Index: llvm/tools/clang/lib/CodeGen/CGDebugInfo.h
===================================================================
--- llvm/tools/clang/lib/CodeGen/CGDebugInfo.h
+++ llvm/tools/clang/lib/CodeGen/CGDebugInfo.h
@@ -283,6 +283,9 @@
   /// \brief - Emit C++ using directive.
   void EmitUsingDirective(const UsingDirectiveDecl &UD);
 
+  /// EmitExplicitCastType - Emit the type explicitly casted to.
+  void EmitExplicitCastType(QualType Ty);
+
   /// \brief - Emit C++ using declaration.
   void EmitUsingDecl(const UsingDecl &UD);
 
Index: llvm/tools/clang/lib/CodeGen/CGDebugInfo.cpp
===================================================================
--- llvm/tools/clang/lib/CodeGen/CGDebugInfo.cpp
+++ llvm/tools/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3347,3 +3347,11 @@
 
   DBuilder.finalize();
 }
+
+void CGDebugInfo::EmitExplicitCastType(QualType Ty) {
+  if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
+    return;
+  llvm::DIType DieTy = getOrCreateType(Ty, getOrCreateMainFile());
+  // Don't ignore in case of explicit cast where it is referenced indirectly.
+  DBuilder.retainType(DieTy);
+}
Index: llvm/tools/clang/lib/CodeGen/CGExprScalar.cpp
===================================================================
--- llvm/tools/clang/lib/CodeGen/CGExprScalar.cpp
+++ llvm/tools/clang/lib/CodeGen/CGExprScalar.cpp
@@ -274,6 +274,10 @@
   Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
     if (E->getType()->isVariablyModifiedType())
       CGF.EmitVariablyModifiedType(E->getType());
+
+    if (CGDebugInfo *DI = CGF.getDebugInfo())
+      DI->EmitExplicitCastType(E->getType());
+
     return VisitCastExpr(E);
   }
   Value *VisitCastExpr(CastExpr *E);
Index: llvm/tools/clang/test/CodeGen/Debug-info-explicitcast.c
===================================================================
--- llvm/tools/clang/test/CodeGen/Debug-info-explicitcast.c
+++ llvm/tools/clang/test/CodeGen/Debug-info-explicitcast.c
@@ -0,0 +1,50 @@
+// RUN: %clang_cc1 -emit-llvm -g %s -o - | FileCheck %s
+
+typedef struct S { int i; } *T;
+
+
+void foo(void *p) { ((T)(p))->i++; }
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"T", i32 3, i64 0, i64 0, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_typedef ] [T] [line 3, size 0, align 0, offset 0] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"S", i32 3, i64 32, i64 32, i32 0, i32 0, null, metadata !{{.*}}, i32 0, null, null, null} ; [ DW_TAG_structure_type ] [S] [line 3, size 32, align 32, offset 0] [def] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"i", i32 3, i64 32, i64 32, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [i] [line 3, size 32, align 32, offset 0] [from int]
+
+typedef struct S1 { int i; } T1;
+void foo1(T1 *p) { p->i++; }
+
+struct S2 {
+  int i;
+};
+void foo2(void *p) { ((struct S2 *)p)->i++; }
+
+struct S3 {
+  int i;
+};
+void foo3(struct S3 *p) { p->i++; }
+
+union U4 {
+  int i;
+  char c;
+};
+void foo4(void *p) { ((union U4 *)p)->i++; }
+
+typedef union U5 {
+  int i;
+  char c;
+} T5;
+
+void foo5(void *p) { ((T5 *)p)->i++; }
+
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"S2", i32 14, i64 32, i64 32, i32 0, i32 0, null, metadata !{{.*}}, i32 0, null, null, null} ; [ DW_TAG_structure_type ] [S2] [line 14, size 32, align 32, offset 0] [def] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"i", i32 15, i64 32, i64 32, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [i] [line 15, size 32, align 32, offset 0] [from int]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"U4", i32 24, i64 32, i64 32, i64 0, i32 0, null, metadata !{{.*}}, i32 0, null, null, null} ; [ DW_TAG_union_type ] [U4] [line 24, size 32, align 32, offset 0] [def] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"i", i32 25, i64 32, i64 32, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [i] [line 25, size 32, align 32, offset 0] [from int]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"c", i32 26, i64 8, i64 8, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [c] [line 26, size 8, align 8, offset 0] [from char]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"T5", i32 33, i64 0, i64 0, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_typedef ] [T5] [line 33, size 0, align 0, offset 0] [from U5]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"U5", i32 30, i64 32, i64 32, i64 0, i32 0, null, metadata !{{.*}}, i32 0, null, null, null} ; [ DW_TAG_union_type ] [U5] [line 30, size 32, align 32, offset 0] [def] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"i", i32 31, i64 32, i64 32, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [i] [line 31, size 32, align 32, offset 0] [from int]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"c", i32 32, i64 8, i64 8, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [c] [line 32, size 8, align 8, offset 0] [from char]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"T1", i32 11, i64 0, i64 0, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_typedef ] [T1] [line 11, size 0, align 0, offset 0] [from S1]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"S1", i32 11, i64 32, i64 32, i32 0, i32 0, null, metadata !{{.*}}, i32 0, null, null, null} ; [ DW_TAG_structure_type ] [S1] [line 11, size 32, align 32, offset 0] [def] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"i", i32 11, i64 32, i64 32, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [i] [line 11, size 32, align 32, offset 0] [from int]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, null, metadata !"S3", i32 19, i64 32, i64 32, i32 0, i32 0, null, metadata !{{.*}}, i32 0, null, null, null} ; [ DW_TAG_structure_type ] [S3] [line 19, size 32, align 32, offset 0] [def] [from ]
+// CHECK: metadata !{i32 {{.*}}, metadata !{{.*}}, metadata !{{.*}}, metadata !"i", i32 20, i64 32, i64 32, i64 0, i32 0, metadata !{{.*}}} ; [ DW_TAG_member ] [i] [line 20, size 32, align 32, offset 0] [from int]