ENH: Updated exporting and importing of targets to support libraries and configurations.

  - Created cmExportFileGenerator hierarchy to implement export file generation
  - Installed exports use per-config import files loaded by a central one.
  - Include soname of shared libraries in import information
  - Renamed PREFIX to NAMESPACE in INSTALL(EXPORT) and EXPORT() commands
  - Move addition of CMAKE_INSTALL_PREFIX to destinations to install generators
  - Import files compute the installation prefix relative to their location when loaded
  - Add mapping of importer configurations to importee configurations
  - Rename IMPORT targets to IMPORTED targets to distinguish from windows import libraries
  - Scope IMPORTED targets within directories to isolate them
  - Place all properties created by import files in the IMPORTED namespace
  - Document INSTALL(EXPORT) and EXPORT() commands.
  - Document IMPORTED signature of add_executable and add_library
  - Enable finding of imported targets in cmComputeLinkDepends

1 files changed, 52 insertions, 4 deletions

diff --git a/Source/cmAddExecutableCommand.cxx b/Source/cmAddExecutableCommand.cxx
index 9914e17..cea12bc 100644
--- a/Source/cmAddExecutableCommand.cxx
+++ b/Source/cmAddExecutableCommand.cxx
@@ -51,7 +51,7 @@ bool cmAddExecutableCommand
       ++s;
       excludeFromAll = true;
       }
-    else if(*s == "IMPORT")
+    else if(*s == "IMPORTED")
      {
      ++s;
      importTarget = true;
@@ -61,12 +61,60 @@ bool cmAddExecutableCommand
       break;
       }
     }
-    
-  if (importTarget)
+
+  // Special modifiers are not allowed with IMPORTED signature.
+  if(importTarget && (use_win32 || use_macbundle || excludeFromAll))
+    {
+    if(use_win32)
+      {
+      this->SetError("may not be given WIN32 for an IMPORTED target.");
+      }
+    else if(use_macbundle)
+      {
+      this->SetError(
+        "may not be given MACOSX_BUNDLE for an IMPORTED target.");
+      }
+    else // if(excludeFromAll)
+      {
+      this->SetError(
+        "may not be given EXCLUDE_FROM_ALL for an IMPORTED target.");
+      }
+    return false;
+    }
+
+  // Check for an existing target with this name.
+  cmTarget* existing = this->Makefile->FindTargetToUse(exename.c_str());
+  if(importTarget)
     {
-    this->Makefile->AddNewTarget(cmTarget::EXECUTABLE, exename.c_str(), true);
+    // Make sure the target does not already exist.
+    if(existing)
+      {
+      cmOStringStream e;
+      e << "cannot create imported target \"" << exename
+        << "\" because another target with the same name already exists.";
+      this->SetError(e.str().c_str());
+      return false;
+      }
+
+    // Create the imported target.
+    this->Makefile->AddImportedTarget(exename.c_str(), cmTarget::EXECUTABLE);
     return true;
     }
+  else
+    {
+    // Make sure the target does not conflict with an imported target.
+    // This should really enforce global name uniqueness for targets
+    // built within the project too, but that may break compatiblity
+    // with projects in which it was accidentally working.
+    if(existing && existing->IsImported())
+      {
+      cmOStringStream e;
+      e << "cannot create target \"" << exename
+        << "\" because an imported target with the same name already exists.";
+      this->SetError(e.str().c_str());
+      return false;
+      }
+    }
 
   if (s == args.end())
     {