cmTarget: Make GetLink*Libraries methods safer to use

Split the library lists out of LinkImplementation and LinkInterface into
LinkImplementationLibraries and LinkInterfaceLibraries parent classes,
respectively.  Return these from GetLinkImplementationLibraries and
GetLinkInterfaceLibraries, respectively, so that callers cannot access
parts of the structures that have not been populated.

1 files changed, 16 insertions, 15 deletions

diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index cdece87..b36a600 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -4379,7 +4379,7 @@ bool cmTarget::HaveBuildTreeRPATH(const std::string& config) const
     {
     return false;
     }
-  if(LinkImplementation const* impl =
+  if(LinkImplementationLibraries const* impl =
      this->GetLinkImplementationLibraries(config))
     {
     return !impl->Libraries.empty();
@@ -5935,7 +5935,7 @@ cmTarget::LinkInterface const* cmTarget::GetLinkInterface(
 }
 
 //----------------------------------------------------------------------------
-cmTarget::LinkInterface const*
+cmTarget::LinkInterfaceLibraries const*
 cmTarget::GetLinkInterfaceLibraries(const std::string& config,
                                     cmTarget const* head,
                                     bool usage_requirements_only) const
@@ -6017,7 +6017,7 @@ void processILibs(const std::string& config,
   if (item.Target && emitted.insert(item.Target).second)
     {
     tgts.push_back(item.Target);
-    if(cmTarget::LinkInterface const* iface =
+    if(cmTarget::LinkInterfaceLibraries const* iface =
        item.Target->GetLinkInterfaceLibraries(config, headTarget, true))
       {
       for(std::vector<cmLinkItem>::const_iterator
@@ -6041,7 +6041,7 @@ cmTarget::GetLinkImplementationClosure(const std::string& config) const
     this->Internal->CacheLinkImplementationClosureDone[config] = true;
     std::set<cmTarget const*> emitted;
 
-    cmTarget::LinkImplementation const* impl
+    cmTarget::LinkImplementationLibraries const* impl
       = this->GetLinkImplementationLibraries(config);
 
     for(std::vector<cmLinkImplItem>::const_iterator
@@ -6059,7 +6059,7 @@ void cmTarget::GetTransitivePropertyTargets(const std::string& config,
                                       cmTarget const* headTarget,
                                       std::vector<cmTarget const*> &tgts) const
 {
-  if(cmTarget::LinkInterface const* iface =
+  if(cmTarget::LinkInterfaceLibraries const* iface =
      this->GetLinkInterfaceLibraries(config, headTarget, true))
     {
     for(std::vector<cmLinkItem>::const_iterator it = iface->Libraries.begin();
@@ -6177,7 +6177,7 @@ cmTargetInternals::ComputeLinkInterfaceLibraries(
     // to the link implementation.
     {
     // The link implementation is the default link interface.
-    cmTarget::LinkImplementation const* impl =
+    cmTarget::LinkImplementationLibraries const* impl =
       thisTarget->GetLinkImplementationLibrariesInternal(config, headTarget);
     std::copy(impl->Libraries.begin(), impl->Libraries.end(),
               std::back_inserter(iface.Libraries));
@@ -6294,7 +6294,7 @@ void cmTargetInternals::ComputeLinkInterface(cmTarget const* thisTarget,
         || thisTarget->PolicyStatusCMP0022 == cmPolicies::OLD)
     {
     // The link implementation is the default link interface.
-    cmTarget::LinkImplementation const*
+    cmTarget::LinkImplementationLibraries const*
       impl = thisTarget->GetLinkImplementationLibrariesInternal(config,
                                                                 headTarget);
     iface.ImplementationIsInterface = true;
@@ -6345,7 +6345,7 @@ void cmTargetInternals::AddInterfaceEntries(
   cmTarget const* thisTarget, std::string const& config,
   std::string const& prop, std::vector<TargetPropertyEntry*>& entries)
 {
-  if(cmTarget::LinkImplementation const* impl =
+  if(cmTarget::LinkImplementationLibraries const* impl =
      thisTarget->GetLinkImplementationLibraries(config))
     {
     for (std::vector<cmLinkImplItem>::const_iterator
@@ -6383,7 +6383,7 @@ cmTarget::GetLinkImplementation(const std::string& config) const
   if(!impl.LibrariesDone)
     {
     impl.LibrariesDone = true;
-    this->ComputeLinkImplementation(config, impl, this);
+    this->ComputeLinkImplementationLibraries(config, impl, this);
     }
   if(!impl.LanguagesDone)
     {
@@ -6394,14 +6394,14 @@ cmTarget::GetLinkImplementation(const std::string& config) const
 }
 
 //----------------------------------------------------------------------------
-cmTarget::LinkImplementation const*
+cmTarget::LinkImplementationLibraries const*
 cmTarget::GetLinkImplementationLibraries(const std::string& config) const
 {
   return this->GetLinkImplementationLibrariesInternal(config, this);
 }
 
 //----------------------------------------------------------------------------
-cmTarget::LinkImplementation const*
+cmTarget::LinkImplementationLibraries const*
 cmTarget::GetLinkImplementationLibrariesInternal(const std::string& config,
                                                  cmTarget const* head) const
 {
@@ -6418,15 +6418,16 @@ cmTarget::GetLinkImplementationLibrariesInternal(const std::string& config,
   if(!impl.LibrariesDone)
     {
     impl.LibrariesDone = true;
-    this->ComputeLinkImplementation(config, impl, head);
+    this->ComputeLinkImplementationLibraries(config, impl, head);
     }
   return &impl;
 }
 
 //----------------------------------------------------------------------------
-void cmTarget::ComputeLinkImplementation(const std::string& config,
-                                         LinkImplementation& impl,
-                                         cmTarget const* head) const
+void
+cmTarget::ComputeLinkImplementationLibraries(const std::string& config,
+                                             LinkImplementation& impl,
+                                             cmTarget const* head) const
 {
   // Collect libraries directly linked in this configuration.
   for (std::vector<cmValueWithOrigin>::const_iterator