fix crashes when we only have a prototype for main.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20627 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/DataStructure/BottomUpClosure.cpp b/lib/Analysis/DataStructure/BottomUpClosure.cpp
index 6c26602..91cfc7c 100644
--- a/lib/Analysis/DataStructure/BottomUpClosure.cpp
+++ b/lib/Analysis/DataStructure/BottomUpClosure.cpp
@@ -85,7 +85,7 @@
// Merge the globals variables (not the calls) from the globals graph back
// into the main function's graph so that the main function contains all of
// the information about global pools and GV usage in the program.
- if (MainFunc) {
+ if (MainFunc && !MainFunc->isExternal()) {
DSGraph &MainGraph = getOrCreateGraph(MainFunc);
const DSGraph &GG = *MainGraph.getGlobalsGraph();
ReachabilityCloner RC(MainGraph, GG,