target_link_libraries: Add PUBLIC/PRIVATE/INTERFACE keyword signature

Add a new signature to help populate INTERFACE_LINK_LIBRARIES and
LINK_LIBRARIES cleanly in a single call.  Add policy CMP0023 to control
whether the keyword signatures can be mixed with uses of the plain
signatures on the same target.

30 files changed, 407 insertions, 19 deletions

diff --git a/Source/cmPolicies.cxx b/Source/cmPolicies.cxx
index 70c28d4a40..0ba673e404 100644
--- a/Source/cmPolicies.cxx
+++ b/Source/cmPolicies.cxx
@@ -575,6 +575,32 @@ cmPolicies::cmPolicies()
     "property for in-build targets, and ignore the old properties matching "
     "(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?.",
     2,8,11,20130516, cmPolicies::WARN);
+
+  this->DefinePolicy(
+    CMP0023, "CMP0023",
+    "Plain and keyword target_link_libraries signatures cannot be mixed.",
+    "CMake 2.8.12 introduced the target_link_libraries signature using "
+    "the PUBLIC, PRIVATE, and INTERFACE keywords to generalize the "
+    "LINK_PUBLIC and LINK_PRIVATE keywords introduced in CMake 2.8.7.  "
+    "Use of signatures with any of these keywords sets the link interface "
+    "of a target explicitly, even if empty.  "
+    "This produces confusing behavior when used in combination with the "
+    "historical behavior of the plain target_link_libraries signature.  "
+    "For example, consider the code:\n"
+    " target_link_libraries(mylib A)\n"
+    " target_link_libraries(mylib PRIVATE B)\n"
+    "After the first line the link interface has not been set explicitly "
+    "so CMake would use the link implementation, A, as the link interface.  "
+    "However, the second line sets the link interface to empty.  "
+    "In order to avoid this subtle behavior CMake now prefers to disallow "
+    "mixing the plain and keyword signatures of target_link_libraries for "
+    "a single target."
+    "\n"
+    "The OLD behavior for this policy is to allow keyword and plain "
+    "target_link_libraries signatures to be mixed.  "
+    "The NEW behavior for this policy is to not to allow mixing of the "
+    "keyword and plain signatures.",
+    2,8,11,20130724, cmPolicies::WARN);
 }
 
 cmPolicies::~cmPolicies()
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 20c953fd68..5b843a9ada 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -73,6 +73,7 @@ public:
     CMP0021, ///< Fatal error on relative paths in INCLUDE_DIRECTORIES
     /// target property
     CMP0022, ///< INTERFACE_LINK_LIBRARIES defines the link interface
+    CMP0023, ///< Disallow mixing keyword and plain tll signatures
 
     /** \brief Always the last entry.
      *
diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index 26bf9b7323..0b3b7853e0 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -2494,6 +2494,57 @@ static std::string targetNameGenex(const char *lib)
 }
 
