ENH: put error checking for missing linker languages

Source/cmLocalGenerator.cxx

@@ -598,6 +598,12 @@ void cmLocalGenerator::CreateCustomTargetsAndCommands(std::set<cmStdString> cons
       case cmTarget::EXECUTABLE: 
         {
         const char* llang = target.GetLinkerLanguage(this->GetGlobalGenerator());
+        if(!llang)
+          {
+          cmSystemTools::Error("CMake can not determine linker language for target:",
+                               target.GetName());
+          return;
+          }
         // if the language is not in the set lang then create custom
         // commands to build the target
         if(lang.count(llang) == 0)
@@ -988,6 +994,12 @@ void cmLocalGenerator::GetTargetFlags(std::string& linkLibs,
         linkFlags += " ";
         } 
       const char* linkLanguage = target.GetLinkerLanguage(this->GetGlobalGenerator());
+      if(!linkLanguage)
+        {
+        cmSystemTools::Error("CMake can not determine linker language for target:",
+                             target.GetName());
+        return;
+        }
       std::string langVar = "CMAKE_";
       langVar += linkLanguage;
       std::string flagsVar = langVar + "_FLAGS";
@@ -1056,6 +1068,12 @@ void cmLocalGenerator::OutputLinkLibraries(std::ostream& fout,
   buildType = cmSystemTools::UpperCase(buildType);
 
   const char* linkLanguage = tgt.GetLinkerLanguage(this->GetGlobalGenerator());
+  if(!linkLanguage)
+    {
+    cmSystemTools::Error("CMake can not determine linker language for target:",
+                         tgt.GetName());
+    return;
+    }
   std::string runTimeFlagVar = "CMAKE_SHARED_LIBRARY_RUNTIME_";
   runTimeFlagVar += linkLanguage;
   runTimeFlagVar += "_FLAG";

Source/cmLocalUnixMakefileGenerator.cxx

@@ -876,6 +876,12 @@ void cmLocalUnixMakefileGenerator::OutputSharedLibraryRule(std::ostream& fout,
                                                            const cmTarget &t)
 {
   const char* linkLanguage = t.GetLinkerLanguage(this->GetGlobalGenerator());
+  if(!linkLanguage)
+    {
+    cmSystemTools::Error("CMake can not determine linker language target:",
+                         t.GetName());
+    return;
+    }
   std::string createRule = "CMAKE_";
   createRule += linkLanguage;
   createRule += "_CREATE_SHARED_LIBRARY";
@@ -922,6 +928,12 @@ void cmLocalUnixMakefileGenerator::OutputModuleLibraryRule(std::ostream& fout,
                                                       const cmTarget &t)
 {
   const char* linkLanguage = t.GetLinkerLanguage(this->GetGlobalGenerator());
+  if(!linkLanguage)
+    {
+    cmSystemTools::Error("CMake can not determine linker language for target:",
+                        t.GetName());
+    return;
+    }
   std::string createRule = "CMAKE_";
   createRule += linkLanguage;
   createRule += "_CREATE_SHARED_MODULE";
@@ -954,6 +966,12 @@ void cmLocalUnixMakefileGenerator::OutputStaticLibraryRule(std::ostream& fout,
                                                       const cmTarget &t)
 {
   const char* linkLanguage = t.GetLinkerLanguage(this->GetGlobalGenerator());
+  if(!linkLanguage)
+    {
+    cmSystemTools::Error("CMake can not determine linker language for target:",
+                         t.GetName());
+    return;
+    }
   std::string createRule = "CMAKE_";
   createRule += linkLanguage;
   createRule += "_CREATE_STATIC_LIBRARY";
@@ -1034,7 +1052,12 @@ void cmLocalUnixMakefileGenerator::OutputExecutableRule(std::ostream& fout,
     linkFlags += " ";
     }
   const char* linkLanguage = t.GetLinkerLanguage(this->GetGlobalGenerator());
-
+  if(!linkLanguage)
+    {
+    cmSystemTools::Error("CMake can not determine linker language for target:",
+                         t.GetName());
+    return;
+    }
   std::string langVar = "CMAKE_";
   langVar += linkLanguage;
   

Source/cmLocalVisualStudio6Generator.cxx

@@ -1065,6 +1065,12 @@ void cmLocalVisualStudio6Generator::WriteDSPHeader(std::ostream& fout, const cha
        target.GetType() <= cmTarget::MODULE_LIBRARY)
       {
       const char* linkLanguage = target.GetLinkerLanguage(this->GetGlobalGenerator());
+      if(!linkLanguage)
+        {
+        cmSystemTools::Error("CMake can not determine linker language for target:",
+                             target.GetName());
+        return;
+        }
       // if CXX is on and the target contains cxx code then add the cxx flags
       std::string baseFlagVar = "CMAKE_";
       baseFlagVar += linkLanguage;

Source/cmLocalVisualStudio7Generator.cxx

@@ -329,6 +329,12 @@ void cmLocalVisualStudio7Generator::WriteConfiguration(std::ostream& fout,
   if(strcmp(configType, "10") != 0)
     {
     const char* linkLanguage = target.GetLinkerLanguage(this->GetGlobalGenerator());
+    if(!linkLanguage)
+      {
+      cmSystemTools::Error("CMake can not determine linker language for target:",
+                           target.GetName());
+      return;
+      }
     std::string baseFlagVar = "CMAKE_";
     baseFlagVar += linkLanguage;
     baseFlagVar += "_FLAGS";
@@ -629,6 +635,12 @@ void cmLocalVisualStudio7Generator::OutputBuildTool(std::ostream& fout,
         fout << "\t\t\t\tGenerateDebugInformation=\"TRUE\"\n";
         }
       const char* linkLanguage = target.GetLinkerLanguage(this->GetGlobalGenerator());
+      if(!linkLanguage)
+        {
+        cmSystemTools::Error("CMake can not determine linker language for target:",
+                             target.GetName());
+        return;
+        }
       std::string stackVar = "CMAKE_";
       stackVar += linkLanguage;
       stackVar += "_STACK_SIZE";
@@ -697,8 +709,14 @@ void cmLocalVisualStudio7Generator::OutputBuildTool(std::ostream& fout,
         {      
         fout << "\t\t\t\tSubSystem=\"1\"\n";
         } 
-      const char* linkLanguage = target.GetLinkerLanguage(this->GetGlobalGenerator());
-      std::string stackVar = "CMAKE_";
+      const char* linkLanguage = target.GetLinkerLanguage(this->GetGlobalGenerator()); 
+      if(!linkLanguage)
+        {
+        cmSystemTools::Error("CMake can not determine linker language for target:",
+                             target.GetName());
+        return;
+        }
+     std::string stackVar = "CMAKE_";
       stackVar += linkLanguage;
       stackVar += "_STACK_SIZE";
       const char* stackVal = m_Makefile->GetDefinition(stackVar.c_str());