From 9342a939eb0aac1f08e2799de33880b7061d3590 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Tue, 29 Mar 2005 19:16:59 +0000
Subject: [PATCH] Fix a problem where we not marking incoming arguments to
 functions with external linkage as incomplete.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20927 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Analysis/DataStructure/DataStructure.cpp |  3 ++-
 lib/Analysis/DataStructure/Steensgaard.cpp   | 16 ++++++++++++----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp
index 6460287ac71..7bad52ac3c9 100644
--- a/lib/Analysis/DataStructure/DataStructure.cpp
+++ b/lib/Analysis/DataStructure/DataStructure.cpp
@@ -1657,7 +1657,8 @@ void DSGraph::markIncompleteNodes(unsigned Flags) {
     for (ReturnNodesTy::iterator FI = ReturnNodes.begin(), E =ReturnNodes.end();
          FI != E; ++FI) {
       Function &F = *FI->first;
-      for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I)
+      for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end();
+           I != E; ++I)
         if (isPointerType(I->getType()))
           markIncompleteNode(getNodeForValue(I).getNode());
       markIncompleteNode(FI->second.getNode());
diff --git a/lib/Analysis/DataStructure/Steensgaard.cpp b/lib/Analysis/DataStructure/Steensgaard.cpp
index aa7f54b8904..747ae2fc4b7 100644
--- a/lib/Analysis/DataStructure/Steensgaard.cpp
+++ b/lib/Analysis/DataStructure/Steensgaard.cpp
@@ -167,14 +167,22 @@ bool Steens::runOnModule(Module &M) {
     }
   }
 
-  // Remove our knowledge of what the return values of the functions are.
-  ResultGraph->getReturnNodes().clear();
+  // Remove our knowledge of what the return values of the functions are, except
+  // for functions that are externally visible from this module (e.g. main).  We
+  // keep these functions so that their arguments are marked incomplete.
+  for (DSGraph::ReturnNodesTy::iterator I =
+         ResultGraph->getReturnNodes().begin(),
+         E = ResultGraph->getReturnNodes().end(); I != E; )
+    if (I->first->hasInternalLinkage())
+      ResultGraph->getReturnNodes().erase(I++);
+    else
+      ++I;
 
   // Update the "incomplete" markers on the nodes, ignoring unknownness due to
   // incoming arguments...
   ResultGraph->maskIncompleteMarkers();
-  ResultGraph->markIncompleteNodes(DSGraph::IgnoreFormalArgs |
-                                   DSGraph::IgnoreGlobals);
+  ResultGraph->markIncompleteNodes(DSGraph::IgnoreGlobals |
+                                   DSGraph::MarkFormalArgs);
 
   // Remove any nodes that are dead after all of the merging we have done...
   // FIXME: We should be able to disable the globals graph for steens!