Index: lldb/trunk/source/Plugins/SymbolFile/NativePDB/PdbIndex.cpp
===================================================================
--- lldb/trunk/source/Plugins/SymbolFile/NativePDB/PdbIndex.cpp
+++ lldb/trunk/source/Plugins/SymbolFile/NativePDB/PdbIndex.cpp
@@ -131,10 +131,7 @@
     SegmentOffset so = GetSegmentAndOffset(*iter);
     lldb::addr_t va = MakeVirtualAddress(so);
 
-    // We need to add 4 here to adjust for the codeview debug magic
-    // at the beginning of the debug info stream.
-    uint32_t sym_offset = iter.offset() + 4;
-    PdbCompilandSymId cu_sym_id(modi, sym_offset);
+    PdbCompilandSymId cu_sym_id(modi, iter.offset());
 
     // If the debug info is incorrect, we could have multiple symbols with the
     // same address.  So use try_emplace instead of insert, and the first one
@@ -201,7 +198,7 @@
   // We need to subtract 4 here to adjust for the codeview debug magic
   // at the beginning of the debug info stream.
   const CompilandIndexItem *cci = compilands().GetCompiland(cu_sym.modi);
-  auto iter = cci->m_debug_stream.getSymbolArray().at(cu_sym.offset - 4);
+  auto iter = cci->m_debug_stream.getSymbolArray().at(cu_sym.offset);
   lldbassert(iter != cci->m_debug_stream.getSymbolArray().end());
   return *iter;
 }
Index: llvm/trunk/include/llvm/Support/BinaryStreamArray.h
===================================================================
--- llvm/trunk/include/llvm/Support/BinaryStreamArray.h
+++ llvm/trunk/include/llvm/Support/BinaryStreamArray.h
@@ -96,17 +96,19 @@
 
   explicit VarStreamArray(const Extractor &E) : E(E) {}
 
-  explicit VarStreamArray(BinaryStreamRef Stream) : Stream(Stream) {}
+  explicit VarStreamArray(BinaryStreamRef Stream, uint32_t Skew = 0)
+      : Stream(Stream), Skew(Skew) {}
 
-  VarStreamArray(BinaryStreamRef Stream, const Extractor &E)
-      : Stream(Stream), E(E) {}
+  VarStreamArray(BinaryStreamRef Stream, const Extractor &E, uint32_t Skew = 0)
+      : Stream(Stream), E(E), Skew(Skew) {}
 
   Iterator begin(bool *HadError = nullptr) const {
-    return Iterator(*this, E, HadError);
+    return Iterator(*this, E, Skew, nullptr);
   }
 
   bool valid() const { return Stream.valid(); }
 
+  uint32_t skew() const { return Skew; }
   Iterator end() const { return Iterator(E); }
 
   bool empty() const { return Stream.getLength() == 0; }
@@ -123,13 +125,17 @@
   Extractor &getExtractor() { return E; }
 
   BinaryStreamRef getUnderlyingStream() const { return Stream; }
-  void setUnderlyingStream(BinaryStreamRef S) { Stream = S; }
+  void setUnderlyingStream(BinaryStreamRef S, uint32_t Skew = 0) {
+    Stream = S;
+    this->Skew = Skew;
+  }
 
   void drop_front() { Stream = Stream.drop_front(begin()->length()); }
 
 private:
   BinaryStreamRef Stream;
   Extractor E;
+  uint32_t Skew;
 };
 
 template <typename ValueType, typename Extractor>
@@ -141,10 +147,6 @@
 
 public:
   VarStreamArrayIterator(const ArrayType &Array, const Extractor &E,
-                         bool *HadError)
-      : VarStreamArrayIterator(Array, E, 0, HadError) {}
-
-  VarStreamArrayIterator(const ArrayType &Array, const Extractor &E,
                          uint32_t Offset, bool *HadError)
       : IterRef(Array.Stream.drop_front(Offset)), Extract(E),
         Array(&Array), AbsOffset(Offset), HadError(HadError) {
Index: llvm/trunk/include/llvm/Support/BinaryStreamReader.h
===================================================================
--- llvm/trunk/include/llvm/Support/BinaryStreamReader.h
+++ llvm/trunk/include/llvm/Support/BinaryStreamReader.h
@@ -203,11 +203,12 @@
   /// \returns a success error code if the data was successfully read, otherwise
   /// returns an appropriate error code.
   template <typename T, typename U>
-  Error readArray(VarStreamArray<T, U> &Array, uint32_t Size) {
+  Error readArray(VarStreamArray<T, U> &Array, uint32_t Size,
+                  uint32_t Skew = 0) {
     BinaryStreamRef S;
     if (auto EC = readStreamRef(S, Size))
       return EC;
-    Array.setUnderlyingStream(S);
+    Array.setUnderlyingStream(S, Skew);
     return Error::success();
   }
 