 //----------------------------------------------------------------------------
+bool cmTarget::PushTLLCommandTrace(TLLSignature signature)
+{
+  bool ret = true;
+  if (!this->TLLCommands.empty())
+    {
+    if (this->TLLCommands.back().first != signature)
+      {
+      ret = false;
+      }
+    }
+  cmListFileBacktrace lfbt;
+  this->Makefile->GetBacktrace(lfbt);
+  this->TLLCommands.push_back(std::make_pair(signature, lfbt));
+  return ret;
+}
+
+//----------------------------------------------------------------------------
+void cmTarget::GetTllSignatureTraces(cmOStringStream &s,
+                                     TLLSignature sig) const
+{
+  std::vector<cmListFileBacktrace> sigs;
+  typedef std::vector<std::pair<TLLSignature, cmListFileBacktrace> > Container;
+  for(Container::const_iterator it = this->TLLCommands.begin();
+      it != this->TLLCommands.end(); ++it)
+    {
+    if (it->first == sig)
+      {
+      sigs.push_back(it->second);
+      }
+    }
+  if (!sigs.empty())
+    {
+    const char *sigString
+                        = (sig == cmTarget::KeywordTLLSignature ? "keyword"
+                                                                : "plain");
+    s << "The uses of the " << sigString << " signature are here:\n";
+    for(std::vector<cmListFileBacktrace>::const_iterator it = sigs.begin();
+        it != sigs.end(); ++it)
+      {
+      cmListFileBacktrace::const_iterator i = it->begin();
+      if(i != it->end())
+        {
+        cmListFileContext const& lfc = *i;
+        s << " * " << (lfc.Line? "": " in ") << lfc << std::endl;
+        ++i;
+        }
+      }
+    }
+}
+
+//----------------------------------------------------------------------------
 void cmTarget::AddLinkLibrary(cmMakefile& mf,
                               const char *target, const char* lib,
                               LinkLibraryType llt)
diff --git a/Source/cmTarget.h b/Source/cmTarget.h
index 0da0f12f80..24a71ed63f 100644
--- a/Source/cmTarget.h
+++ b/Source/cmTarget.h
@@ -190,6 +190,12 @@ public:
   void AddLinkLibrary(cmMakefile& mf,
                       const char *target, const char* lib,
                       LinkLibraryType llt);
+  enum TLLSignature {
+    KeywordTLLSignature,
+    PlainTLLSignature
+  };
+  bool PushTLLCommandTrace(TLLSignature signature);
+  void GetTllSignatureTraces(cmOStringStream &s, TLLSignature sig) const;
 
   void MergeLinkLibraries( cmMakefile& mf, const char* selfname,
                            const LinkLibraryVectorType& libs );
@@ -548,6 +554,8 @@ private:
   // directories.
   std::set<cmStdString> SystemIncludeDirectories;
 
