Fix lookup of an ALIAS target outside aliased target's directory (#16044)

Refactoring in commit v3.5.0-rc1~272^2~11 (cmTarget: Implement ALIAS in
terms of name mapping, 2015-10-25) accidentally introduced logic that
assumes ALIAS targets always reference targets in their own directory.
Fix this and add a test case.

The configure-step fix is that `cmMakefile::FindTarget` should not consider
aliases.  The purpose of this method is just to look up targets local to
a directory.  Since ALIAS and normal targets share a namespace we know a
locally defined target will never collide with an ALIAS target anyway.
The method has 3 call sites, and this change is safe for all of them:

* `cmInstallCommand::HandleTargetsMode`: Rejects aliases before the call.
* `cmFLTKWrapUICommand::FinalPass`: Should never have considered aliases.
* `cmMakefile::FindTargetToUse`: Falls back to a global lookup anyway.

The generate-step fix is that `cmLocalGenerator::FindGeneratorTarget`
should not consider aliases.  This method is the generate-step
equivalent to the above.  The method has 2 call sites, and this change
is safe for both of them:

* `cmInstallTargetGenerator::Compute`: Never uses an alias target name.
* `cmLocalGenerator::FindGeneratorTargetToUse`: Falls back to global lookup.

Reported-by: Matteo Settenvini <matteo@member.fsf.org>

1 files changed, 0 insertions, 11 deletions

diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index 912be0c..6153fbd 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -488,16 +488,6 @@ private:
 cmGeneratorTarget* cmLocalGenerator::FindGeneratorTarget(
     const std::string& name) const
 {
-  std::map<std::string, std::string>::const_iterator i =
-      this->AliasTargets.find(name);
-  if (i != this->AliasTargets.end())
-    {
-    std::vector<cmGeneratorTarget*>::const_iterator ai =
-        std::find_if(this->GeneratorTargets.begin(),
-                     this->GeneratorTargets.end(),
-                     NamedGeneratorTargetFinder(i->second));
-    return *ai;
-    }
   std::vector<cmGeneratorTarget*>::const_iterator ti =
       std::find_if(this->GeneratorTargets.begin(),
                    this->GeneratorTargets.end(),
@@ -506,7 +496,6 @@ cmGeneratorTarget* cmLocalGenerator::FindGeneratorTarget(
     {
     return *ti;
     }
-
   return 0;
 }