Genex: Add $<LINK_LIBRARY:...>

This generator expression offers the capability, for the link step, to
decorate libraries with prefix/suffix flags and/or adding any specific flag for each
library.

Fixes: #22812, #18751, #20078, #22703

Help/manual/cmake-generator-expressions.7.rst

@@ -1113,6 +1113,75 @@ Output-Related Expressions
   property, perhaps via the :command:`target_link_libraries` command,
   to specify private link dependencies without other usage requirements.
 
+.. genex:: $<LINK_LIBRARY:feature,library-list>
+
+  .. versionadded:: 3.24
+
+  Manage how libraries are specified during the link step.
+  This expression may be used to specify how to link libraries in a target.
+  For example:
+
+  .. code-block:: cmake
+
+    add_library(lib1 STATIC ...)
+    add_library(lib2 ...)
+    target_link_libraries(lib2 PRIVATE $<LINK_LIBRARY:whole_archive,lib1>)
+
+  This specify to use the ``lib1`` target with feature ``whole_archive`` for
+  linking target ``lib2``. The feature must have be defined by
+  :variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>` variable or, if
+  :variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>_SUPPORTED` is false,
+  by :variable:`CMAKE_LINK_USING_<FEATURE>` variable.
+
+  .. note::
+
+    The evaluation of this generator expression will use, for the following
+    variables, the values defined at the level of the creation of the target:
+
+    * :variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>_SUPPORTED`
+    * :variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>`
+    * :variable:`CMAKE_LINK_USING_<FEATURE>_SUPPORTED`
+    * :variable:`CMAKE_LINK_USING_<FEATURE>`
+
+  This expression can only be used to specify link libraries (i.e. part of
+  :command:`link_libraries` or :command:`target_link_libraries` commands and
+  :prop_tgt:`LINK_LIBRARIES` or :prop_tgt:`INTERFACE_LINK_LIBRARIES` target
+  properties).
+
+  .. note::
+
+    If this expression appears in the :prop_tgt:`INTERFACE_LINK_LIBRARIES`
+    property of a target, it will be included in the imported target generated
+    by :command:`install(EXPORT)` command. It is the responsibility of the
+    environment consuming this import to define the link feature used by this
+    expression.
+
+  The ``library-list`` argument can hold CMake targets or external libraries.
+  Any ``CMake`` target of type :ref:`OBJECT <Object Libraries>` or
+  :ref:`INTERFACE <Interface Libraries>` will be ignored by this expression and
+  will be handled in the standard way.
+
+  Each target or external library involved in the link step must have only one
+  kind of feature (the absence of feature is also incompatible with any
+  feature). For example:
+
+  .. code-block:: cmake
+
+    add_library(lib1 ...)
+
+    add_library(lib2 ...)
+    target_link_libraries(lib2 PUBLIC $<LINK_LIBRARY:feature1,lib1>)
+
+    add_library(lib3 ...)
+    target_link_libraries(lib3 PRIVATE lib1 lib2)
+    # an error will be raised here because lib1 has two different features
+
+  .. note::
+
+    This expression does not guarantee that the list of specified libraries
+    will be kept grouped. So, constructs like ``start-group`` and
+    ``end-group``, as supported by ``GNU ld``, cannot be used.
+
 .. genex:: $<INSTALL_INTERFACE:...>
 
   Content of ``...`` when the property is exported using :command:`install(EXPORT)`,

Help/manual/cmake-variables.7.rst

@@ -440,6 +440,8 @@ Variables that Control the Build
    /variable/CMAKE_LANG_LINKER_LAUNCHER
    /variable/CMAKE_LANG_LINK_LIBRARY_FILE_FLAG
    /variable/CMAKE_LANG_LINK_LIBRARY_FLAG
+   /variable/CMAKE_LANG_LINK_USING_FEATURE
+   /variable/CMAKE_LANG_LINK_USING_FEATURE_SUPPORTED
    /variable/CMAKE_LANG_LINK_WHAT_YOU_USE_FLAG
    /variable/CMAKE_LANG_VISIBILITY_PRESET
    /variable/CMAKE_LIBRARY_OUTPUT_DIRECTORY
@@ -450,6 +452,8 @@ Variables that Control the Build
    /variable/CMAKE_LINK_INTERFACE_LIBRARIES
    /variable/CMAKE_LINK_LIBRARY_FILE_FLAG
    /variable/CMAKE_LINK_LIBRARY_FLAG
+   /variable/CMAKE_LINK_USING_FEATURE
+   /variable/CMAKE_LINK_USING_FEATURE_SUPPORTED
    /variable/CMAKE_LINK_WHAT_YOU_USE
    /variable/CMAKE_LINK_WHAT_YOU_USE_CHECK
    /variable/CMAKE_MACOSX_BUNDLE

Help/release/dev/Genex-LINK_LIBRARY.rst

@@ -0,0 +1,8 @@
+Genex-LINK_LIBRARY
+------------------
+
+* The :genex:`LINK_LIBRARY` generator expression was added to manage how
+  libraries are specified during the link step. The variables
+  :variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>` and
+  :variable:`CMAKE_LINK_USING_<FEATURE>` are used to define features usable by
+  the :genex:`LINK_LIBRARY` generator expression.

Help/variable/CMAKE_LANG_LINK_USING_FEATURE.rst

@@ -0,0 +1,19 @@
+CMAKE_<LANG>_LINK_USING_<FEATURE>
+---------------------------------
+
+.. versionadded:: 3.24
+
+This variable defines, for the specified ``<FEATURE>`` and the linker language
+``<LANG>``, the expression expected by the linker when libraries are specified
+using :genex:`LINK_LIBRARY` generator expression.
+
+.. note::
+
+  Feature names defined in all uppercase are reserved to CMake.
+
+See also the associated variable
+:variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>_SUPPORTED` and
+:variable:`CMAKE_LINK_USING_<FEATURE>` variable for the definition of features
+independent from the link language.
+
+.. include:: CMAKE_LINK_USING_FEATURE.txt

Help/variable/CMAKE_LANG_LINK_USING_FEATURE_SUPPORTED.rst

@@ -0,0 +1,13 @@
+CMAKE_<LANG>_LINK_USING_<FEATURE>_SUPPORTED
+-------------------------------------------
+
+.. versionadded:: 3.24
+
+Set to ``TRUE`` if the ``<FEATURE>``, as defined by variable
+:variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>`, is supported for the linker
+language ``<LANG>``.
+
+.. note::
+
+  This variable is evaluated before the more generic variable
+  :variable:`CMAKE_LINK_USING_<FEATURE>_SUPPORTED`.

Help/variable/CMAKE_LINK_USING_FEATURE.rst

@@ -0,0 +1,23 @@
+CMAKE_LINK_USING_<FEATURE>
+--------------------------
+
+.. versionadded:: 3.24
+
+This variable defines, for the specified ``FEATURE``, the expression expected
+by the linker, regardless the linker language, when libraries are specified
+using :genex:`LINK_LIBRARY` generator expression.
+
+.. note::
+
+  Feature names defined in all uppercase are reserved to CMake.
+
+See also the associated variable
+:variable:`CMAKE_LINK_USING_<FEATURE>_SUPPORTED` and
+:variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>` variable for the definition of
+features dependent from the link language.
+
+This variable will be used by :genex:`LINK_LIBRARY` generator expression if,
+for the linker language, the variable
+:variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>_SUPPORTED` is false or not set.
+
+.. include:: CMAKE_LINK_USING_FEATURE.txt

Help/variable/CMAKE_LINK_USING_FEATURE.txt

@@ -0,0 +1,111 @@
+
+It can contain one or three elements.
+
+::
+
+  [<PREFIX>] <LIBRARY_EXPRESSION> [<SUFFIX>]
+
+When ``<PREFIX>`` and/or ``<SUFFIX>`` are specified, they encapsulate the list
+of libraries.
+
+.. note::
+
+  Even if ``<PREFIX>`` and ``<SUFFIX>`` are specified, there is not guarantee
+  that the list of specified libraries, as part of :genex:`LINK_LIBRARY`
+  generator expression, will be kept grouped. So, constructs like
+  ``start-group`` and ``end-group``, as supported by ``GNU ld``, cannot be
+  used.
+
+``<LIBRARY_EXPRESSION>`` is used to specify the decoration for each
+library. For that purpose, the patterns ``<LIBRARY>``, ``<LINK_ITEM>``, and
+``<LIB_ITEM>`` are available:
+
+* ``<LIBRARY>`` is expanded to the library as computed by CMake.
+* ``<LINK_ITEM>`` is expanded to the same expression as if the library was
+  specified in the standard way.
+* ``<LIB_ITEM>`` is equivalent to ``<LIBRARY>`` for CMake targets and is
+  expanded to the item specified by the user for external libraries.
+
+Moreover, it is possible to have different decorations for paths (CMake targets
+and external libraries specified with absolute paths) and other items specified
+by name. For that purpose, ``PATH{}`` and ``NAME{}`` wrappers can be used.
+
+For all three elements of this variable, the ``LINKER:`` prefix can be used:
+
+  .. include:: ../command/LINK_OPTIONS_LINKER.txt
+    :start-line: 3
+
+Examples
+^^^^^^^^
+
+Loading a whole static library
+""""""""""""""""""""""""""""""
+
+A common need is the capability to load a whole static library. This capability
+is offered by various environments but with a specific syntax:
+
+.. code-block:: cmake
+
+  set(CMAKE_C_LINK_USING_whole_archive_SUPPORTED TRUE)
+  if(CMAKE_C_COMPILER_ID STREQUAL "AppleClang")
+    set(CMAKE_C_LINK_USING_whole_archive "-force_load <LIB_ITEM>")
+  elseif(CMAKE_C_COMPILER_ID STREQUAL "GNU"
+         AND CMAKE_SYSTEM_NAME STREQUAL "Linux")
+    set(CMAKE_C_LINK_USING_whole_archive "LINKER:--push-state,--whole-archive"
+                                         "<LINK_ITEM>"
+                                         "LINKER:--pop-state")
+  elseif(CMAKE_C_COMPILER_ID STREQUAL "MSVC")
+    set(CMAKE_C_LINK_USING_whole_archive "/WHOLEARCHIVE:<LIBRARY>")
+  else()
+    # feature not yet supported for the other environments
+    set(CMAKE_C_LINK_USING_whole_archive_SUPPORTED FALSE)
+  endif()
+
+  add_library(lib1 STATIC ...)
+
+  add_library(lib2 SHARED ...)
+  if(CMAKE_C_LINK_USING_whole_archive_SUPPORTED)
+    target_link_libraries(lib2 PRIVATE
+      $<LINK_LIBRARY:whole_archive,lib1,$<IF:$<LINK_LANG_AND_ID:C,Clang>,libexternal.a,external>>)
+  else()
+    target_link_libraries(lib2 PRIVATE lib1 external)
+  endif()
+
+CMake will generate the following link expressions:
+
+* ``Clang``: ``-force_load /path/to/lib1.a -force_load libexternal.a``
+* ``GNU``: ``-Wl,--whole-archive /path/to/lib1.a -lexternal -Wl,--no-whole-archive``
+* ``MSVC``: ``/WHOLEARCHIVE:/path/to/lib1.lib /WHOLEARCHIVE:external.lib``
+
+CMake will ensure, when possible, that ``<PREFIX>`` and ``<SUFFIX>`` are
+not repeated for each library.
+
+In case of ``Clang``, the pattern ``<LIB_ITEM>`` is used because we need to
+specify the library as defined by the user, not the name computed by CMake
+(in that case ``external``).
+
+Linking a library as weak
+"""""""""""""""""""""""""
+
+On MacOS, it is possible to link a library in weak mode (the library and all
+references are marked as weak imports), but different flags must be used for a
+library specified by path and by name. This constraint by be solved by using
+``PATH{}`` and ``NAME{}`` wrappers:
+
+.. code-block:: cmake
+
+  if (CMAKE_C_COMPILER_ID STREQUAL "AppleClang")
+    set(CMAKE_LINK_USING_weak_library "PATH{-weak_library <LIBRARY>}NAME{LINKER:-weak-l<LIB_ITEM>}")
+    set(CMAKE_LINK_USING_weak_library_SUPPORTED TRUE)
+  endif()
+
+  add_library(lib SHARED ...)
+  add_executable(main ...)
+  if(CMAKE_LINK_USING_weak_library_SUPPORTED)
+    target_link_libraries(main PRIVATE $<LINK_LIBRARY:weak_library,lib,external>)
+  else()
+    target_link_libraries(main PRIVATE lib external)
+  endif()
+
+CMake will generate the following link expression:
+``-weak_library /path/to/lib -Xlinker -weak-lexternal``

