Merge branch 'object-library' into xcode-object-library

Source/cmAddLibraryCommand.h

@@ -112,6 +112,26 @@ public:
       "(and its per-configuration version IMPORTED_LOCATION_<CONFIG>) "
       "which specifies the location of the main library file on disk.  "
       "See documentation of the IMPORTED_* properties for more information."
+      "\n"
+      "The signature\n"
+      "  add_library(<name> OBJECT <src>...)\n"
+      "creates a special \"object library\" target.  "
+      "An object library compiles source files but does not archive or link "
+      "their object files into a library.  "
+      "Instead other targets created by add_library or add_executable may "
+      "reference the objects using an expression of the form "
+      "$<TARGET_OBJECTS:objlib> as a source, where \"objlib\" is the "
+      "object library name.  "
+      "For example:\n"
+      "  add_library(... $<TARGET_OBJECTS:objlib> ...)\n"
+      "  add_executable(... $<TARGET_OBJECTS:objlib> ...)\n"
+      "will include objlib's object files in a library and an executable "
+      "along with those compiled from their own sources.  "
+      "Object libraries may contain only sources (and headers) that compile "
+      "to object files.  "
+      "They may contain custom commands generating such sources, but not "
+      "PRE_BUILD, PRE_LINK, or POST_BUILD commands.  "
+      "Object libraries cannot be imported, exported, installed, or linked."
       ;
     }
   

Tests/CMakeLists.txt

@@ -199,6 +199,7 @@ IF(BUILD_TESTING)
   ADD_TEST_MACRO(CxxOnly CxxOnly)
   ADD_TEST_MACRO(IPO COnly/COnly)
   ADD_TEST_MACRO(OutDir runtime/OutDir)
+  ADD_TEST_MACRO(ObjectLibrary UseCshared)
   ADD_TEST_MACRO(NewlineArgs NewlineArgs)
   ADD_TEST_MACRO(SetLang SetLang)
   ADD_TEST_MACRO(ExternalOBJ ExternalOBJ)

Tests/ObjectLibrary/A/CMakeLists.txt

+# Add -fPIC so objects can be used in shared libraries.
+# TODO: Need property for this.
+if(CMAKE_SHARED_LIBRARY_C_FLAGS)
+  set(CMAKE_C_FLAGS "${CMAKE_SHARED_LIBRARY_C_FLAGS} ${CMAKE_C_FLAGS}")
+endif()
+
+add_definitions(-DA)
+
+add_custom_command(
+  OUTPUT a1.c
+  DEPENDS a1.c.in
+  COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/a1.c.in
+                                   ${CMAKE_CURRENT_BINARY_DIR}/a1.c
+  )
+include_directories(${CMAKE_CURRENT_SOURCE_DIR})
+
+add_library(A OBJECT a1.c a2.c)

Tests/ObjectLibrary/A/a.h

+#ifndef A
+# error "A not defined"
+#endif
+#ifdef B
+# error "B must not be defined"
+#endif

Tests/ObjectLibrary/A/a1.c.in

+#include "a.h"
+int a1(void) { return 0; }

Tests/ObjectLibrary/A/a2.c

+#include "a.h"
+int a2(void) { return 0; }

Tests/ObjectLibrary/AB.def

+EXPORTS
+a1
+a2
+b1
+b2

Tests/ObjectLibrary/B/CMakeLists.txt

+if("${CMAKE_GENERATOR}" MATCHES "Visual Studio 6")
+  # VS 6 generator does not use per-target object locations.
+  set(vs6 _vs6)
+endif()
+
+# Add -fPIC so objects can be used in shared libraries.
+# TODO: Need property for this.
+if(CMAKE_SHARED_LIBRARY_C_FLAGS)
+  set(CMAKE_C_FLAGS "${CMAKE_SHARED_LIBRARY_C_FLAGS} ${CMAKE_C_FLAGS}")
+endif()
+
+add_definitions(-DB)
+add_library(B OBJECT b1.c b2.c)
+add_library(Bexport OBJECT b1${vs6}.c b2${vs6}.c)
+set_property(TARGET Bexport PROPERTY COMPILE_DEFINITIONS Bexport)

Tests/ObjectLibrary/B/b.h

+#ifdef A
+# error "A must not be defined"
+#endif
+#ifndef B
+# error "B not defined"
+#endif
+#if defined(_WIN32) && defined(Bexport)
+# define EXPORT_B __declspec(dllexport)
+#else
+# define EXPORT_B
+#endif

Tests/ObjectLibrary/B/b1.c

+#include "b.h"
+EXPORT_B int b1(void) { return 0; }

Tests/ObjectLibrary/B/b1_vs6.c

+#include "b1.c"

Tests/ObjectLibrary/B/b2.c

+#include "b.h"
+EXPORT_B int b2(void) { return 0; }

Tests/ObjectLibrary/B/b2_vs6.c

+#include "b2.c"