+  std::vector<std::pair<TLLSignature, cmListFileBacktrace> > TLLCommands;
+
   /**
    * A list of direct dependencies. Use in conjunction with DependencyMap.
    */
diff --git a/Source/cmTargetLinkLibrariesCommand.cxx b/Source/cmTargetLinkLibrariesCommand.cxx
index c5f490e001..0ee9420288 100644
--- a/Source/cmTargetLinkLibrariesCommand.cxx
+++ b/Source/cmTargetLinkLibrariesCommand.cxx
@@ -116,7 +116,7 @@ bool cmTargetLinkLibrariesCommand
     {
     if(args[i] == "LINK_INTERFACE_LIBRARIES")
       {
-      this->CurrentProcessingState = ProcessingLinkInterface;
+      this->CurrentProcessingState = ProcessingPlainLinkInterface;
       if(i != 1)
         {
         this->Makefile->IssueMessage(
@@ -127,9 +127,26 @@ bool cmTargetLinkLibrariesCommand
         return true;
         }
       }
+    else if(args[i] == "INTERFACE")
+      {
+      if(i != 1
+          && this->CurrentProcessingState != ProcessingKeywordPrivateInterface
+          && this->CurrentProcessingState != ProcessingKeywordPublicInterface
+          && this->CurrentProcessingState != ProcessingKeywordLinkInterface)
+        {
+        this->Makefile->IssueMessage(
+          cmake::FATAL_ERROR,
+          "The INTERFACE option must appear as the second "
+          "argument, just after the target name."
+          );
+        return true;
+        }
+      this->CurrentProcessingState = ProcessingKeywordLinkInterface;
+      }
     else if(args[i] == "LINK_PUBLIC")
       {
-      if(i != 1 && this->CurrentProcessingState != ProcessingPrivateInterface)
+      if(i != 1
+          && this->CurrentProcessingState != ProcessingPlainPrivateInterface)
         {
         this->Makefile->IssueMessage(
           cmake::FATAL_ERROR,
@@ -138,11 +155,28 @@ bool cmTargetLinkLibrariesCommand
           );
         return true;
         }
-      this->CurrentProcessingState = ProcessingPublicInterface;
+      this->CurrentProcessingState = ProcessingPlainPublicInterface;
+      }
+    else if(args[i] == "PUBLIC")
+      {
+      if(i != 1
+          && this->CurrentProcessingState != ProcessingKeywordPrivateInterface
+          && this->CurrentProcessingState != ProcessingKeywordPublicInterface
+          && this->CurrentProcessingState != ProcessingKeywordLinkInterface)
+        {
+        this->Makefile->IssueMessage(
+          cmake::FATAL_ERROR,
+          "The PUBLIC or PRIVATE option must appear as the second "
+          "argument, just after the target name."
+          );
+        return true;
+        }
+      this->CurrentProcessingState = ProcessingKeywordPublicInterface;
       }
     else if(args[i] == "LINK_PRIVATE")
       {
-      if(i != 1 && this->CurrentProcessingState != ProcessingPublicInterface)
+      if(i != 1
+          && this->CurrentProcessingState != ProcessingPlainPublicInterface)
         {
         this->Makefile->IssueMessage(
           cmake::FATAL_ERROR,
@@ -151,7 +185,23 @@ bool cmTargetLinkLibrariesCommand
           );
         return true;
         }
-      this->CurrentProcessingState = ProcessingPrivateInterface;
+      this->CurrentProcessingState = ProcessingPlainPrivateInterface;
+      }
+    else if(args[i] == "PRIVATE")
+      {
+      if(i != 1
+          && this->CurrentProcessingState != ProcessingKeywordPrivateInterface
+          && this->CurrentProcessingState != ProcessingKeywordPublicInterface
+          && this->CurrentProcessingState != ProcessingKeywordLinkInterface)
+        {
+        this->Makefile->IssueMessage(
+          cmake::FATAL_ERROR,
+          "The PUBLIC or PRIVATE option must appear as the second "
+          "argument, just after the target name."
+          );
+        return true;
+        }
+      this->CurrentProcessingState = ProcessingKeywordPrivateInterface;
       }
     else if(args[i] == "debug")
       {
@@ -184,7 +234,10 @@ bool cmTargetLinkLibrariesCommand
       {
       // The link type was specified by the previous argument.
       haveLLT = false;
-      this->HandleLibrary(args[i].c_str(), llt);
+      if (!this->HandleLibrary(args[i].c_str(), llt))
+        {
+        return false;
+        }
       }
     else
       {
@@ -210,7 +263,10 @@ bool cmTargetLinkLibrariesCommand
           llt = cmTarget::OPTIMIZED;
           }
         }
-      this->HandleLibrary(args[i].c_str(), llt);
+      if (!this->HandleLibrary(args[i].c_str(), llt))
+        {
+        return false;
+        }
       }
     }
 