Help/variable/CMAKE_LINK_USING_FEATURE_SUPPORTED.rst

@@ -0,0 +1,14 @@
+CMAKE_LINK_USING_<FEATURE>_SUPPORTED
+------------------------------------
+
+.. versionadded:: 3.24
+
+Set to ``TRUE`` if the ``<FEATURE>``, as defined by variable
+:variable:`CMAKE_LINK_USING_<FEATURE>`, is supported regardless the linker
+language.
+
+.. note::
+
+  This variable is evaluated if, and only if, the variable
+  :variable:`CMAKE_<LANG>_LINK_USING_<FEATURE>_SUPPORTED` evaluates to
+  ``FALSE``.

Source/cmComputeLinkDepends.cxx

@@ -11,6 +11,7 @@
 #include <utility>
 
 #include <cm/memory>
+#include <cmext/string_view>
 
 #include "cmComputeComponentGraph.h"
 #include "cmGeneratorTarget.h"
@@ -18,6 +19,7 @@
 #include "cmListFileCache.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
+#include "cmMessageType.h"
 #include "cmRange.h"
 #include "cmStateTypes.h"
 #include "cmStringAlgorithms.h"
@@ -174,8 +176,33 @@ items that we know the linker will re-use automatically (shared libs).
 
 */
 
+namespace {
+const auto LL_BEGIN = "<LINK_LIBRARY:"_s;
+const auto LL_END = "</LINK_LIBRARY:"_s;
+
+inline std::string ExtractFeature(std::string const& item)
+{
+  return item.substr(LL_BEGIN.length(),
+                     item.find('>', LL_BEGIN.length()) - LL_BEGIN.length());
+}
+
+bool IsFeatureSupported(cmMakefile* makefile, std::string const& linkLanguage,
+                        std::string const& feature)
+{
+  auto featureSupported =
+    cmStrCat("CMAKE_", linkLanguage, "_LINK_USING_", feature, "_SUPPORTED");
+  if (makefile->GetDefinition(featureSupported).IsOn()) {
+    return true;
+  }
+
+  featureSupported = cmStrCat("CMAKE_LINK_USING_", feature, "_SUPPORTED");
+  return makefile->GetDefinition(featureSupported).IsOn();
+}
+}
+
 cmComputeLinkDepends::cmComputeLinkDepends(const cmGeneratorTarget* target,
-                                           const std::string& config)
+                                           const std::string& config,
+                                           const std::string& linkLanguage)
 {
   // Store context information.
   this->Target = target;
@@ -183,6 +210,7 @@ cmComputeLinkDepends::cmComputeLinkDepends(const cmGeneratorTarget* target,
   this->GlobalGenerator =
     this->Target->GetLocalGenerator()->GetGlobalGenerator();
   this->CMakeInstance = this->GlobalGenerator->GetCMakeInstance();
+  this->LinkLanguage = linkLanguage;
 
   // The configuration being linked.
   this->HasConfig = !config.empty();
@@ -249,7 +277,7 @@ cmComputeLinkDepends::Compute()
   }
 
   // Compute the final ordering.
-  this->OrderLinkEntires();
+  this->OrderLinkEntries();
 
   // Compute the final set of link entries.
   // Iterate in reverse order so we can keep only the last occurrence
@@ -281,32 +309,33 @@ cmComputeLinkDepends::Compute()
   return this->FinalLinkEntries;
 }
 
-std::map<cmLinkItem, int>::iterator cmComputeLinkDepends::AllocateLinkEntry(
-  cmLinkItem const& item)
+std::pair<std::map<cmLinkItem, int>::iterator, bool>
+cmComputeLinkDepends::AllocateLinkEntry(cmLinkItem const& item)
 {
   std::map<cmLinkItem, int>::value_type index_entry(
     item, static_cast<int>(this->EntryList.size()));
-  auto lei = this->LinkEntryIndex.insert(index_entry).first;
-  this->EntryList.emplace_back();
-  this->InferredDependSets.emplace_back();
-  this->EntryConstraintGraph.emplace_back();
+  auto lei = this->LinkEntryIndex.insert(index_entry);
+  if (lei.second) {
+    this->EntryList.emplace_back();
+    this->InferredDependSets.emplace_back();
+    this->EntryConstraintGraph.emplace_back();
+  }
   return lei;
 }
 
-int cmComputeLinkDepends::AddLinkEntry(cmLinkItem const& item)
+std::pair<int, bool> cmComputeLinkDepends::AddLinkEntry(cmLinkItem const& item)
 {
+  // Allocate a spot for the item entry.
+  auto lei = this->AllocateLinkEntry(item);
+
   // Check if the item entry has already been added.
-  auto lei = this->LinkEntryIndex.find(item);
-  if (lei != this->LinkEntryIndex.end()) {
+  if (!lei.second) {
     // Yes.  We do not need to follow the item's dependencies again.
-    return lei->second;
+    return { lei.first->second, false };
   }
 
-  // Allocate a spot for the item entry.
-  lei = this->AllocateLinkEntry(item);
-
   // Initialize the item entry.
-  int index = lei->second;
+  int index = lei.first->second;
   LinkEntry& entry = this->EntryList[index];
   entry.Item = BT<std::string>(item.AsStr(), item.Backtrace);
   entry.Target = item.Target;
@@ -332,22 +361,21 @@ int cmComputeLinkDepends::AddLinkEntry(cmLinkItem const& item)
     }
   }
 
-  return index;
+  return { index, true };
 }
 
 void cmComputeLinkDepends::AddLinkObject(cmLinkItem const& item)
 {
+  // Allocate a spot for the item entry.
+  auto lei = this->AllocateLinkEntry(item);
+
   // Check if the item entry has already been added.
-  auto lei = this->LinkEntryIndex.find(item);
-  if (lei != this->LinkEntryIndex.end()) {
+  if (!lei.second) {
     return;
   }
 
-  // Allocate a spot for the item entry.
-  lei = this->AllocateLinkEntry(item);
-
   // Initialize the item entry.
-  int index = lei->second;
+  int index = lei.first->second;
   LinkEntry& entry = this->EntryList[index];
   entry.Item = BT<std::string>(item.AsStr(), item.Backtrace);
   entry.IsObject = true;
@@ -423,14 +451,14 @@ void cmComputeLinkDepends::QueueSharedDependencies(
 
 void cmComputeLinkDepends::HandleSharedDependency(SharedDepEntry const& dep)
 {
-  // Check if the target already has an entry.
-  auto lei = this->LinkEntryIndex.find(dep.Item);
-  if (lei == this->LinkEntryIndex.end()) {
-    // Allocate a spot for the item entry.
-    lei = this->AllocateLinkEntry(dep.Item);
+  // Allocate a spot for the item entry.
+  auto lei = this->AllocateLinkEntry(dep.Item);
+  int index = lei.first->second;
 
+  // Check if the target does not already has an entry.
+  if (lei.second) {
     // Initialize the item entry.
-    LinkEntry& entry = this->EntryList[lei->second];
+    LinkEntry& entry = this->EntryList[index];
     entry.Item = BT<std::string>(dep.Item.AsStr(), dep.Item.Backtrace);
     entry.Target = dep.Item.Target;
 
@@ -441,7 +469,6 @@ void cmComputeLinkDepends::HandleSharedDependency(SharedDepEntry const& dep)
   }
 
   // Get the link entry for this target.
-  int index = lei->second;
   LinkEntry& entry = this->EntryList[index];
 
   // This shared library dependency must follow the item that listed
@@ -541,6 +568,7 @@ void cmComputeLinkDepends::AddLinkEntries(int depender_index,
 {
   // Track inferred dependency sets implied by this list.
   std::map<int, DependSet> dependSets;
+  std::string feature;
 
   // Loop over the libraries linked directly by the depender.
   for (T const& l : libs) {
@@ -550,9 +578,86 @@ void cmComputeLinkDepends::AddLinkEntries(int depender_index,
     if (item.AsStr() == this->Target->GetName() || item.AsStr().empty()) {
       continue;
     }
+    if (cmHasPrefix(item.AsStr(), LL_BEGIN) &&
+        cmHasSuffix(item.AsStr(), '>')) {
+      feature = ExtractFeature(item.AsStr());
+      // emit a warning if an undefined feature is used as part of
+      // an imported target
+      if (depender_index >= 0) {
+        const auto& depender = this->EntryList[depender_index];
+        if (depender.Target != nullptr && depender.Target->IsImported() &&
+            !IsFeatureSupported(this->Makefile, this->LinkLanguage, feature)) {
+          this->CMakeInstance->IssueMessage(
+            MessageType::AUTHOR_ERROR,
+            cmStrCat("The 'IMPORTED' target '", depender.Target->GetName(),
+                     "' uses the generator-expression '$<LINK_LIBRARY>' with "
+                     "the feature '",
+                     feature,
+                     "', which is undefined or unsupported.\nDid you miss to "
+                     "define it by setting variables \"CMAKE_",
+                     this->LinkLanguage, "_LINK_USING_", feature,
+                     "\" and \"CMAKE_", this->LinkLanguage, "_LINK_USING_",
+                     feature, "_SUPPORTED\"?"),
+            this->Target->GetBacktrace());
+        }
+      }
+      continue;
+    }
+    if (cmHasPrefix(item.AsStr(), LL_END) && cmHasSuffix(item.AsStr(), '>')) {
+      feature.clear();
+      continue;
+    }
 
     // Add a link entry for this item.
-    int dependee_index = this->AddLinkEntry(l);
+    auto ale = this->AddLinkEntry(item);
+    int dependee_index = ale.first;
+    LinkEntry& entry = this->EntryList[dependee_index];
+    if (!feature.empty()) {
+      if (ale.second) {
+        // current item not yet defined
+        if (entry.Target != nullptr &&
+            (entry.Target->GetType() ==
+               cmStateEnums::TargetType::OBJECT_LIBRARY ||
+             entry.Target->GetType() ==
+               cmStateEnums::TargetType::INTERFACE_LIBRARY)) {
+          this->CMakeInstance->IssueMessage(
+            MessageType::AUTHOR_WARNING,
+            cmStrCat("The feature '", feature,
+                     "', specified as part of a generator-expression "
+                     "'$",
+                     LL_BEGIN, feature, ">', will not be applied to the ",
+                     (entry.Target->GetType() ==
+                          cmStateEnums::TargetType::OBJECT_LIBRARY
+                        ? "OBJECT"
+                        : "INTERFACE"),
+                     " library '", entry.Item.Value, "'."),
+            this->Target->GetBacktrace());
+        } else {
+          entry.Feature = feature;
+        }
+      }
+    }
+
+    bool supportedItem = entry.Target == nullptr ||
+      (entry.Target->GetType() != cmStateEnums::TargetType::OBJECT_LIBRARY &&
+       entry.Target->GetType() != cmStateEnums::TargetType::INTERFACE_LIBRARY);
+
+    if (supportedItem && entry.Feature != feature) {
+      // incompatibles features occurred
+      this->CMakeInstance->IssueMessage(
+        MessageType::FATAL_ERROR,
+        cmStrCat(
+          "Impossible to link target '", this->Target->GetName(),
+          "' because the link item '", entry.Item.Value, "', specified ",
+          (feature.empty() ? "without any feature"
+                           : cmStrCat("with the feature '", feature, '\'')),
+          ", has already occurred ",
+          (entry.Feature.empty()
+             ? "without any feature"
+             : cmStrCat("with the feature '", entry.Feature, '\'')),
+          ", which is not allowed."),
+        this->Target->GetBacktrace());
+    }
 
