Define 'multiplicity' for cyclic dependencies

We create target property "LINK_INTERFACE_MULTIPLICITY" and a per-config
version "LINK_INTERFACE_MULTIPLICITY_<CONFIG>".  It sets the number of
times a linker should scan through a mutually dependent group of static
libraries.  The largest value of this property on any target in the
group is used.  This will help projects link even for extreme cases of
cyclic inter-target dependencies.

1 files changed, 22 insertions, 1 deletions

diff --git a/Source/cmComputeLinkDepends.cxx b/Source/cmComputeLinkDepends.cxx
index 50a63eb..b5cee42 100644
--- a/Source/cmComputeLinkDepends.cxx
+++ b/Source/cmComputeLinkDepends.cxx
@@ -900,7 +900,7 @@ cmComputeLinkDepends::MakePendingComponent(unsigned int component)
     // advantage that the item directly linked by a target requiring
     // this component will come first which minimizes the number of
     // repeats needed.
-    pc.Count = 2;
+    pc.Count = this->ComputeComponentCount(nl);
     }
 
   // Store the entries to be seen.
@@ -910,6 +910,27 @@ cmComputeLinkDepends::MakePendingComponent(unsigned int component)
 }
 
 //----------------------------------------------------------------------------
+int cmComputeLinkDepends::ComputeComponentCount(NodeList const& nl)
+{
+  int count = 2;
+  for(NodeList::const_iterator ni = nl.begin(); ni != nl.end(); ++ni)
+    {
+    if(cmTarget* target = this->EntryList[*ni].Target)
+      {
+      if(cmTarget::LinkInterface const* iface =
+         target->GetLinkInterface(this->Config))
+        {
+        if(iface->Multiplicity > count)
+          {
+          count = iface->Multiplicity;
+          }
+        }
+      }
+    }
+  return count;
+}
+
+//----------------------------------------------------------------------------
 void cmComputeLinkDepends::DisplayFinalEntries()
 {
   fprintf(stderr, "target [%s] links to:\n", this->Target->GetName());