@@ -257,16 +313,69 @@ cmTargetLinkLibrariesCommand
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 cmTargetLinkLibrariesCommand::HandleLibrary(const char* lib,
                                             cmTarget::LinkLibraryType llt)
 {
+  cmTarget::TLLSignature sig =
+        (this->CurrentProcessingState == ProcessingPlainPrivateInterface
+      || this->CurrentProcessingState == ProcessingPlainPublicInterface
+      || this->CurrentProcessingState == ProcessingKeywordPrivateInterface
+      || this->CurrentProcessingState == ProcessingKeywordPublicInterface
+      || this->CurrentProcessingState == ProcessingKeywordLinkInterface)
+        ? cmTarget::KeywordTLLSignature : cmTarget::PlainTLLSignature;
+  if (!this->Target->PushTLLCommandTrace(sig))
+    {
+    const char *modal = 0;
+    cmake::MessageType messageType = cmake::AUTHOR_WARNING;
+    switch(this->Makefile->GetPolicyStatus(cmPolicies::CMP0023))
+      {
+      case cmPolicies::WARN:
+        modal = "should";
+      case cmPolicies::OLD:
+        break;
+      case cmPolicies::REQUIRED_ALWAYS:
+      case cmPolicies::REQUIRED_IF_USED:
+      case cmPolicies::NEW:
+        modal = "must";
+        messageType = cmake::FATAL_ERROR;
+      }
+
+      if(modal)
+        {
+        cmOStringStream e;
+        // If the sig is a keyword form and there is a conflict, the existing
+        // form must be the plain form.
+        const char *existingSig
+                    = (sig == cmTarget::KeywordTLLSignature ? "plain"
+                                                            : "keyword");
+        e << this->Makefile->GetPolicies()
+                              ->GetPolicyWarning(cmPolicies::CMP0023) << "\n"
+            "The " << existingSig << " signature for target_link_libraries "
+            "has already been used with the target \""
+          << this->Target->GetName() << "\".  All uses of "
+             "target_link_libraries with a target " << modal << " be either "
+             "all-keyword or all-plain.\n";
+        this->Target->GetTllSignatureTraces(e,
+                                          sig == cmTarget::KeywordTLLSignature
+                                            ? cmTarget::PlainTLLSignature
+                                            : cmTarget::KeywordTLLSignature);
+        this->Makefile->IssueMessage(messageType, e.str().c_str());
+        if(messageType == cmake::FATAL_ERROR)
+          {
+          return false;
+          }
+        }
+    }
+
   // Handle normal case first.
-  if(this->CurrentProcessingState != ProcessingLinkInterface)
+  if(this->CurrentProcessingState != ProcessingKeywordLinkInterface
+      && this->CurrentProcessingState != ProcessingPlainLinkInterface)
     {
     this->Makefile
       ->AddLinkLibraryForTarget(this->Target->GetName(), lib, llt);
-    if (this->CurrentProcessingState != ProcessingPublicInterface)
+    if (this->CurrentProcessingState != ProcessingKeywordPublicInterface
+        && this->CurrentProcessingState != ProcessingPlainPublicInterface)
       {
       if (this->Target->GetType() == cmTarget::STATIC_LIBRARY)
         {
@@ -275,8 +384,9 @@ cmTargetLinkLibrariesCommand::HandleLibrary(const char* lib,
                   this->Target->GetDebugGeneratorExpressions(lib, llt) +
                   ">").c_str());
         }
-      // Not LINK_INTERFACE_LIBRARIES or LINK_PUBLIC, do not add to interface.
-      return;
+      // Not a 'public' or 'interface' library. Do not add to interface
+      // property.
+      return true;
       }
     }
 
@@ -289,7 +399,7 @@ cmTargetLinkLibrariesCommand::HandleLibrary(const char* lib,
   if (policy22Status != cmPolicies::OLD
       && policy22Status != cmPolicies::WARN)
     {
-    return;
+    return true;
     }
 