     // The dependee must come after the depender.
     if (depender_index >= 0) {
@@ -667,7 +772,7 @@ void cmComputeLinkDepends::DisplayConstraintGraph()
   fprintf(stderr, "%s\n", e.str().c_str());
 }
 
-void cmComputeLinkDepends::OrderLinkEntires()
+void cmComputeLinkDepends::OrderLinkEntries()
 {
   // Compute the DAG of strongly connected components.  The algorithm
   // used by cmComputeComponentGraph should identify the components in
@@ -869,10 +974,14 @@ void cmComputeLinkDepends::DisplayFinalEntries()
   fprintf(stderr, "target [%s] links to:\n", this->Target->GetName().c_str());
   for (LinkEntry const& lei : this->FinalLinkEntries) {
     if (lei.Target) {
-      fprintf(stderr, "  target [%s]\n", lei.Target->GetName().c_str());
+      fprintf(stderr, "  target [%s]", lei.Target->GetName().c_str());
     } else {
-      fprintf(stderr, "  item [%s]\n", lei.Item.Value.c_str());
+      fprintf(stderr, "  item [%s]", lei.Item.Value.c_str());
+    }
+    if (!lei.Feature.empty()) {
+      fprintf(stderr, ", feature [%s]", lei.Feature.c_str());
     }
+    fprintf(stderr, "\n");
   }
   fprintf(stderr, "\n");
 }

Source/cmComputeLinkDepends.h

@@ -30,7 +30,8 @@ class cmComputeLinkDepends
 {
 public:
   cmComputeLinkDepends(cmGeneratorTarget const* target,
-                       const std::string& config);
+                       const std::string& config,
+                       const std::string& linkLanguage);
   ~cmComputeLinkDepends();
 
   cmComputeLinkDepends(const cmComputeLinkDepends&) = delete;
@@ -51,6 +52,9 @@ public:
     bool IsSharedDep = false;
     bool IsFlag = false;
     bool IsObject = false;
+    // The following member is for the management of items specified
+    // through genex $<LINK_LIBRARY:...>
+    std::string Feature;
   };
 
   using EntryVector = std::vector<LinkEntry>;
@@ -68,12 +72,13 @@ private:
   cmMakefile* Makefile;
   cmGlobalGenerator const* GlobalGenerator;
   cmake* CMakeInstance;
+  std::string LinkLanguage;
   std::string Config;
   EntryVector FinalLinkEntries;
 
-  std::map<cmLinkItem, int>::iterator AllocateLinkEntry(
+  std::pair<std::map<cmLinkItem, int>::iterator, bool> AllocateLinkEntry(
     cmLinkItem const& item);
-  int AddLinkEntry(cmLinkItem const& item);
+  std::pair<int, bool> AddLinkEntry(cmLinkItem const& item);
   void AddLinkObject(cmLinkItem const& item);
   void AddVarLinkEntries(int depender_index, const char* value);
   void AddDirectLinkEntries();
@@ -131,7 +136,7 @@ private:
   void DisplayConstraintGraph();
 
   // Ordering algorithm.
-  void OrderLinkEntires();
+  void OrderLinkEntries();
   std::vector<char> ComponentVisited;
   std::vector<int> ComponentOrder;
 

Source/cmComputeLinkInformation.cxx

@@ -19,6 +19,7 @@
 #include "cmMessageType.h"
 #include "cmOrderDirectories.h"
 #include "cmOutputConverter.h"
+#include "cmPlaceholderExpander.h"
 #include "cmPolicies.h"
 #include "cmState.h"
 #include "cmStateTypes.h"
@@ -344,6 +345,27 @@ cmComputeLinkInformation::cmComputeLinkInformation(
     this->LinkWithRuntimePath = this->Makefile->IsOn(var);
   }
 
+  // Define some Feature descriptors to handle standard library and object link
+  if (!this->GetLibLinkFileFlag().empty()) {
+    this->LibraryFeatureDescriptors.emplace(
+      "__CMAKE_LINK_LIBRARY",
+      FeatureDescriptor{ "__CMAKE_LINK_LIBRARY",
+                         cmStrCat(this->GetLibLinkFileFlag(), "<LIBRARY>") });
+  }
+  if (!this->GetObjLinkFileFlag().empty()) {
+    this->LibraryFeatureDescriptors.emplace(
+      "__CMAKE_LINK_OBJECT",
+      FeatureDescriptor{ "__CMAKE_LINK_OBJECT",
+                         cmStrCat(this->GetObjLinkFileFlag(), "<LIBRARY>") });
+  }
+  if (!this->LoaderFlag->empty()) {
+    // Define a Feature descriptor for the link of an executable with exports
+    this->LibraryFeatureDescriptors.emplace(
+      "__CMAKE_LINK_EXECUTABLE",
+      FeatureDescriptor{ "__CMAKE_LINK_EXECUTABLE",
+                         cmStrCat(this->LoaderFlag, "<LIBRARY>") });
+  }
+
   // Check the platform policy for missing soname case.
   this->NoSONameUsesPath =
     this->Makefile->IsOn("CMAKE_PLATFORM_USES_PATH_WHEN_NO_SONAME");
@@ -510,12 +532,40 @@ bool cmComputeLinkInformation::Compute()
   }
 
   // Compute the ordered link line items.
-  cmComputeLinkDepends cld(this->Target, this->Config);
+  cmComputeLinkDepends cld(this->Target, this->Config, this->LinkLanguage);
   cld.SetOldLinkDirMode(this->OldLinkDirMode);
   cmComputeLinkDepends::EntryVector const& linkEntries = cld.Compute();
+  FeatureDescriptor const* currentFeature = nullptr;
 
   // Add the link line items.
   for (cmComputeLinkDepends::LinkEntry const& linkEntry : linkEntries) {
+    if (currentFeature != nullptr &&
+        linkEntry.Feature != currentFeature->Name) {
+      // emit feature suffix, if any
+      if (!currentFeature->Suffix.empty()) {
+        this->Items.emplace_back(
+          BT<std::string>{ currentFeature->Suffix,
+                           this->Items.back().Value.Backtrace },
+          ItemIsPath::No);
+      }
+      currentFeature = nullptr;
+    }
+
+    if (!linkEntry.Feature.empty() &&
+        (currentFeature == nullptr ||
+         linkEntry.Feature != currentFeature->Name)) {
+      if (!this->AddLibraryFeature(linkEntry.Feature)) {
+        continue;
+      }
+      currentFeature = this->FindLibraryFeature(linkEntry.Feature);
+      // emit feature prefix, if any
+      if (!currentFeature->Prefix.empty()) {
+        this->Items.emplace_back(
+          BT<std::string>{ currentFeature->Prefix, linkEntry.Item.Backtrace },
+          ItemIsPath::No);
+      }
+    }
+
     if (linkEntry.IsSharedDep) {
       this->AddSharedDepItem(linkEntry);
     } else {
@@ -523,6 +573,16 @@ bool cmComputeLinkInformation::Compute()
     }
   }
 
+  if (currentFeature != nullptr) {
+    // emit feature suffix, if any
+    if (!currentFeature->Suffix.empty()) {
+      this->Items.emplace_back(
+        BT<std::string>{ currentFeature->Suffix,
+                         this->Items.back().Value.Backtrace },
+        ItemIsPath::No);
+    }
+  }
+
   // Restore the target link type so the correct system runtime
   // libraries are found.
   cmValue lss = this->Target->GetProperty("LINK_SEARCH_END_STATIC");
@@ -575,6 +635,270 @@ bool cmComputeLinkInformation::Compute()
   return true;
 }
 
