try_compile: Allow only languages loaded in caller (#11469)

During a try_compile cmGlobalGenerator::EnableLanguage uses results from
the outer project.  Reject attempts to enable languages in the test
project that are not "ready" in the outer project.  Mark a language as
"ready" when all its information has been loaded and we are ready to
generate build rules.

This also avoids infinite recursion introduced by commit 295b5b60 (Honor
CMAKE_USER_MAKE_RULES_OVERRIDE in try_compile, 2010-06-29) for projects
that set CMAKE_USER_MAKE_RULES_OVERRIDE to a file that uses try_compile.
The file is loaded along with the information for a given langauge so
the language is not yet "ready".

1 files changed, 4 insertions, 1 deletions

diff --git a/Source/cmGlobalGenerator.h b/Source/cmGlobalGenerator.h
index 878be11..26690af 100644
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@@ -78,7 +78,8 @@ public:
   /**
    * Try to determine system infomation, get it from another generator
    */
-  virtual void EnableLanguagesFromGenerator(cmGlobalGenerator *gen);
+  virtual void EnableLanguagesFromGenerator(cmGlobalGenerator *gen,
+                                            cmMakefile* mf);
 
   /**
    * Try running cmake and building a file. This is used for dynalically
@@ -321,11 +322,13 @@ protected:
   std::map<cmStdString,cmTarget *> TotalTargets;
 
 private:
+  cmMakefile* TryCompileOuterMakefile;
   float FirstTimeProgress;
   // If you add a new map here, make sure it is copied
   // in EnableLanguagesFromGenerator 
   std::map<cmStdString, bool> IgnoreExtensions;
   std::map<cmStdString, bool> LanguageEnabled;
+  std::set<cmStdString> LanguagesReady; // Ready for try_compile
   std::map<cmStdString, cmStdString> OutputExtensions;
   std::map<cmStdString, cmStdString> LanguageToOutputExtension;
   std::map<cmStdString, cmStdString> ExtensionToLanguage;