   // Get the list of configurations considered to be DEBUG.
@@ -327,4 +437,5 @@ cmTargetLinkLibrariesCommand::HandleLibrary(const char* lib,
         }
       }
     }
+  return true;
 }
diff --git a/Source/cmTargetLinkLibrariesCommand.h b/Source/cmTargetLinkLibrariesCommand.h
index e3903434e8..f2b25433c5 100644
--- a/Source/cmTargetLinkLibrariesCommand.h
+++ b/Source/cmTargetLinkLibrariesCommand.h
@@ -113,6 +113,16 @@ public:
       "directory of the framework will also be processed as a \"usage "
       "requirement\".  This has the same effect as passing the framework "
       "directory as an include directory."
+      "  target_link_libraries(<target>\n"
+      "                      <PRIVATE|PUBLIC|INTERFACE> <lib> ...\n"
+      "                      [<PRIVATE|PUBLIC|INTERFACE> <lib> ... ] ...])\n"
+      "The PUBLIC, PRIVATE and INTERFACE keywords can be used to specify "
+      "both the link dependencies and the link interface in one command.  "
+      "Libraries and targets following PUBLIC are linked to, and are "
+      "made part of the link interface.  Libraries and targets "
+      "following PRIVATE are linked to, but are not made part of the "
+      "link interface.  Libraries following INTERFACE are appended "
+      "to the link interface and are not used for linking <target>."
       "\n"
       "  target_link_libraries(<target> LINK_INTERFACE_LIBRARIES\n"
       "                        [[debug|optimized|general] <lib>] ...)\n"
@@ -120,7 +130,8 @@ public:
       "to the INTERFACE_LINK_LIBRARIES target property instead of using them "
       "for linking.  If policy CMP0022 is not NEW, then this mode also "
       "appends libraries to the LINK_INTERFACE_LIBRARIES and its "
-      "per-configuration equivalent.  "
+      "per-configuration equivalent.  This signature "
+      "is for compatibility only. Prefer the INTERFACE mode instead.  "
       "Libraries specified as \"debug\" are wrapped in a generator "
       "expression to correspond to debug builds.  If policy CMP0022 is not "
       "NEW, the libraries are also appended to the "
@@ -139,7 +150,9 @@ public:
       "                        [<LINK_PRIVATE|LINK_PUBLIC>\n"
       "                          [[debug|optimized|general] <lib>] ...])\n"
       "The LINK_PUBLIC and LINK_PRIVATE modes can be used to specify both "
-      "the link dependencies and the link interface in one command.  "
+      "the link dependencies and the link interface in one command.  This "
+      "signature is for compatibility only. Prefer the PUBLIC or PRIVATE "
+      "keywords instead.  "
       "Libraries and targets following LINK_PUBLIC are linked to, and are "
       "made part of the INTERFACE_LINK_LIBRARIES.  If policy CMP0022 is not "
       "NEW, they are also made part of the LINK_INTERFACE_LIBRARIES.  "
@@ -185,14 +198,17 @@ private:
   cmTarget* Target;
   enum ProcessingState {
     ProcessingLinkLibraries,
-    ProcessingLinkInterface,
-    ProcessingPublicInterface,
-    ProcessingPrivateInterface
+    ProcessingPlainLinkInterface,
+    ProcessingKeywordLinkInterface,
+    ProcessingPlainPublicInterface,
+    ProcessingKeywordPublicInterface,
+    ProcessingPlainPrivateInterface,
+    ProcessingKeywordPrivateInterface
   };
 
   ProcessingState CurrentProcessingState;
 
-  void HandleLibrary(const char* lib, cmTarget::LinkLibraryType llt);
+  bool HandleLibrary(const char* lib, cmTarget::LinkLibraryType llt);
 };
 
 
diff --git a/Tests/CMakeCommands/target_link_libraries/CMakeLists.txt b/Tests/CMakeCommands/target_link_libraries/CMakeLists.txt
index 224053994f..06019e6910 100644
--- a/Tests/CMakeCommands/target_link_libraries/CMakeLists.txt
+++ b/Tests/CMakeCommands/target_link_libraries/CMakeLists.txt
@@ -124,3 +124,9 @@ add_library(libConsumer empty.cpp)
 target_link_libraries(libConsumer debug depA)
 