Tests/ObjectLibrary/CMakeLists.txt

+cmake_minimum_required(VERSION 2.8)
+project(ObjectLibrary C)
+
+add_subdirectory(A)
+add_subdirectory(B)
+
+add_library(Cstatic STATIC c.c $<TARGET_OBJECTS:A> $<TARGET_OBJECTS:B>)
+add_executable(UseCstatic main.c)
+target_link_libraries(UseCstatic Cstatic)
+
+add_library(Cshared SHARED c.c $<TARGET_OBJECTS:A> $<TARGET_OBJECTS:Bexport>)
+add_executable(UseCshared main.c)
+set_property(TARGET UseCshared PROPERTY COMPILE_DEFINITIONS SHARED_C)
+target_link_libraries(UseCshared Cshared)
+
+add_executable(UseCinternal main.c c.c $<TARGET_OBJECTS:A> $<TARGET_OBJECTS:B>)
+
+if("${CMAKE_GENERATOR}" MATCHES "^Visual Studio (6|7|7 .NET 2003)$")
+  # VS 6 and 7 generators do not add objects as sources so we need a
+  # dummy object to convince the IDE to build the targets below.
+  set(dummy dummy.obj) # In MinGW: gcc -c dummy.c -o dummy.obj
+elseif("${CMAKE_GENERATOR}" MATCHES "Xcode")
+  # Xcode does not seem to support targets without sources.
+  set(dummy dummy.c)
+endif()
+
+# Test static library without its own sources.
+add_library(ABstatic STATIC ${dummy} $<TARGET_OBJECTS:A> $<TARGET_OBJECTS:B>)
+add_executable(UseABstatic mainAB.c)
+target_link_libraries(UseABstatic ABstatic)
+
+# Test module definition file to export object library symbols in the test
+# below if the platform needs and supports it.
+set(ABshared_SRCS $<TARGET_OBJECTS:A>)
+if(CMAKE_LINK_DEF_FILE_FLAG OR NOT WIN32)
+  list(APPEND ABshared_SRCS $<TARGET_OBJECTS:B> AB.def)
+else()
+  set(NO_A NO_A)
+  list(APPEND ABshared_SRCS $<TARGET_OBJECTS:Bexport>)
+endif()
+
+# Test shared library without its own sources.
+add_library(ABshared SHARED ${dummy} ${ABshared_SRCS})
+add_executable(UseABshared mainAB.c)
+set_property(TARGET UseABshared PROPERTY COMPILE_DEFINITIONS SHARED_B ${NO_A})
+target_link_libraries(UseABshared ABshared)
+
+# Test executable without its own sources.
+add_library(ABmain OBJECT mainAB.c)
+add_executable(UseABinternal ${dummy}
+  $<TARGET_OBJECTS:ABmain> $<TARGET_OBJECTS:A> $<TARGET_OBJECTS:B>
+  )

Tests/ObjectLibrary/c.c

+#if defined(_WIN32) && defined(Cshared_EXPORTS)
+# define EXPORT_C __declspec(dllexport)
+#else
+# define EXPORT_C
+#endif
+
+extern int a1(void);
+extern int a2(void);
+extern int b1(void);
+extern int b2(void);
+EXPORT_C int c(void)
+{
+  return 0
+    + a1()
+    + a2()
+    + b1()
+    + b2()
+    ;
+}

Tests/ObjectLibrary/dummy.c

+int dummy(void) {return 0;}

Tests/ObjectLibrary/main.c

+#if defined(_WIN32) && defined(SHARED_C)
+# define IMPORT_C __declspec(dllimport)
+#else
+# define IMPORT_C
+#endif
+extern IMPORT_C int b1(void);
+extern IMPORT_C int b2(void);
+extern IMPORT_C int c(void);
+int main(void)
+{
+  return 0
+    + c()
+    + b1()
+    + b2()
+    ;
+}

Tests/ObjectLibrary/mainAB.c

+#if defined(_WIN32) && defined(SHARED_B)
+# define IMPORT_B __declspec(dllimport)
+#else
+# define IMPORT_B
+#endif
+extern IMPORT_B int b1(void);
+extern IMPORT_B int b2(void);
+#ifndef NO_A
+extern int a1(void);
+extern int a2(void);
+#endif
+int main(void)
+{
+  return 0
+#ifndef NO_A
+    + a1()
+    + a2()
+#endif
+    + b1()
+    + b2()
+    ;
+}

Tests/RunCMake/CMakeLists.txt

@@ -40,5 +40,7 @@ macro(add_RunCMake_test test)
     )
 endmacro()
 
+add_RunCMake_test(ObjectLibrary)
+
 add_RunCMake_test(build_command)
 add_RunCMake_test(find_package)