+namespace {
+void FinalizeFeatureFormat(std::string& format, const std::string& activeTag,
+                           const std::string& otherTag)
+{
+  auto pos = format.find(otherTag);
+  if (pos != std::string::npos) {
+    format.erase(pos, format.find('}', pos) - pos + 1);
+  }
+  pos = format.find(activeTag);
+  if (pos != std::string::npos) {
+    format.erase(pos, activeTag.length());
+    pos = format.find('}', pos);
+    if (pos != std::string::npos) {
+      format.erase(pos, 1);
+    }
+  }
+}
+
+bool IsValidFeatureFormat(const std::string& format)
+{
+  return format.find("<LIBRARY>") != std::string::npos ||
+    format.find("<LIB_ITEM>") != std::string::npos ||
+    format.find("<LINK_ITEM>") != std::string::npos;
+}
+}
+
+bool cmComputeLinkInformation::AddLibraryFeature(std::string const& feature)
+{
+  auto it = this->LibraryFeatureDescriptors.find(feature);
+  if (it != this->LibraryFeatureDescriptors.end()) {
+    return it->second.Supported;
+  }
+
+  auto featureName =
+    cmStrCat("CMAKE_", this->LinkLanguage, "_LINK_USING_", feature);
+  cmValue featureSupported =
+    this->Makefile->GetDefinition(cmStrCat(featureName, "_SUPPORTED"));
+  if (!featureSupported.IsOn()) {
+    featureName = cmStrCat("CMAKE_LINK_USING_", feature);
+    featureSupported =
+      this->Makefile->GetDefinition(cmStrCat(featureName, "_SUPPORTED"));
+  }
+  if (!featureSupported.IsOn()) {
+    this->LibraryFeatureDescriptors.emplace(feature, FeatureDescriptor{});
+
+    this->CMakeInstance->IssueMessage(
+      MessageType::FATAL_ERROR,
+      cmStrCat(
+        "Feature '", feature,
+        "', specified through generator-expression '$<LINK_LIBRARY>' to "
+        "link target '",
+        this->Target->GetName(), "', is not supported for the '",
+        this->LinkLanguage, "' link language."),
+      this->Target->GetBacktrace());
+
+    return false;
+  }
+
+  cmValue langFeature = this->Makefile->GetDefinition(featureName);
+  if (!langFeature) {
+    this->LibraryFeatureDescriptors.emplace(feature, FeatureDescriptor{});
+
+    this->CMakeInstance->IssueMessage(
+      MessageType::FATAL_ERROR,
+      cmStrCat(
+        "Feature '", feature,
+        "', specified through generator-expression '$<LINK_LIBRARY>' to "
+        "link target '",
+        this->Target->GetName(), "', is not defined for the '",
+        this->LinkLanguage, "' link language."),
+      this->Target->GetBacktrace());
+
+    return false;
+  }
+
+  auto items =
+    cmExpandListWithBacktrace(langFeature, this->Target->GetBacktrace(), true);
+
+  if ((items.size() == 1 && !IsValidFeatureFormat(items.front().Value)) ||
+      (items.size() == 3 && !IsValidFeatureFormat(items[1].Value))) {
+    this->LibraryFeatureDescriptors.emplace(feature, FeatureDescriptor{});
+    this->CMakeInstance->IssueMessage(
+      MessageType::FATAL_ERROR,
+      cmStrCat("Feature '", feature, "', specified by variable '", featureName,
+               "', is malformed (\"<LIBRARY>\", \"<LIB_ITEM>\", or "
+               "\"<LINK_ITEM>\" patterns "
+               "are missing) and cannot be used to link target '",
+               this->Target->GetName(), "'."),
+      this->Target->GetBacktrace());
+
+    return false;
+  }
+
+  // now, handle possible "PATH{}" and "NAME{}" patterns
+  if (items.size() == 1) {
+    items.push_back(items.front());
+    FinalizeFeatureFormat(items[0].Value, "PATH{", "NAME{");
+    FinalizeFeatureFormat(items[1].Value, "NAME{", "PATH{");
+  } else if (items.size() == 3) {
+    items.insert(items.begin() + 1, items[1]);
+    FinalizeFeatureFormat(items[1].Value, "PATH{", "NAME{");
+    FinalizeFeatureFormat(items[2].Value, "NAME{", "PATH{");
+  } else {
+    this->LibraryFeatureDescriptors.emplace(feature, FeatureDescriptor{});
+    this->CMakeInstance->IssueMessage(
+      MessageType::FATAL_ERROR,
+      cmStrCat("Feature '", feature, "', specified by variable '", featureName,
+               "', is malformed (wrong number of elements) and cannot be used "
+               "to link target '",
+               this->Target->GetName(), "'."),
+      this->Target->GetBacktrace());
+
+    return false;
+  }
+  if ((items.size() == 2 && !IsValidFeatureFormat(items[0].Value)) ||
+      (items.size() == 4 && !IsValidFeatureFormat(items[1].Value))) {
+    // PATH{} has wrong format
+    this->LibraryFeatureDescriptors.emplace(feature, FeatureDescriptor{});
+    this->CMakeInstance->IssueMessage(
+      MessageType::FATAL_ERROR,
+      cmStrCat("Feature '", feature, "', specified by variable '", featureName,
+               "', is malformed (\"<LIBRARY>\", \"<LIB_ITEM>\", or "
+               "\"<LINK_ITEM>\" patterns "
+               "are missing for \"PATH{}\" alternative) and cannot be used to "
+               "link target '",
+               this->Target->GetName(), "'."),
+      this->Target->GetBacktrace());
+
+    return false;
+  }
+  if ((items.size() == 2 && !IsValidFeatureFormat(items[1].Value)) ||
+      (items.size() == 4 && !IsValidFeatureFormat(items[2].Value))) {
+    // NAME{} has wrong format
+    this->LibraryFeatureDescriptors.emplace(feature, FeatureDescriptor{});
+    this->CMakeInstance->IssueMessage(
+      MessageType::FATAL_ERROR,
+      cmStrCat("Feature '", feature, "', specified by variable '", featureName,
+               "', is malformed (\"<LIBRARY>\", \"<LIB_ITEM>\", or "
+               "\"<LINK_ITEM>\" patterns "
+               "are missing for \"NAME{}\" alternative) and cannot be used to "
+               "link target '",
+               this->Target->GetName(), "'."),
+      this->Target->GetBacktrace());
+
+    return false;
+  }
+
+  // replace LINKER: pattern
+  this->Target->ResolveLinkerWrapper(items, this->LinkLanguage, true);
+
+  if (items.size() == 2) {
+    this->LibraryFeatureDescriptors.emplace(
+      feature, FeatureDescriptor{ feature, items[0].Value, items[1].Value });
+  } else {
+    this->LibraryFeatureDescriptors.emplace(
+      feature,
+      FeatureDescriptor{ feature, items[0].Value, items[1].Value,
+                         items[2].Value, items[3].Value });
+  }
+
+  return true;
+}
+
+cmComputeLinkInformation::FeatureDescriptor const&
+cmComputeLinkInformation::GetLibraryFeature(std::string const& feature) const
+{
+  return this->LibraryFeatureDescriptors.find(feature)->second;
+}
+cmComputeLinkInformation::FeatureDescriptor const*
+cmComputeLinkInformation::FindLibraryFeature(std::string const& feature) const
+{
+  auto it = this->LibraryFeatureDescriptors.find(feature);
+  if (it == this->LibraryFeatureDescriptors.end()) {
+    return nullptr;
+  }
+
+  return &it->second;
+}
+
+namespace {
+class FeaturePlaceHolderExpander : public cmPlaceholderExpander
+{
+public:
+  FeaturePlaceHolderExpander(const std::string* library,
+                             const std::string* libItem = nullptr,
+                             const std::string* linkItem = nullptr)
+    : Library(library)
+    , LibItem(libItem)
+    , LinkItem(linkItem)
+  {
+  }
+
+private:
+  std::string ExpandVariable(std::string const& variable) override
+  {
+    if (this->Library != nullptr && variable == "LIBRARY") {
+      return *this->Library;
+    }
+    if (this->LibItem != nullptr && variable == "LIB_ITEM") {
+      return *this->LibItem;
+    }
+    if (this->LinkItem != nullptr && variable == "LINK_ITEM") {
+      return *this->LinkItem;
+    }
+
+    return variable;
+  }
+
+  const std::string* Library = nullptr;
+  const std::string* LibItem = nullptr;
+  const std::string* LinkItem = nullptr;
+};
+}
+
+cmComputeLinkInformation::FeatureDescriptor::FeatureDescriptor(
+  std::string name, std::string itemFormat)
+  : Name(std::move(name))
+  , Supported(true)
+  , ItemPathFormat(std::move(itemFormat))
+  , ItemNameFormat(this->ItemPathFormat)
+{
+}
+cmComputeLinkInformation::FeatureDescriptor::FeatureDescriptor(
+  std::string name, std::string itemPathFormat, std::string itemNameFormat)
+  : Name(std::move(name))
+  , Supported(true)
+  , ItemPathFormat(std::move(itemPathFormat))
+  , ItemNameFormat(std::move(itemNameFormat))
+{
+}
+cmComputeLinkInformation::FeatureDescriptor::FeatureDescriptor(
+  std::string name, std::string prefix, std::string itemPathFormat,
+  std::string itemNameFormat, std::string suffix)
+  : Name(std::move(name))
+  , Supported(true)
+  , Prefix(std::move(prefix))
+  , Suffix(std::move(suffix))
+  , ItemPathFormat(std::move(itemPathFormat))
+  , ItemNameFormat(std::move(itemNameFormat))
+{
+}
+
+std::string cmComputeLinkInformation::FeatureDescriptor::GetDecoratedItem(
+  std::string const& library, ItemIsPath isPath) const
+{
+  auto format =
+    isPath == ItemIsPath::Yes ? this->ItemPathFormat : this->ItemNameFormat;
+
+  // replace <LIBRARY>, <LIB_ITEM> and <LINK_ITEM> patterns with library path
+  FeaturePlaceHolderExpander expander(&library, &library, &library);
+  return expander.ExpandVariables(format);
+}
+std::string cmComputeLinkInformation::FeatureDescriptor::GetDecoratedItem(
+  std::string const& library, std::string const& libItem,
+  std::string const& linkItem, ItemIsPath isPath) const
+{
+  auto format =
+    isPath == ItemIsPath::Yes ? this->ItemPathFormat : this->ItemNameFormat;
+
+  // replace <LIBRARY>, <LIB_ITEM> and <LINK_ITEM> patterns
+  FeaturePlaceHolderExpander expander(&library, &libItem, &linkItem);
+  return expander.ExpandVariables(format);
+}
+
 void cmComputeLinkInformation::AddImplicitLinkInfo()
 {
   // The link closure lists all languages whose implicit info is needed.
@@ -657,23 +981,21 @@ void cmComputeLinkInformation::AddItem(LinkEntry const& entry)
     if (impexe && this->LoaderFlag) {
       // This link item is an executable that may provide symbols
       // used by this target.  A special flag is needed on this
-      // platform.  Add it now.
-      std::string linkItem = this->LoaderFlag;
+      // platform.  Add it now using a special feature.
       cmStateEnums::ArtifactType artifact = tgt->HasImportLibrary(config)
         ? cmStateEnums::ImportLibraryArtifact
         : cmStateEnums::RuntimeBinaryArtifact;
-
       std::string exe = tgt->GetFullPath(config, artifact, true);
-      linkItem += exe;
-      this->Items.emplace_back(BT<std::string>(linkItem, item.Backtrace),
-                               ItemIsPath::Yes, ItemIsObject::No, tgt);
+      this->Items.emplace_back(
+        BT<std::string>(exe, item.Backtrace), ItemIsPath::Yes, tgt,
+        this->FindLibraryFeature(
+          entry.Feature.empty() ? "__CMAKE_LINK_EXECUTABLE" : entry.Feature));
       this->Depends.push_back(std::move(exe));
     } else if (tgt->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
       // Add the interface library as an item so it can be considered as part
       // of COMPATIBLE_INTERFACE_ enforcement.  The generators will ignore
       // this for the actual link line.
-      this->Items.emplace_back(std::string(), ItemIsPath::No, ItemIsObject::No,
-                               tgt);
+      this->Items.emplace_back(std::string(), ItemIsPath::No, tgt);
 
       // Also add the item the interface specifies to be used in its place.
       std::string const& libName = tgt->GetImportedLibName(config);
@@ -1098,7 +1420,10 @@ void cmComputeLinkInformation::AddTargetItem(LinkEntry const& entry)
   }
 
   // Now add the full path to the library.
-  this->Items.emplace_back(item, ItemIsPath::Yes, ItemIsObject::No, target);
+  this->Items.emplace_back(item, ItemIsPath::Yes, target,
+                           this->FindLibraryFeature(entry.Feature.empty()
+                                                      ? "__CMAKE_LINK_LIBRARY"
+                                                      : entry.Feature));
 }
 
 void cmComputeLinkInformation::AddFullItem(LinkEntry const& entry)
@@ -1154,9 +1479,12 @@ void cmComputeLinkInformation::AddFullItem(LinkEntry const& entry)
   }
 
   // Now add the full path to the library.
-  this->Items.emplace_back(item, ItemIsPath::Yes,
-                           entry.IsObject ? ItemIsObject::Yes
-                                          : ItemIsObject::No);
+  this->Items.emplace_back(
+    item, ItemIsPath::Yes, nullptr,
+    this->FindLibraryFeature(
+      entry.Feature.empty()
+        ? (entry.IsObject ? "__CMAKE_LINK_OBJECT" : "__CMAKE_LINK_LIBRARY")
+        : entry.Feature));
 }
 
 bool cmComputeLinkInformation::CheckImplicitDirItem(LinkEntry const& entry)
@@ -1221,8 +1549,6 @@ bool cmComputeLinkInformation::CheckImplicitDirItem(LinkEntry const& entry)
   return true;
 }
 
-// void cmComputeLinkInformation::AddUserItem(BT<std::string> const& item,
-//                                            bool pathNotKnown)
 void cmComputeLinkInformation::AddUserItem(LinkEntry const& entry,
                                            bool pathNotKnown)
 {
@@ -1236,8 +1562,8 @@ void cmComputeLinkInformation::AddUserItem(LinkEntry const& entry,
 
   BT<std::string> const& item = entry.Item;
 
-  // Pass flags through untouched.
   if (item.Value[0] == '-' || item.Value[0] == '$' || item.Value[0] == '`') {
+    // Pass flags through untouched.
     // if this is a -l option then we might need to warn about
     // CMP0003 so put it in OldUserFlagItems, if it is not a -l
     // or -Wl,-l (-framework -pthread), then allow it without a
@@ -1322,9 +1648,20 @@ void cmComputeLinkInformation::AddUserItem(LinkEntry const& entry,
   }
 