 add_subdirectory(cmp0022)
+
+add_executable(newsignature1 newsignature1.cpp)
+target_link_libraries(newsignature1 PRIVATE depC INTERFACE depD PUBLIC depB PRIVATE subdirlib INTERFACE INTERFACE PUBLIC)
+
+assert_property(newsignature1 INTERFACE_LINK_LIBRARIES "depD;depB")
+assert_property(newsignature1 LINK_LIBRARIES "depC;depB;subdirlib")
diff --git a/Tests/CMakeCommands/target_link_libraries/newsignature1.cpp b/Tests/CMakeCommands/target_link_libraries/newsignature1.cpp
new file mode 100644
index 0000000000..d1321a15fe
--- /dev/null
+++ b/Tests/CMakeCommands/target_link_libraries/newsignature1.cpp
@@ -0,0 +1,19 @@
+
+#include "depB.h"
+#include "depC.h"
+#include "depIfaceOnly.h"
+
+#include "subdirlib.h"
+
+int main(int, char **)
+{
+  DepA a;
+  DepB b;
+  DepC c;
+
+  DepIfaceOnly iface_only;
+
+  SubDirLibObject sd;
+
+  return a.foo() + b.foo() + c.foo() + iface_only.foo() + sd.foo();
+}
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 66ce3f12f2..12f68d7c08 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -115,3 +115,4 @@ if("${CMAKE_TEST_GENERATOR}" MATCHES "Visual Studio [^6]")
 endif()
 
