Invalidate target link info when necessary

In cmTarget we compute the link implementation, link interface, and link
closure structures on-demand and cache the results.  This commit teaches
cmTarget to invalidate results after a LINK_INTERFACE_* property changes
or a new link library is added.  We also clear the results at the end of
the Configure step to ensure the Generate step uses up-to-date results.

1 files changed, 19 insertions, 0 deletions

diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index d095879..a4f3f2f 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -1030,11 +1030,25 @@ void cmTarget::SetMakefile(cmMakefile* mf)
 //----------------------------------------------------------------------------
 void cmTarget::FinishConfigure()
 {
+  // Erase any cached link information that might have been comptued
+  // on-demand during the configuration.  This ensures that build
+  // system generation uses up-to-date information even if other cache
+  // invalidation code in this source file is buggy.
+  this->ClearLinkMaps();
+
   // Do old-style link dependency analysis.
   this->AnalyzeLibDependencies(*this->Makefile);
 }
 
 //----------------------------------------------------------------------------
+void cmTarget::ClearLinkMaps()
+{
+  this->Internal->LinkImplMap.clear();
+  this->Internal->LinkInterfaceMap.clear();
+  this->Internal->LinkClosureMap.clear();
+}
+
+//----------------------------------------------------------------------------
 cmListFileBacktrace const& cmTarget::GetBacktrace() const
 {
   return this->Internal->Backtrace;
@@ -1656,6 +1670,7 @@ void cmTarget::AddLinkLibrary(cmMakefile& mf,
   tmp.second = llt;
   this->LinkLibraries.push_back( tmp );
   this->OriginalLinkLibraries.push_back(tmp);
+  this->ClearLinkMaps();
 
   // Add the explicit dependency information for this target. This is
   // simply a set of libraries separated by ";". There should always
@@ -2023,6 +2038,10 @@ void cmTarget::MaybeInvalidatePropertyCache(const char* prop)
     {
     this->Internal->ImportInfoMap.clear();
     }
+  if(!this->IsImported() && strncmp(prop, "LINK_INTERFACE_", 15) == 0)
+    {
+    this->ClearLinkMaps();
+    }
 }
 
 //----------------------------------------------------------------------------