   // Create an option to ask the linker to search for the library.
-  std::string out = cmStrCat(this->LibLinkFlag, lib, this->LibLinkSuffix);
-  this->Items.emplace_back(BT<std::string>(out, item.Backtrace),
-                           ItemIsPath::No);
+  auto out = cmStrCat(this->LibLinkFlag, lib, this->LibLinkSuffix);
+
+  if (!entry.Feature.empty()) {
+    auto const& feature = this->GetLibraryFeature(entry.Feature);
+    this->Items.emplace_back(
+      BT<std::string>(
+        feature.GetDecoratedItem(cmStrCat(lib, this->LibLinkSuffix),
+                                 item.Value, out, ItemIsPath::No),
+        item.Backtrace),
+      ItemIsPath::No);
+  } else {
+    this->Items.emplace_back(BT<std::string>(out, item.Backtrace),
+                             ItemIsPath::No);
+  }
 
   // Here we could try to find the library the linker will find and
   // add a runtime information entry for it.  It would probably not be
@@ -1374,10 +1711,10 @@ void cmComputeLinkInformation::DropDirectoryItem(BT<std::string> const& item)
   // user.
   this->CMakeInstance->IssueMessage(
     MessageType::WARNING,
-    cmStrCat(
-      "Target \"", this->Target->GetName(),
-      "\" requests linking to directory \"", item.Value,
-      "\".  Targets may link only to libraries.  CMake is dropping the item."),
+    cmStrCat("Target \"", this->Target->GetName(),
+             "\" requests linking to directory \"", item.Value,
+             "\".  Targets may link only to libraries.  CMake is dropping "
+             "the item."),
     item.Backtrace);
 }
 
@@ -1804,8 +2141,8 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
     // Add directories explicitly specified by user
     std::string build_rpath;
     if (this->Target->GetBuildRPATH(this->Config, build_rpath)) {
-      // This will not resolve entries to use $ORIGIN, the user is expected to
-      // do that if necessary.
+      // This will not resolve entries to use $ORIGIN, the user is expected
+      // to do that if necessary.
       cmCLI_ExpandListUnique(build_rpath, runtimeDirs, emitted);
     }
   }

Source/cmComputeLinkInformation.h

@@ -5,6 +5,7 @@
 #include "cmConfigure.h" // IWYU pragma: keep
 
 #include <iosfwd>
+#include <map>
 #include <memory>
 #include <set>
 #include <string>
@@ -28,6 +29,9 @@ class cmake;
  */
 class cmComputeLinkInformation
 {
+private:
+  class FeatureDescriptor;
+
 public:
   cmComputeLinkInformation(cmGeneratorTarget const* target,
                            const std::string& config);
@@ -43,28 +47,33 @@ public:
     Yes,
   };
 
-  enum class ItemIsObject
-  {
-    No,
-    Yes,
-  };
-
   struct Item
   {
-    Item() = default;
     Item(BT<std::string> v, ItemIsPath isPath,
-         ItemIsObject isObject = ItemIsObject::No,
-         cmGeneratorTarget const* target = nullptr)
+         cmGeneratorTarget const* target = nullptr,
+         FeatureDescriptor const* feature = nullptr)
       : Value(std::move(v))
       , IsPath(isPath)
-      , IsObject(isObject)
       , Target(target)
+      , Feature(feature)
     {
     }
     BT<std::string> Value;
-    ItemIsPath IsPath = ItemIsPath::Yes;
-    ItemIsObject IsObject = ItemIsObject::No;
+    ItemIsPath IsPath = ItemIsPath::No;
     cmGeneratorTarget const* Target = nullptr;
+
+    bool HasFeature() const { return this->Feature != nullptr; }
+
+    BT<std::string> GetFormattedItem(std::string const& path) const
+    {
+      return { (this->Feature != nullptr)
+                 ? this->Feature->GetDecoratedItem(path, this->IsPath)
+                 : path,
+               Value.Backtrace };
+    }
+
+  private:
+    FeatureDescriptor const* Feature = nullptr;
   };
   using ItemVector = std::vector<Item>;
   void AppendValues(std::string& result, std::vector<BT<std::string>>& values);
@@ -237,4 +246,36 @@ private:
   void AddLibraryRuntimeInfo(std::string const& fullPath,
                              const cmGeneratorTarget* target);
   void AddLibraryRuntimeInfo(std::string const& fullPath);
+
+  class FeatureDescriptor
+  {
+  public:
+    FeatureDescriptor() = default;
+    FeatureDescriptor(std::string name, std::string itemFormat);
+    FeatureDescriptor(std::string name, std::string itemPathFormat,
+                      std::string itemNameFormat);
+    FeatureDescriptor(std::string name, std::string prefix,
+                      std::string itemPathFormat, std::string itemNameFormat,
+                      std::string suffix);
+
+    const std::string Name;
+    const bool Supported = false;
+    const std::string Prefix;
+    const std::string Suffix;
+    std::string GetDecoratedItem(std::string const& library,
+                                 ItemIsPath isPath) const;
+    std::string GetDecoratedItem(std::string const& library,
+                                 std::string const& linkItem,
+                                 std::string const& defaultValue,
+                                 ItemIsPath isPath) const;
+
+  private:
+    std::string ItemPathFormat;
+    std::string ItemNameFormat;
+  };
+  std::map<std::string, FeatureDescriptor> LibraryFeatureDescriptors;
+  bool AddLibraryFeature(std::string const& feature);
+  FeatureDescriptor const& GetLibraryFeature(std::string const& feature) const;
+  FeatureDescriptor const* FindLibraryFeature(
+    std::string const& feature) const;
 };

Source/cmGeneratorExpressionNode.cxx

@@ -1198,6 +1198,68 @@ static const struct LinkLanguageAndIdNode : public cmGeneratorExpressionNode
   }
 } linkLanguageAndIdNode;
 
+static const struct LinkLibraryNode : public cmGeneratorExpressionNode
+{
+  LinkLibraryNode() {} // NOLINT(modernize-use-equals-default)
+
+  int NumExpectedParameters() const override { return OneOrMoreParameters; }
+
+  std::string Evaluate(
+    const std::vector<std::string>& parameters,
+    cmGeneratorExpressionContext* context,
+    const GeneratorExpressionContent* content,
+    cmGeneratorExpressionDAGChecker* dagChecker) const override
+  {
+    if (!context->HeadTarget || !dagChecker ||
+        !dagChecker->EvaluatingLinkLibraries()) {
+      reportError(context, content->GetOriginalExpression(),
+                  "$<LINK_LIBRARY:...> may only be used with binary targets "
+                  "to specify link libraries.");
+      return std::string();
+    }
+
+    std::vector<std::string> list;
+    cmExpandLists(parameters.begin(), parameters.end(), list);
+    if (list.empty()) {
+      reportError(
+        context, content->GetOriginalExpression(),
+        "$<LINK_LIBRARY:...> expects a feature name as first argument.");
+      return std::string();
+    }
+    if (list.size() == 1) {
+      // no libraries specified, ignore this genex
+      return std::string();
+    }
+
+    auto const& feature = list.front();
+    const auto LL_BEGIN = cmStrCat("<LINK_LIBRARY:", feature, '>');
+    const auto LL_END = cmStrCat("</LINK_LIBRARY:", feature, '>');
+
+    // filter out $<LINK_LIBRARY:..> tags with same feature
+    // and raise an error for any different feature
+    cm::erase_if(list, [&](const std::string& item) -> bool {
+      return item == LL_BEGIN || item == LL_END;
+    });
+    auto it =
+      std::find_if(list.cbegin() + 1, list.cend(),
+                   [&feature](const std::string& item) -> bool {
+                     return cmHasPrefix(item, "<LINK_LIBRARY:"_s) &&
+                       item.substr(14, item.find('>', 14) - 14) != feature;
+                   });
+    if (it != list.cend()) {
+      reportError(
+        context, content->GetOriginalExpression(),
+        "$<LINK_LIBRARY:...> with different features cannot be nested.");
+      return std::string();
+    }
+
+    list.front() = LL_BEGIN;
+    list.push_back(LL_END);
+
+    return cmJoin(list, ";"_s);
+  }
+} linkLibraryNode;
+
 static const struct HostLinkNode : public cmGeneratorExpressionNode
 {
   HostLinkNode() {} // NOLINT(modernize-use-equals-default)
@@ -2668,6 +2730,7 @@ const cmGeneratorExpressionNode* cmGeneratorExpressionNode::GetNode(
     { "COMPILE_LANGUAGE", &languageNode },
     { "LINK_LANG_AND_ID", &linkLanguageAndIdNode },
     { "LINK_LANGUAGE", &linkLanguageNode },
+    { "LINK_LIBRARY", &linkLibraryNode },
     { "HOST_LINK", &hostLinkNode },
     { "DEVICE_LINK", &deviceLinkNode },
     { "SHELL_PATH", &shellPathNode }

Source/cmGeneratorTarget.cxx

@@ -4625,7 +4625,8 @@ std::vector<BT<std::string>> cmGeneratorTarget::GetLinkOptions(
 }
 
 std::vector<BT<std::string>>& cmGeneratorTarget::ResolveLinkerWrapper(
-  std::vector<BT<std::string>>& result, const std::string& language) const
+  std::vector<BT<std::string>>& result, const std::string& language,
+  bool joinItems) const
 {
   // replace "LINKER:" prefixed elements by actual linker wrapper
   const std::string wrapper(this->Makefile->GetSafeDefinition(
@@ -4684,7 +4685,14 @@ std::vector<BT<std::string>>& cmGeneratorTarget::ResolveLinkerWrapper(
 
     std::vector<BT<std::string>> options = wrapOptions(
       linkerOptions, bt, wrapperFlag, wrapperSep, concatFlagAndArgs);
-    result.insert(entry, options.begin(), options.end());
+    if (joinItems) {
+      result.insert(entry,
+                    cmJoin(cmRange<decltype(options.cbegin())>(
+                             options.cbegin(), options.cend()),
+                           " "_s));
+    } else {
+      result.insert(entry, options.begin(), options.end());
+    }
   }
   return result;
 }
@@ -6377,7 +6385,8 @@ bool cmGeneratorTarget::VerifyLinkItemIsTarget(LinkItemRole role,
   std::string const& str = item.AsStr();
   if (!str.empty() &&
       (str[0] == '-' || str[0] == '$' || str[0] == '`' ||
-       str.find_first_of("/\\") != std::string::npos)) {
+       str.find_first_of("/\\") != std::string::npos ||
+       cmHasPrefix(str, "<LINK_LIBRARY:"_s))) {
     return true;
   }
 

Source/cmGeneratorTarget.h

@@ -513,7 +513,8 @@ public:
     std::string const& config, std::string const& language) const;
 
   std::vector<BT<std::string>>& ResolveLinkerWrapper(
-    std::vector<BT<std::string>>& result, const std::string& language) const;
+    std::vector<BT<std::string>>& result, const std::string& language,
+    bool joinItems = false) const;
 
   void GetStaticLibraryLinkOptions(std::vector<std::string>& result,
                                    const std::string& config,

Source/cmGlobalXCodeGenerator.cxx

@@ -3741,7 +3741,9 @@ void cmGlobalXCodeGenerator::AddDependAndLinkInformation(cmXCodeObject* target)
             }
             libPaths.Add("-framework " + this->XCodeEscapePath(fwName));
           } else {
-            libPaths.Add(this->XCodeEscapePath(cleanPath));
+            libPaths.Add(
+              libName.GetFormattedItem(this->XCodeEscapePath(cleanPath))
+                .Value);
           }
           if ((!libName.Target || libName.Target->IsImported()) &&
               IsLinkPhaseLibraryExtension(libPath)) {

