CGDebugInfo: At the end of EmitFunctionStart, Initialize PrevLoc to the

location that the next call emitLocation() would default to. Otherwise
setLocation() may wrongly believe that the current source file didn't
change, when in fact it did.

llvm-svn: 204517

2 files changed, 28 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index cfc94430bdf..1a3089a14b2 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -2577,9 +2577,12 @@ void CGDebugInfo::EmitFunctionStart(GlobalDecl GD, QualType FnType,
   if (HasDecl)
     DeclCache.insert(std::make_pair(D->getCanonicalDecl(), llvm::WeakVH(SP)));
 
-  // Push function on region stack.
+  // Push the function onto the lexical block stack.
   llvm::MDNode *SPN = SP;
   LexicalBlockStack.push_back(SPN);
+  // Initialize PrevLoc to the location of the function header.
+  PrevLoc = Loc;
+
   if (HasDecl)
     RegionMap[D] = llvm::WeakVH(SP);
 }
diff --git a/clang/test/CodeGenCXX/linetable-fnbegin.cpp b/clang/test/CodeGenCXX/linetable-fnbegin.cpp
new file mode 100644
index 00000000000..8f8e4c9c789
--- /dev/null
+++ b/clang/test/CodeGenCXX/linetable-fnbegin.cpp
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1 -emit-llvm -g %s -o - | FileCheck %s
+// Test that the line table info for Foo<T>::bar() is pointing to the
+// right header file.
+// CHECK: define{{.*}} @_ZN3FooIiE3barEv
+// CHECK-NOT: define
+// CHECK: ret {{.*}}, !dbg ![[DBG:.*]]
+// CHECK: ![[HPP:.*]] = metadata !{metadata !"./template.hpp",
+// CHECK:![[BLOCK:.*]] = metadata !{{{.*}}, metadata ![[HPP]], {{.*}}} ; [ DW_TAG_lexical_block ]
+// CHECK: [[DBG]] = metadata !{i32 23, i32 0, metadata ![[BLOCK]], null}
+# 1 "./template.h" 1
+template <typename T>
+class Foo {
+public:
+ int bar();
+};
+# 21 "./template.hpp"
+template <typename T>
+int Foo<T>::bar() {
+}
+int main (int argc, const char * argv[])
+{
+  Foo<int> f;
+  f.bar();
+}