ENH: Make CMAKE_MINIMUM_REQUIRED command FATAL_ERROR option implicit (always on). Accept but ignore the existing option.

Source/cmCMakeMinimumRequired.cxx

@@ -25,7 +25,6 @@ bool cmCMakeMinimumRequired
   // Process arguments.
   std::string version_string;
   bool doing_version = false;
-  bool fatal_error = false;
   for(unsigned int i=0; i < args.size(); ++i)
     {
     if(args[i] == "VERSION")
@@ -40,7 +39,6 @@ bool cmCMakeMinimumRequired
         return false;
         }
       doing_version = false;
-      fatal_error = true;
       }
     else if(doing_version)
       {
@@ -101,24 +99,13 @@ bool cmCMakeMinimumRequired
     {
     // The current version is too low.
     cmOStringStream e;
-    if(!fatal_error)
-      {
-      e << "WARNING: ";
-      }
     e << "This project requires version " << version_string.c_str()
       << " of CMake.  "
       << "You are running version "
       << current_major << "." << current_minor << "." << current_patch
       << ".\n";
-    if(fatal_error)
-      {
-      cmSystemTools::Error(e.str().c_str());
-      cmSystemTools::SetFatalErrorOccured();
-      }
-    else
-      {
-      cmSystemTools::Message(e.str().c_str());
-      }
+    cmSystemTools::Error(e.str().c_str());
+    cmSystemTools::SetFatalErrorOccured();
     }
 
   // set the policy version as well

Source/cmCMakeMinimumRequired.h

@@ -66,12 +66,13 @@ public:
   virtual const char* GetFullDocumentation()
     {
     return
-      "  cmake_minimum_required(VERSION versionNumber [FATAL_ERROR])\n"
-      "Let cmake know that the project requires a certain version of a "
-      "cmake, or newer.  CMake will also try to be backwards compatible to "
-      "the version of cmake specified, if a newer version of cmake is "
-      "running.  If FATAL_ERROR is given then failure to meet the "
-      "requirements will be considered an error instead of a warning.";
+      "  cmake_minimum_required(VERSION major[.minor[.patch]]\n"
+      "                         [FATAL_ERROR])\n"
+      "If the current version of CMake is lower than that required "
+      "it will stop processing the project and report an error.\n"
+      "The FATAL_ERROR option is accepted but ignored.  It is left from "
+      "CMake versions 2.4 and lower in which failure to meet the minimum "
+      "version was a warning by default.";
     }
   
   cmTypeMacro(cmCMakeMinimumRequired, cmCommand);