Source/cmLinkLibrariesCommand.cxx

@@ -35,5 +35,7 @@ bool cmLinkLibrariesCommand(std::vector<std::string> const& args,
     mf.AppendProperty("LINK_LIBRARIES", *i);
   }
 
+  mf.CheckProperty("LINK_LIBRARIES");
+
   return true;
 }

Source/cmLinkLineComputer.cxx

@@ -75,14 +75,8 @@ void cmLinkLineComputer::ComputeLinkLibs(
 
     BT<std::string> linkLib;
     if (item.IsPath == cmComputeLinkInformation::ItemIsPath::Yes) {
-      if (item.IsObject == cmComputeLinkInformation::ItemIsObject::Yes) {
-        linkLib.Value += cli.GetObjLinkFileFlag();
-      } else {
-        linkLib.Value += cli.GetLibLinkFileFlag();
-      }
-      linkLib.Value += this->ConvertToOutputFormat(
-        this->ConvertToLinkReference(item.Value.Value));
-      linkLib.Backtrace = item.Value.Backtrace;
+      linkLib = item.GetFormattedItem(this->ConvertToOutputFormat(
+        this->ConvertToLinkReference(item.Value.Value)));
     } else {
       linkLib = item.Value;
     }

Source/cmLinkLineDeviceComputer.cxx

@@ -118,8 +118,10 @@ void cmLinkLineDeviceComputer::ComputeLinkLibraries(
       // can tolerate '.so' or '.dylib' it cannot tolerate '.so.1'.
       if (cmHasLiteralSuffix(item.Value.Value, ".a") ||
           cmHasLiteralSuffix(item.Value.Value, ".lib")) {
-        linkLib.Value += this->ConvertToOutputFormat(
-          this->ConvertToLinkReference(item.Value.Value));
+        linkLib.Value = item
+                          .GetFormattedItem(this->ConvertToOutputFormat(
+                            this->ConvertToLinkReference(item.Value.Value)))
+                          .Value;
       }
     } else if (item.Value == "-framework") {
       // This is the first part of '-framework Name' where the framework
@@ -127,7 +129,7 @@ void cmLinkLineDeviceComputer::ComputeLinkLibraries(
       skipItemAfterFramework = true;
       continue;
     } else if (cmLinkItemValidForDevice(item.Value.Value)) {
-      linkLib.Value += item.Value.Value;
+      linkLib.Value = item.Value.Value;
     }
 
     if (emitted.insert(linkLib.Value).second) {

Source/cmLocalVisualStudio7Generator.cxx

@@ -1294,7 +1294,9 @@ void cmLocalVisualStudio7GeneratorInternals::OutputLibraries(
   for (auto const& lib : libs) {
     if (lib.IsPath == cmComputeLinkInformation::ItemIsPath::Yes) {
       std::string rel = lg->MaybeRelativeToCurBinDir(lib.Value.Value);
-      fout << lg->ConvertToXMLOutputPath(rel) << " ";
+      rel = lg->ConvertToXMLOutputPath(rel);
+      fout << (lib.HasFeature() ? lib.GetFormattedItem(rel).Value : rel)
+           << " ";
     } else if (!lib.Target ||
                lib.Target->GetType() != cmStateEnums::INTERFACE_LIBRARY) {
       fout << lib.Value.Value << " ";

Source/cmMakefile.cxx

@@ -3976,6 +3976,31 @@ std::vector<std::string> cmMakefile::GetPropertyKeys() const
   return this->StateSnapshot.GetDirectory().GetPropertyKeys();
 }
 
+void cmMakefile::CheckProperty(const std::string& prop) const
+{
+  // Certain properties need checking.
+  if (prop == "LINK_LIBRARIES") {
+    if (cmValue value = this->GetProperty(prop)) {
+      // Look for <LINK_LIBRARY:> internal pattern
+      static cmsys::RegularExpression linkLibrary(
+        "(^|;)(</?LINK_LIBRARY:[^;>]*>)(;|$)");
+      if (!linkLibrary.find(value)) {
+        return;
+      }
+
+      // Report an error.
+      this->IssueMessage(
+        MessageType::FATAL_ERROR,
+        cmStrCat(
+          "Property ", prop, " contains the invalid item \"",
+          linkLibrary.match(2), "\". The ", prop,
+          " property may contain the generator-expression "
+          "\"$<LINK_LIBRARY:...>\" "
+          "which may be used to specify how the libraries are linked."));
+    }
+  }
+}
+
 cmTarget* cmMakefile::FindLocalNonAliasTarget(const std::string& name) const
 {
   auto i = this->Targets.find(name);

Source/cmMakefile.h

@@ -787,6 +787,7 @@ public:
   cmValue GetProperty(const std::string& prop, bool chain) const;
   bool GetPropertyAsBool(const std::string& prop) const;
   std::vector<std::string> GetPropertyKeys() const;
+  void CheckProperty(const std::string& prop) const;
 
   //! Initialize a makefile from its parent
   void InitializeFromParent(cmMakefile* parent);

Source/cmTarget.cxx

@@ -1779,69 +1779,93 @@ void cmTarget::InsertPrecompileHeader(BT<std::string> const& entry)
   this->impl->PrecompileHeadersEntries.push_back(entry);
 }
 
-static void cmTargetCheckLINK_INTERFACE_LIBRARIES(const std::string& prop,
-                                                  const std::string& value,
-                                                  cmMakefile* context,
-                                                  bool imported)
+namespace {
+void CheckLinkLibraryPattern(const std::string& property,
+                             const std::string& value, cmMakefile* context)
 {
-  // Look for link-type keywords in the value.
-  static cmsys::RegularExpression keys("(^|;)(debug|optimized|general)(;|$)");
-  if (!keys.find(value)) {
+  // Look for <LINK_LIBRARY:> and </LINK_LIBRARY:> internal tags
+  static cmsys::RegularExpression linkLibrary(
+    "(^|;)(</?LINK_LIBRARY:[^;>]*>)(;|$)");
+  if (!linkLibrary.find(value)) {
     return;
   }
 
+  // Report an error.
+  context->IssueMessage(
+    MessageType::FATAL_ERROR,
+    cmStrCat("Property ", property, " contains the invalid item \"",
+             linkLibrary.match(2), "\". The ", property,
+             " property may contain the generator-expression "
+             "\"$<LINK_LIBRARY:...>\" "
+             "which may be used to specify how the libraries are linked."));
+}
+
+void CheckLINK_INTERFACE_LIBRARIES(const std::string& prop,
+                                   const std::string& value,
+                                   cmMakefile* context, bool imported)
+{
   // Support imported and non-imported versions of the property.
   const char* base = (imported ? "IMPORTED_LINK_INTERFACE_LIBRARIES"
                                : "LINK_INTERFACE_LIBRARIES");
 
-  // Report an error.
-  std::ostringstream e;
-  e << "Property " << prop << " may not contain link-type keyword \""
-    << keys.match(2) << "\".  "
-    << "The " << base << " property has a per-configuration "
-    << "version called " << base << "_<CONFIG> which may be "
-    << "used to specify per-configuration rules.";
-  if (!imported) {
-    e << "  "
-      << "Alternatively, an IMPORTED library may be created, configured "
-      << "with a per-configuration location, and then named in the "
-      << "property value.  "
-      << "See the add_library command's IMPORTED mode for details."
-      << "\n"
-      << "If you have a list of libraries that already contains the "
-      << "keyword, use the target_link_libraries command with its "
-      << "LINK_INTERFACE_LIBRARIES mode to set the property.  "
-      << "The command automatically recognizes link-type keywords and sets "
-      << "the LINK_INTERFACE_LIBRARIES and LINK_INTERFACE_LIBRARIES_DEBUG "
-      << "properties accordingly.";
-  }
-  context->IssueMessage(MessageType::FATAL_ERROR, e.str());
-}
-
-static void cmTargetCheckINTERFACE_LINK_LIBRARIES(const std::string& value,
-                                                  cmMakefile* context)
-{
   // Look for link-type keywords in the value.
   static cmsys::RegularExpression keys("(^|;)(debug|optimized|general)(;|$)");
-  if (!keys.find(value)) {
-    return;
+  if (keys.find(value)) {
+    // Report an error.
+    std::ostringstream e;
+    e << "Property " << prop << " may not contain link-type keyword \""
+      << keys.match(2) << "\".  "
+      << "The " << base << " property has a per-configuration "
+      << "version called " << base << "_<CONFIG> which may be "
+      << "used to specify per-configuration rules.";
+    if (!imported) {
+      e << "  "
+        << "Alternatively, an IMPORTED library may be created, configured "
+        << "with a per-configuration location, and then named in the "
+        << "property value.  "
+        << "See the add_library command's IMPORTED mode for details."
+        << "\n"
+        << "If you have a list of libraries that already contains the "
+        << "keyword, use the target_link_libraries command with its "
+        << "LINK_INTERFACE_LIBRARIES mode to set the property.  "
+        << "The command automatically recognizes link-type keywords and sets "
+        << "the LINK_INTERFACE_LIBRARIES and LINK_INTERFACE_LIBRARIES_DEBUG "
+        << "properties accordingly.";
+    }
+    context->IssueMessage(MessageType::FATAL_ERROR, e.str());
   }
 
-  // Report an error.
-  std::ostringstream e;
+  CheckLinkLibraryPattern(base, value, context);
+}
+
+void CheckLINK_LIBRARIES(const std::string& value, cmMakefile* context)
+{
+  CheckLinkLibraryPattern("LINK_LIBRARIES", value, context);
+}
 
-  e << "Property INTERFACE_LINK_LIBRARIES may not contain link-type "
-       "keyword \""
-    << keys.match(2)
-    << "\".  The INTERFACE_LINK_LIBRARIES "
-       "property may contain configuration-sensitive generator-expressions "
-       "which may be used to specify per-configuration rules.";
+void CheckINTERFACE_LINK_LIBRARIES(const std::string& value,
+                                   cmMakefile* context)
+{
+  // Look for link-type keywords in the value.
+  static cmsys::RegularExpression keys("(^|;)(debug|optimized|general)(;|$)");
+  if (keys.find(value)) {
+    // Report an error.
+    std::ostringstream e;
+
+    e << "Property INTERFACE_LINK_LIBRARIES may not contain link-type "
+         "keyword \""
+      << keys.match(2)
+      << "\".  The INTERFACE_LINK_LIBRARIES "
+         "property may contain configuration-sensitive generator-expressions "
+         "which may be used to specify per-configuration rules.";
+
+    context->IssueMessage(MessageType::FATAL_ERROR, e.str());
+  }
 
-  context->IssueMessage(MessageType::FATAL_ERROR, e.str());
+  CheckLinkLibraryPattern("INTERFACE_LINK_LIBRARIES", value, context);
 }
 