 add_RunCMake_test(File_Generate)
+add_RunCMake_test(target_link_libraries)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2-result.txt b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2-result.txt
new file mode 100644
index 0000000000..d00491fd7e
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2-stderr.txt b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2-stderr.txt
new file mode 100644
index 0000000000..d27686d4b9
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2-stderr.txt
@@ -0,0 +1,16 @@
+CMake Error at CMP0023-NEW-2.cmake:11 \(target_link_libraries\):
+  Policy CMP0023 is not set: Plain and keyword target_link_libraries
+  signatures cannot be mixed.  Run "cmake --help-policy CMP0023" for policy
+  details.  Use the cmake_policy command to set the policy and suppress this
+  warning.
+
+  The plain signature for target_link_libraries has already been used with
+  the target "foo".  All uses of target_link_libraries with a target must be
+  either all-keyword or all-plain.
+
+  The uses of the plain signature are here:
+
+   \* CMP0023-NEW-2.cmake:10 \(target_link_libraries\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2.cmake b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2.cmake
new file mode 100644
index 0000000000..f8b354690c
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-2.cmake
@@ -0,0 +1,11 @@
+
+project(CMP0022-WARN)
+
+cmake_policy(SET CMP0023 NEW)
+
+add_library(foo SHARED empty_vs6_1.cpp)
+add_library(bar SHARED empty_vs6_2.cpp)
+add_library(bat SHARED empty_vs6_3.cpp)
+
+target_link_libraries(foo bar)
+target_link_libraries(foo LINK_PRIVATE bat)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-NEW-result.txt b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-result.txt
new file mode 100644
index 0000000000..d00491fd7e
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-NEW-stderr.txt b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-stderr.txt
new file mode 100644
index 0000000000..d7be0ff38a
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-NEW-stderr.txt
@@ -0,0 +1,16 @@
+CMake Error at CMP0023-NEW.cmake:11 \(target_link_libraries\):
+  Policy CMP0023 is not set: Plain and keyword target_link_libraries
+  signatures cannot be mixed.  Run "cmake --help-policy CMP0023" for policy
+  details.  Use the cmake_policy command to set the policy and suppress this
+  warning.
+
+  The plain signature for target_link_libraries has already been used with
+  the target "foo".  All uses of target_link_libraries with a target must be
+  either all-keyword or all-plain.
+
+  The uses of the plain signature are here:
+
+   \* CMP0023-NEW.cmake:10 \(target_link_libraries\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-NEW.cmake b/Tests/RunCMake/target_link_libraries/CMP0023-NEW.cmake
new file mode 100644
index 0000000000..f0aa63fbd4
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-NEW.cmake
@@ -0,0 +1,11 @@
+
+project(CMP0022-WARN)
+
+cmake_policy(SET CMP0023 NEW)
+
+add_library(foo SHARED empty_vs6_1.cpp)
+add_library(bar SHARED empty_vs6_2.cpp)
+add_library(bat SHARED empty_vs6_3.cpp)
+
+target_link_libraries(foo bar)
+target_link_libraries(foo PRIVATE bat)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-WARN-2-stderr.txt b/Tests/RunCMake/target_link_libraries/CMP0023-WARN-2-stderr.txt
new file mode 100644
index 0000000000..5147861540
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-WARN-2-stderr.txt
@@ -0,0 +1,16 @@
+CMake Warning \(dev\) at CMP0023-WARN-2.cmake:9 \(target_link_libraries\):
+  Policy CMP0023 is not set: Plain and keyword target_link_libraries
+  signatures cannot be mixed.  Run "cmake --help-policy CMP0023" for policy
+  details.  Use the cmake_policy command to set the policy and suppress this
+  warning.
+
+  The plain signature for target_link_libraries has already been used with
+  the target "foo".  All uses of target_link_libraries with a target should
+  be either all-keyword or all-plain.
+
+  The uses of the plain signature are here:
+
+   \* CMP0023-WARN-2.cmake:8 \(target_link_libraries\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-WARN-2.cmake b/Tests/RunCMake/target_link_libraries/CMP0023-WARN-2.cmake
new file mode 100644
index 0000000000..2e9cba82c3
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-WARN-2.cmake
@@ -0,0 +1,9 @@
+
+project(CMP0022-WARN)
+
+add_library(foo SHARED empty_vs6_1.cpp)
+add_library(bar SHARED empty_vs6_2.cpp)
+add_library(bat SHARED empty_vs6_3.cpp)
+
+target_link_libraries(foo bar)
+target_link_libraries(foo LINK_PRIVATE bat)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-WARN-stderr.txt b/Tests/RunCMake/target_link_libraries/CMP0023-WARN-stderr.txt
new file mode 100644
index 0000000000..a7474fac9d
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-WARN-stderr.txt
@@ -0,0 +1,16 @@
+CMake Warning \(dev\) at CMP0023-WARN.cmake:9 \(target_link_libraries\):
+  Policy CMP0023 is not set: Plain and keyword target_link_libraries
