3 files changed, 35 insertions, 8 deletions
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index f2ca2e7c589..a652ede1c1f 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -34,7 +34,7 @@ using namespace clang;
 using namespace clang::CodeGen;
 
 CGDebugInfo::CGDebugInfo(CodeGenModule *m)
-  : M(m), DebugFactory(M->getModule()) {
+  : M(m), isMainCompileUnitCreated(false), DebugFactory(M->getModule()) {
 }
 
 CGDebugInfo::~CGDebugInfo() {
@@ -71,16 +71,22 @@ llvm::DICompileUnit CGDebugInfo::getOrCreateCompileUnit(SourceLocation Loc) {
     AbsFileName = tmp;
   }
 
-  // See if thie compile unit is represnting main source file.
+  // See if thie compile unit is representing main source file. Each source
+  // file has corresponding compile unit. There is only one main source
+  // file at a time.
   bool isMain = false;
   const LangOptions &LO = M->getLangOptions();
   const char *MainFileName = LO.getMainFileName();
-  if (MainFileName) {
-    if (!strcmp(AbsFileName.getLast().c_str(), MainFileName))
-      isMain = true;
-  } else {
-    if (Loc.isValid() && SM.isFromMainFile(Loc))
-      isMain = true;
+  if (isMainCompileUnitCreated == false) {
+    if (MainFileName) {
+      if (!strcmp(AbsFileName.getLast().c_str(), MainFileName))
+        isMain = true;
+    } else {
+      if (Loc.isValid() && SM.isFromMainFile(Loc))
+        isMain = true;
+    }
+    if (isMain)
+      isMainCompileUnitCreated = true;
   }
 
   unsigned LangTag;
diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h
index 4a59ecaaa57..1581637f4a3 100644
--- a/clang/lib/CodeGen/CGDebugInfo.h
+++ b/clang/lib/CodeGen/CGDebugInfo.h
@@ -34,6 +34,7 @@ namespace CodeGen {
 /// the backend.
 class CGDebugInfo {
   CodeGenModule *M;
+  bool isMainCompileUnitCreated;
   llvm::DIFactory DebugFactory;
   
   SourceLocation CurLoc, PrevLoc;
diff --git a/clang/test/CodeGen/2009-04-23-dbg.c b/clang/test/CodeGen/2009-04-23-dbg.c
new file mode 100644
index 00000000000..4be6dab7ea2
--- /dev/null
+++ b/clang/test/CodeGen/2009-04-23-dbg.c
@@ -0,0 +1,20 @@
+// RUN: clang-cc -g -o %t  %s -emit-llvm-bc && llc %t -f -o %t.s
+# 1 "a.c"
+# 1 "a.c" 1
+# 1 "<built-in>" 1
+# 103 "<built-in>"
+# 103 "<command line>" 1
+
+# 1 "/private/tmp/a.h" 1
+int bar;
+# 105 "<command line>" 2
+# 105 "<built-in>" 2
+# 1 "a.c" 2
+# 1 "/private/tmp/a.h" 1
+int bar;
+# 2 "a.c" 2
+
+int main() {
+ bar = 0;
+ return 0;
+}