-static void cmTargetCheckIMPORTED_GLOBAL(const cmTarget* target,
-                                         cmMakefile* context)
+void CheckIMPORTED_GLOBAL(const cmTarget* target, cmMakefile* context)
 {
   const auto& targets = context->GetOwnedImportedTargets();
   auto it =
@@ -1857,6 +1881,7 @@ static void cmTargetCheckIMPORTED_GLOBAL(const cmTarget* target,
     context->IssueMessage(MessageType::FATAL_ERROR, e.str());
   }
 }
+}
 
 void cmTarget::CheckProperty(const std::string& prop,
                              cmMakefile* context) const
@@ -1864,22 +1889,23 @@ void cmTarget::CheckProperty(const std::string& prop,
   // Certain properties need checking.
   if (cmHasLiteralPrefix(prop, "LINK_INTERFACE_LIBRARIES")) {
     if (cmValue value = this->GetProperty(prop)) {
-      cmTargetCheckLINK_INTERFACE_LIBRARIES(prop, *value, context, false);
+      CheckLINK_INTERFACE_LIBRARIES(prop, *value, context, false);
     }
-  }
-  if (cmHasLiteralPrefix(prop, "IMPORTED_LINK_INTERFACE_LIBRARIES")) {
+  } else if (cmHasLiteralPrefix(prop, "IMPORTED_LINK_INTERFACE_LIBRARIES")) {
     if (cmValue value = this->GetProperty(prop)) {
-      cmTargetCheckLINK_INTERFACE_LIBRARIES(prop, *value, context, true);
+      CheckLINK_INTERFACE_LIBRARIES(prop, *value, context, true);
     }
-  }
-  if (prop == "INTERFACE_LINK_LIBRARIES") {
+  } else if (prop == "LINK_LIBRARIES") {
     if (cmValue value = this->GetProperty(prop)) {
-      cmTargetCheckINTERFACE_LINK_LIBRARIES(*value, context);
+      CheckLINK_LIBRARIES(*value, context);
     }
-  }
-  if (prop == "IMPORTED_GLOBAL") {
+  } else if (prop == "INTERFACE_LINK_LIBRARIES") {
+    if (cmValue value = this->GetProperty(prop)) {
+      CheckINTERFACE_LINK_LIBRARIES(*value, context);
+    }
+  } else if (prop == "IMPORTED_GLOBAL") {
     if (this->IsImported()) {
-      cmTargetCheckIMPORTED_GLOBAL(this, context);
+      CheckIMPORTED_GLOBAL(this, context);
     }
   }
 }

Source/cmTargetLinkLibrariesCommand.cxx

@@ -318,6 +318,9 @@ bool cmTargetLinkLibrariesCommand(std::vector<std::string> const& args,
     target->SetProperty("LINK_INTERFACE_LIBRARIES", "");
   }
 
+  target->CheckProperty("LINK_LIBRARIES", &mf);
+  target->CheckProperty("INTERFACE_LINK_LIBRARIES", &mf);
+
   return true;
 }
 

Source/cmVisualStudio10TargetGenerator.cxx

@@ -3677,7 +3677,8 @@ bool cmVisualStudio10TargetGenerator::ComputeCudaLinkOptions(
           this->LocalGenerator->MaybeRelativeToCurBinDir(l.Value.Value);
         ConvertToWindowsSlash(path);
         if (!cmVS10IsTargetsFile(l.Value.Value)) {
-          libVec.push_back(path);
+          libVec.push_back(l.HasFeature() ? l.GetFormattedItem(path).Value
+                                          : path);
         }
       } else {
         libVec.push_back(l.Value.Value);
@@ -4315,7 +4316,8 @@ void cmVisualStudio10TargetGenerator::AddLibraries(
       if (cmVS10IsTargetsFile(l.Value.Value)) {
         vsTargetVec.push_back(path);
       } else {
-        libVec.push_back(path);
+        libVec.push_back(l.HasFeature() ? l.GetFormattedItem(path).Value
+                                        : path);
       }
     } else if (!l.Target ||
                l.Target->GetType() != cmStateEnums::INTERFACE_LIBRARY) {

Tests/RunCMake/CMakeLists.txt

@@ -312,6 +312,7 @@ add_RunCMake_test(GenEx-LINK_LANGUAGE)
 add_RunCMake_test(GenEx-LINK_LANG_AND_ID)
 add_RunCMake_test(GenEx-HOST_LINK)
 add_RunCMake_test(GenEx-DEVICE_LINK)
+add_RunCMake_test(GenEx-LINK_LIBRARY)
 add_RunCMake_test(GenEx-TARGET_FILE -DLINKER_SUPPORTS_PDB=${LINKER_SUPPORTS_PDB})
 add_RunCMake_test(GenEx-GENEX_EVAL)
 add_RunCMake_test(GenEx-TARGET_RUNTIME_DLLS)
@@ -652,6 +653,17 @@ add_RunCMake_test(target_link_libraries)
 add_RunCMake_test(target_link_libraries-ALIAS)
 add_RunCMake_test(target_link_libraries-LINK_LANGUAGE)
 add_RunCMake_test(target_link_libraries-LINK_LANG_AND_ID)
+add_RunCMake_test(target_link_libraries-LINK_LIBRARY -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}
+                                                     -DMINGW=${MINGW}
+                                                     -DMSYS=${MSYS}
+                                                     -DCYGWIN=${CYGWIN}
+                                                     -DCMAKE_C_COMPILER_ID=${CMAKE_C_COMPILER_ID}
+                                                     -DMSVC_VERSION=${MSVC_VERSION}
+                                                     -DCMAKE_SHARED_LIBRARY_PREFIX=${CMAKE_SHARED_LIBRARY_PREFIX}
+                                                     -DCMAKE_SHARED_LIBRARY_SUFFIX=${CMAKE_SHARED_LIBRARY_SUFFIX}
+                                                     -DCMAKE_IMPORT_LIBRARY_PREFIX=${CMAKE_IMPORT_LIBRARY_PREFIX}
+                                                     -DCMAKE_IMPORT_LIBRARY_SUFFIX=${CMAKE_IMPORT_LIBRARY_SUFFIX}
+                                                     -DCMAKE_LINK_LIBRARY_FLAG=${CMAKE_LINK_LIBRARY_FLAG})
 add_RunCMake_test(add_link_options -DCMAKE_C_COMPILER_ID=${CMAKE_C_COMPILER_ID})
 add_RunCMake_test(target_link_options -DCMAKE_C_COMPILER_ID=${CMAKE_C_COMPILER_ID}
                                       -DCMake_TEST_CUDA=${CMake_TEST_CUDA})

Tests/RunCMake/GenEx-LINK_LIBRARY/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.18...3.22)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/GenEx-LINK_LIBRARY/RunCMakeTest.cmake

@@ -0,0 +1,25 @@
+include(RunCMake)
+
+run_cmake(add_custom_target)
+run_cmake(add_custom_command)
+run_cmake(add_link_options)
+run_cmake(link_directories)
+run_cmake(target_link_options)
+run_cmake(target_link_directories)
+run_cmake(no-arguments)
+run_cmake(empty-arguments)
+run_cmake(forbidden-arguments)
+run_cmake(bad-feature1)
+run_cmake(bad-feature2)
+run_cmake(bad-feature3)
+run_cmake(bad-feature4)
+run_cmake(bad-feature5)
+run_cmake(bad-feature6)
+run_cmake(bad-feature7)
+run_cmake(feature-not-supported)
+run_cmake(library-ignored)
+run_cmake(compatible-features)
+run_cmake(incompatible-features)
+run_cmake(nested-compatible-features)
+run_cmake(nested-incompatible-features)
+run_cmake(only-targets)

Tests/RunCMake/GenEx-LINK_LIBRARY/add_custom_command-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/add_custom_command-stderr.txt

@@ -0,0 +1,9 @@
+CMake Error at add_custom_command.cmake:[0-9]+ \(add_custom_command\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:feat>
+
+  \$<LINK_LIBRARY:...> may only be used with binary targets to specify link
+  libraries.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/add_custom_command.cmake

@@ -0,0 +1,4 @@
+add_custom_target(drive)
+add_custom_command(TARGET drive PRE_BUILD
+  COMMAND ${CMAKE_COMMAND} -E echo "$<LINK_LIBRARY:feat>"
+)

Tests/RunCMake/GenEx-LINK_LIBRARY/add_custom_target-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/add_custom_target-stderr.txt

@@ -0,0 +1,9 @@
+CMake Error at add_custom_target.cmake:[0-9]+ \(add_custom_target\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:feat>
+
+  \$<LINK_LIBRARY:...> may only be used with binary targets to specify link
+  libraries.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/add_custom_target.cmake

@@ -0,0 +1,3 @@
+add_custom_target(drive
+  COMMAND ${CMAKE_COMMAND} -E echo "$<LINK_LIBRARY:feat>"
+)

Tests/RunCMake/GenEx-LINK_LIBRARY/add_link_options-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/add_link_options-stderr.txt

@@ -0,0 +1,9 @@
+CMake Error at add_link_options.cmake:[0-9]+ \(add_link_options\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:feat>
+
+  \$<LINK_LIBRARY:...> may only be used with binary targets to specify link
+  libraries.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/add_link_options.cmake

@@ -0,0 +1,5 @@
+enable_language(C)
+
+add_link_options("$<LINK_LIBRARY:feat>")
+
+add_library(empty SHARED empty.c)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature1-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature1-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at bad-feature1.cmake:[0-9]+ \(add_library\):
+  Feature 'bad_feat', specified through generator-expression
+  '\$<LINK_LIBRARY>' to link target 'lib', is not supported for the 'C' link
+  language.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature1.cmake

@@ -0,0 +1,6 @@
+enable_language(C)
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:bad_feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature2-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature2-stderr.txt

@@ -0,0 +1,5 @@
+CMake Error at bad-feature2.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified through generator-expression '\$<LINK_LIBRARY>' to
+  link target 'lib', is not defined for the 'C' link language.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature2.cmake

@@ -0,0 +1,8 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature3-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature3-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at bad-feature3.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified by variable 'CMAKE_C_LINK_USING_feat', is
+  malformed \("<LIBRARY>", "<LIB_ITEM>", or "<LINK_ITEM>" patterns are
+  missing\) and cannot be used to link target 'lib'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature3.cmake

@@ -0,0 +1,9 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat "")
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature4-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature4-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at bad-feature4.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified by variable 'CMAKE_C_LINK_USING_feat', is
+  malformed \("<LIBRARY>", "<LIB_ITEM>", or "<LINK_ITEM>" patterns are
+  missing\) and cannot be used to link target 'lib'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature4.cmake

@@ -0,0 +1,9 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat "-opt")
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature5-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature5-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at bad-feature5.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified by variable 'CMAKE_C_LINK_USING_feat', is
+  malformed \(wrong number of elements\) and cannot be used to link target
+  'lib'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature5.cmake

@@ -0,0 +1,9 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat "-prefix" "<LIBRARY>")
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature6-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature6-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at bad-feature6.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified by variable 'CMAKE_C_LINK_USING_feat', is
+  malformed \("<LIBRARY>", "<LIB_ITEM>", or "<LINK_ITEM>" patterns are missing
+  for "PATH{}" alternative\) and cannot be used to link target 'lib'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature6.cmake

@@ -0,0 +1,9 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat "PATH{}NAME{<LIBRARY>}")
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature7-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature7-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at bad-feature7.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified by variable 'CMAKE_C_LINK_USING_feat', is
+  malformed \("<LIBRARY>", "<LIB_ITEM>", or "<LINK_ITEM>" patterns are missing
+  for "NAME{}" alternative\) and cannot be used to link target 'lib'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/bad-feature7.cmake

@@ -0,0 +1,9 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat "NAME{}PATH{<LIBRARY>}")
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/compatible-features.cmake

@@ -0,0 +1,15 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat1_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat1 "<LIBRARY>")
+
+set(CMAKE_C_LINK_USING_feat2_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat2 "<LIBRARY>")
+
+add_library(dep1 SHARED empty.c)
+
+add_library(dep2 SHARED empty.c)
+target_link_libraries(dep2 PRIVATE "$<LINK_LIBRARY:feat1,dep1>")
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat2,dep1,dep2>")