+  signatures cannot be mixed.  Run "cmake --help-policy CMP0023" for policy
+  details.  Use the cmake_policy command to set the policy and suppress this
+  warning.
+
+  The plain signature for target_link_libraries has already been used with
+  the target "foo".  All uses of target_link_libraries with a target should
+  be either all-keyword or all-plain.
+
+  The uses of the plain signature are here:
+
+   \* CMP0023-WARN.cmake:8 \(target_link_libraries\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/target_link_libraries/CMP0023-WARN.cmake b/Tests/RunCMake/target_link_libraries/CMP0023-WARN.cmake
new file mode 100644
index 0000000000..fcc8da03e9
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMP0023-WARN.cmake
@@ -0,0 +1,9 @@
+
+project(CMP0022-WARN)
+
+add_library(foo SHARED empty_vs6_1.cpp)
+add_library(bar SHARED empty_vs6_2.cpp)
+add_library(bat SHARED empty_vs6_3.cpp)
+
+target_link_libraries(foo bar)
+target_link_libraries(foo PRIVATE bat)
diff --git a/Tests/RunCMake/target_link_libraries/CMakeLists.txt b/Tests/RunCMake/target_link_libraries/CMakeLists.txt
new file mode 100644
index 0000000000..e8db6b05be
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/CMakeLists.txt
@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 2.8)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake)
diff --git a/Tests/RunCMake/target_link_libraries/MixedSignature-result.txt b/Tests/RunCMake/target_link_libraries/MixedSignature-result.txt
new file mode 100644
index 0000000000..d00491fd7e
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/MixedSignature-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/target_link_libraries/MixedSignature-stderr.txt b/Tests/RunCMake/target_link_libraries/MixedSignature-stderr.txt
new file mode 100644
index 0000000000..a0c66dbe2a
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/MixedSignature-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at MixedSignature.cmake:6 \(target_link_libraries\):
+  The PUBLIC or PRIVATE option must appear as the second argument, just after
+  the target name.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/target_link_libraries/MixedSignature.cmake b/Tests/RunCMake/target_link_libraries/MixedSignature.cmake
new file mode 100644
index 0000000000..fa70685848
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/MixedSignature.cmake
@@ -0,0 +1,6 @@
+
+add_library(foo empty_vs6_1.cpp)
+add_library(bar empty_vs6_2.cpp)
+add_library(bat empty_vs6_3.cpp)
+
+target_link_libraries(foo LINK_PUBLIC bar PRIVATE bat)
diff --git a/Tests/RunCMake/target_link_libraries/RunCMakeTest.cmake b/Tests/RunCMake/target_link_libraries/RunCMakeTest.cmake
new file mode 100644
index 0000000000..f97022e1b4
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/RunCMakeTest.cmake
@@ -0,0 +1,8 @@
+include(RunCMake)
+
+run_cmake(CMP0023-WARN)
+run_cmake(CMP0023-NEW)
+run_cmake(CMP0023-WARN-2)
+run_cmake(CMP0023-NEW-2)
+run_cmake(MixedSignature)
+run_cmake(Separate-PRIVATE-LINK_PRIVATE-uses)
diff --git a/Tests/RunCMake/target_link_libraries/Separate-PRIVATE-LINK_PRIVATE-uses-result.txt b/Tests/RunCMake/target_link_libraries/Separate-PRIVATE-LINK_PRIVATE-uses-result.txt
new file mode 100644
index 0000000000..573541ac97
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/Separate-PRIVATE-LINK_PRIVATE-uses-result.txt
@@ -0,0 +1 @@
+0
diff --git a/Tests/RunCMake/target_link_libraries/Separate-PRIVATE-LINK_PRIVATE-uses.cmake b/Tests/RunCMake/target_link_libraries/Separate-PRIVATE-LINK_PRIVATE-uses.cmake
new file mode 100644
index 0000000000..e32891d6dd
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/Separate-PRIVATE-LINK_PRIVATE-uses.cmake
@@ -0,0 +1,9 @@
+
+enable_language(CXX)
+
+add_library(foo empty_vs6_1.cpp)
+add_library(bar empty_vs6_2.cpp)
+add_library(bat empty_vs6_3.cpp)
+
+target_link_libraries(foo LINK_PRIVATE bar)
+target_link_libraries(foo PRIVATE bat)
diff --git a/Tests/RunCMake/target_link_libraries/empty.cpp b/Tests/RunCMake/target_link_libraries/empty.cpp
new file mode 100644
index 0000000000..bfbbddeb90
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/empty.cpp
@@ -0,0 +1,7 @@
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int empty()
+{
+  return 0;
+}
diff --git a/Tests/RunCMake/target_link_libraries/empty_vs6_1.cpp b/Tests/RunCMake/target_link_libraries/empty_vs6_1.cpp
new file mode 100644
index 0000000000..7efedabfa3
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/empty_vs6_1.cpp
@@ -0,0 +1 @@
+#include "empty.cpp"
diff --git a/Tests/RunCMake/target_link_libraries/empty_vs6_2.cpp b/Tests/RunCMake/target_link_libraries/empty_vs6_2.cpp
new file mode 100644
index 0000000000..7efedabfa3
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/empty_vs6_2.cpp
@@ -0,0 +1 @@
+#include "empty.cpp"
diff --git a/Tests/RunCMake/target_link_libraries/empty_vs6_3.cpp b/Tests/RunCMake/target_link_libraries/empty_vs6_3.cpp
new file mode 100644
index 0000000000..7efedabfa3
--- /dev/null
+++ b/Tests/RunCMake/target_link_libraries/empty_vs6_3.cpp
@@ -0,0 +1 @@
+#include "empty.cpp"