B(void)
+{
+  return 0;
+}
diff --git a/Tests/ExportImport/Import/A/CMakeLists.txt b/Tests/ExportImport/Import/A/CMakeLists.txt
index 5ce9628..01960ea 100644
--- a/Tests/ExportImport/Import/A/CMakeLists.txt
+++ b/Tests/ExportImport/Import/A/CMakeLists.txt
@@ -228,6 +228,16 @@ target_link_libraries(imp_lib1 exp_testLib2)
 add_library(imp_lib1b STATIC imp_lib1.c)
 target_link_libraries(imp_lib1b bld_testLib2)
 
+if(NOT CMAKE_GENERATOR STREQUAL "Xcode" OR NOT CMAKE_OSX_ARCHITECTURES MATCHES "[;$]")
+  # Create a executable that is using objects imported from the install tree
+  add_executable(imp_testLib8 imp_testLib8.c $<TARGET_OBJECTS:exp_testLib8>)
+
+  if(NOT CMAKE_GENERATOR STREQUAL "Xcode" OR NOT XCODE_VERSION VERSION_LESS 5)
+    # Create a executable that is using objects imported from the build tree
+    add_executable(imp_testLib8b imp_testLib8.c $<TARGET_OBJECTS:bld_testLib8>)
+  endif()
+endif()
+
 #-----------------------------------------------------------------------------
 # Test that handling imported targets, including transitive dependencies,
 # works in CheckFunctionExists (...and hopefully all other try_compile() checks
diff --git a/Tests/ExportImport/Import/A/imp_testLib8.c b/Tests/ExportImport/Import/A/imp_testLib8.c
new file mode 100644
index 0000000..2749b17
--- /dev/null
+++ b/Tests/ExportImport/Import/A/imp_testLib8.c
@@ -0,0 +1,8 @@
+
+int testLib8A(void);
+int testLib8B(void);
+
+int main()
+{
+  return (testLib8A() + testLib8B());
+}