Tests/RunCMake/GenEx-LINK_LIBRARY/empty-arguments-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/empty-arguments-stderr.txt

@@ -0,0 +1,8 @@
+CMake Error at empty-arguments.cmake:[0-9]+ \(target_link_libraries\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:,>
+
+  \$<LINK_LIBRARY:...> expects a feature name as first argument.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/empty-arguments.cmake

@@ -0,0 +1,4 @@
+enable_language(C)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:,>")

Tests/RunCMake/GenEx-LINK_LIBRARY/feature-not-supported-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/feature-not-supported-stderr.txt

@@ -0,0 +1,5 @@
+CMake Error at feature-not-supported.cmake:[0-9]+ \(add_library\):
+  Feature 'feat', specified through generator-expression '\$<LINK_LIBRARY>' to
+  link target 'lib', is not supported for the 'C' link language.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/feature-not-supported.cmake

@@ -0,0 +1,9 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED FALSE)
+set(CMAKE_C_LINK_USING_feat "<LIBRARY>")
+
+add_library(dep SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/forbidden-arguments-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/forbidden-arguments-stderr.txt

@@ -0,0 +1,16 @@
+CMake Error at forbidden-arguments.cmake:[0-9]+ \(link_libraries\):
+  Property LINK_LIBRARIES contains the invalid item "<LINK_LIBRARY:feat>".
+  The LINK_LIBRARIES property may contain the generator-expression
+  "\$<LINK_LIBRARY:...>" which may be used to specify how the libraries are
+  linked.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
+
+
+CMake Error at forbidden-arguments.cmake:[0-9]+ \(target_link_libraries\):
+  Property LINK_LIBRARIES contains the invalid item "<LINK_LIBRARY:feat>".
+  The LINK_LIBRARIES property may contain the generator-expression
+  "\$<LINK_LIBRARY:...>" which may be used to specify how the libraries are
+  linked.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/forbidden-arguments.cmake

@@ -0,0 +1,6 @@
+enable_language(C)
+
+link_libraries(<LINK_LIBRARY:feat> foo </LINK_LIBRARY:feat>)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE <LINK_LIBRARY:feat> foo </LINK_LIBRARY:feat>)

Tests/RunCMake/GenEx-LINK_LIBRARY/incompatible-features-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/incompatible-features-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at incompatible-features.cmake:[0-9]+ \(add_library\):
+  Impossible to link target 'lib' because the link item 'dep1', specified
+  with the feature 'feat1', has already occurred with the feature 'feat2',
+  which is not allowed.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/incompatible-features.cmake

@@ -0,0 +1,15 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat1_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat1 "<LIBRARY>")
+
+set(CMAKE_C_LINK_USING_feat2_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat2 "<LIBRARY>")
+
+add_library(dep1 SHARED empty.c)
+
+add_library(dep2 SHARED empty.c)
+target_link_libraries(dep2 PUBLIC "$<LINK_LIBRARY:feat1,dep1>")
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat2,dep1,dep2>")

Tests/RunCMake/GenEx-LINK_LIBRARY/library-ignored-stderr.txt

@@ -0,0 +1,14 @@
+CMake Warning \(dev\) at library-ignored.cmake:[0-9]+ \(add_library\):
+  The feature 'feat', specified as part of a generator-expression
+  '\$<LINK_LIBRARY:feat>', will not be applied to the INTERFACE library
+  'front'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
+This warning is for project developers.  Use -Wno-dev to suppress it.
+
+CMake Warning \(dev\) at library-ignored.cmake:[0-9]+ \(add_library\):
+  The feature 'feat', specified as part of a generator-expression
+  '\$<LINK_LIBRARY:feat>', will not be applied to the OBJECT library 'dep'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
+This warning is for project developers.  Use -Wno-dev to suppress it.

Tests/RunCMake/GenEx-LINK_LIBRARY/library-ignored.cmake

@@ -0,0 +1,15 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat "<LIBRARY>")
+
+add_library(dep OBJECT empty.c)
+
+add_library(lib SHARED empty.c)
+
+add_library(front INTERFACE)
+target_link_libraries(front INTERFACE lib)
+
+
+add_library(lib2 SHARED empty.c)
+target_link_libraries(lib2 PRIVATE "$<LINK_LIBRARY:feat,front,dep>")

Tests/RunCMake/GenEx-LINK_LIBRARY/link_directories-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/link_directories-stderr.txt

@@ -0,0 +1,9 @@
+CMake Error at link_directories.cmake:[0-9]+ \(link_directories\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:feat>
+
+  \$<LINK_LIBRARY:...> may only be used with binary targets to specify link
+  libraries.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/link_directories.cmake

@@ -0,0 +1,5 @@
+enable_language(C)
+
+link_directories("$<LINK_LIBRARY:feat>")
+
+add_library(empty SHARED empty.c)

Tests/RunCMake/GenEx-LINK_LIBRARY/nested-compatible-features.cmake

@@ -0,0 +1,11 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat1_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat1 "<LIBRARY>")
+
+add_library(dep1 SHARED empty.c)
+
+add_library(dep2 SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat1,dep1,$<LINK_LIBRARY:feat1,dep2>>")

Tests/RunCMake/GenEx-LINK_LIBRARY/nested-incompatible-features-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/nested-incompatible-features-stderr.txt

@@ -0,0 +1,8 @@
+CMake Error at nested-incompatible-features.cmake:[0-9]+ \(target_link_libraries\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:feat2,dep1,\$<LINK_LIBRARY:feat1,dep2>>
+
+  \$<LINK_LIBRARY:...> with different features cannot be nested.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/nested-incompatible-features.cmake

@@ -0,0 +1,14 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat1_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat1 "<LIBRARY>")
+
+set(CMAKE_C_LINK_USING_feat2_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat2 "<LIBRARY>")
+
+add_library(dep1 SHARED empty.c)
+
+add_library(dep2 SHARED empty.c)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY:feat2,dep1,$<LINK_LIBRARY:feat1,dep2>>")

Tests/RunCMake/GenEx-LINK_LIBRARY/no-arguments-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/no-arguments-stderr.txt

@@ -0,0 +1,8 @@
+CMake Error at no-arguments.cmake:[0-9]+ \(target_link_libraries\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY>
+
+  \$<LINK_LIBRARY> expression requires at least one parameter.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/no-arguments.cmake

@@ -0,0 +1,4 @@
+enable_language(C)
+
+add_library(lib SHARED empty.c)
+target_link_libraries(lib PRIVATE "$<LINK_LIBRARY>")

Tests/RunCMake/GenEx-LINK_LIBRARY/only-targets-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/only-targets-stderr.txt

@@ -0,0 +1,13 @@
+CMake Error at only-targets.cmake:[0-9]+ \(target_link_libraries\):
+  Target "lib2" has LINK_LIBRARIES_ONLY_TARGETS enabled, but it links to:
+
+    external
+
+  which is not a target.  Possible reasons include:
+
+    \* There is a typo in the target name.
+    \* A find_package call is missing for an IMPORTED target.
+    \* An ALIAS target is missing.
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/only-targets.cmake

@@ -0,0 +1,16 @@
+enable_language(C)
+
+set(CMAKE_C_LINK_USING_feat1_SUPPORTED TRUE)
+set(CMAKE_C_LINK_USING_feat1 "<LIBRARY>")
+
+set(CMAKE_LINK_LIBRARIES_ONLY_TARGETS 1)
+
+add_library(dep1 SHARED empty.c)
+
+add_library(lib1 SHARED empty.c)
+# accepted
+target_link_libraries(lib1 PRIVATE "$<LINK_LIBRARY:feat1,dep1>")
+
+add_library(lib2 SHARED empty.c)
+# invalid
+target_link_libraries(lib2 PRIVATE "$<LINK_LIBRARY:feat1,external>")

Tests/RunCMake/GenEx-LINK_LIBRARY/target_link_directories-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/target_link_directories-stderr.txt

@@ -0,0 +1,9 @@
+CMake Error at target_link_directories.cmake:[0-9]+ \(target_link_directories\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:feat>
+
+  \$<LINK_LIBRARY:...> may only be used with binary targets to specify link
+  libraries.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/target_link_directories.cmake

@@ -0,0 +1,4 @@
+enable_language(C)
+
+add_library(empty SHARED empty.c)
+target_link_directories(empty PRIVATE "$<LINK_LIBRARY:feat>")

Tests/RunCMake/GenEx-LINK_LIBRARY/target_link_options-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/GenEx-LINK_LIBRARY/target_link_options-stderr.txt

@@ -0,0 +1,9 @@
+CMake Error at target_link_options.cmake:[0-9]+ \(target_link_options\):
+  Error evaluating generator expression:
+
+    \$<LINK_LIBRARY:FEAT>
+
+  \$<LINK_LIBRARY:...> may only be used with binary targets to specify link
+  libraries.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/GenEx-LINK_LIBRARY/target_link_options.cmake

@@ -0,0 +1,4 @@
+enable_language(C)
+
+add_library(empty SHARED empty.c)
+target_link_options(empty PRIVATE $<LINK_LIBRARY:FEAT>)

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.1...3.22)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake NO_POLICY_SCOPE)

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/LINK_LIBRARY-group1-check.cmake

@@ -0,0 +1,4 @@
+
+if (NOT actual_stdout MATCHES "(/|-)-LIBFLAG.*${LINK_SHARED_LIBRARY_PREFIX}base1${LINK_SHARED_LIBRARY_SUFFIX}\"? +\"?(/|-)-LIBFLAG.*${LINK_SHARED_LIBRARY_PREFIX}base2${LINK_SHARED_LIBRARY_SUFFIX}")
+  set (RunCMake_TEST_FAILED "Not found expected '--LIBFLAG<base1> --LIBFLAG<base2>'.")
+endif()

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/LINK_LIBRARY-group1-result.txt

@@ -0,0 +1 @@
+.*

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/LINK_LIBRARY-group2-check.cmake

@@ -0,0 +1,4 @@
+
+if (NOT actual_stdout MATCHES "(/|-)-PREFIXGROUP\"? +\"?(/|-)-LIBGROUP.*${LINK_SHARED_LIBRARY_PREFIX}base1${LINK_SHARED_LIBRARY_SUFFIX}\"? +\"?(/|-)-LIBGROUP.*${LINK_SHARED_LIBRARY_PREFIX}base2${LINK_SHARED_LIBRARY_SUFFIX}\"? +\"?(/|-)-SUFFIXGROUP")
+  set (RunCMake_TEST_FAILED "Not found expected '--PREFIXGROUP --LIBGROUP<base1> --LIBGROUP<base2> --SUFFIXGROUP'.")
+endif()

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/LINK_LIBRARY-group2-result.txt

@@ -0,0 +1 @@
+.*

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/LINK_LIBRARY-link-items1-check.cmake

@@ -0,0 +1,4 @@
+
+if (NOT actual_stdout MATCHES "(/|-)-PREFIXGROUP\"? +\"?.*${LINK_SHARED_LIBRARY_PREFIX}base1${LINK_SHARED_LIBRARY_SUFFIX}\"? +\"?${CMAKE_LINK_LIBRARY_FLAG}other${LINK_EXTERN_LIBRARY_SUFFIX}\"? +\"?(/|-)-SUFFIXGROUP")
+  set (RunCMake_TEST_FAILED "Not found expected '--PREFIXGROUP <base1> <other> --SUFFIXGROUP'.")
+endif()

Tests/RunCMake/target_link_libraries-LINK_LIBRARY/LINK_LIBRARY-link-items1-result.txt

@@ -0,0 +1 @@
+.*