Index: llvm/trunk/lib/DebugInfo/CodeView/CVSymbolVisitor.cpp
===================================================================
--- llvm/trunk/lib/DebugInfo/CodeView/CVSymbolVisitor.cpp
+++ llvm/trunk/lib/DebugInfo/CodeView/CVSymbolVisitor.cpp
@@ -75,7 +75,7 @@
 Error CVSymbolVisitor::visitSymbolStream(const CVSymbolArray &Symbols,
                                          uint32_t InitialOffset) {
   for (auto I : Symbols) {
-    if (auto EC = visitSymbolRecord(I, InitialOffset))
+    if (auto EC = visitSymbolRecord(I, InitialOffset + Symbols.skew()))
       return EC;
     InitialOffset += I.length();
   }
Index: llvm/trunk/lib/DebugInfo/PDB/Native/ModuleDebugStream.cpp
===================================================================
--- llvm/trunk/lib/DebugInfo/PDB/Native/ModuleDebugStream.cpp
+++ llvm/trunk/lib/DebugInfo/PDB/Native/ModuleDebugStream.cpp
@@ -47,7 +47,8 @@
 
   if (auto EC = Reader.readInteger(Signature))
     return EC;
-  if (auto EC = Reader.readSubstream(SymbolsSubstream, SymbolSize - 4))
+  Reader.setOffset(0);
+  if (auto EC = Reader.readSubstream(SymbolsSubstream, SymbolSize))
     return EC;
   if (auto EC = Reader.readSubstream(C11LinesSubstream, C11Size))
     return EC;
@@ -55,8 +56,8 @@
     return EC;
 
   BinaryStreamReader SymbolReader(SymbolsSubstream.StreamData);
-  if (auto EC =
-          SymbolReader.readArray(SymbolArray, SymbolReader.bytesRemaining()))
+  if (auto EC = SymbolReader.readArray(
+          SymbolArray, SymbolReader.bytesRemaining(), sizeof(uint32_t)))
     return EC;
 
   BinaryStreamReader SubsectionsReader(C13LinesSubstream.StreamData);
@@ -98,9 +99,7 @@
 }
 
 CVSymbol ModuleDebugStreamRef::readSymbolAtOffset(uint32_t Offset) const {
-  // Offsets include the size of the 4-byte magic at the beginning, but lookup
-  // doesn't take that into account, so subtract it here.
-  auto Iter = SymbolArray.at(Offset - 4);
+  auto Iter = SymbolArray.at(Offset);
   assert(Iter != SymbolArray.end());
   return *Iter;
 }
Index: llvm/trunk/test/DebugInfo/PDB/module-bytes.test
===================================================================
--- llvm/trunk/test/DebugInfo/PDB/module-bytes.test
+++ llvm/trunk/test/DebugInfo/PDB/module-bytes.test
@@ -42,44 +42,45 @@
 SYMS-NEXT: ============================================================
 SYMS-NEXT:     Mod 0000 | `d:\src\llvm\test\DebugInfo\PDB\Inputs\empty.obj`:
 SYMS-NEXT:       Symbols (
-SYMS-NEXT:         6004: 36000111 00000000 643A5C73 72635C6C 6C766D5C 74657374 5C446562 7567496E  |6.......d:\src\llvm\test\DebugIn|
-SYMS-NEXT:         6024: 666F5C50 44425C49 6E707574 735C656D 7074792E 6F626A00 3A003C11 01200000  |fo\PDB\Inputs\empty.obj.:.<.. ..|
-SYMS-NEXT:         6044: 07001200 00007D79 00001200 00007D79 00004D69 63726F73 6F667420 28522920  |......}y......}y..Microsoft (R) |
-SYMS-NEXT:         6064: 4F707469 6D697A69 6E672043 6F6D7069 6C657200 2A001011 00000000 C4000000  |Optimizing Compiler.*...........|
-SYMS-NEXT:         6084: 00000000 0A000000 03000000 08000000 01100000 10000000 0100016D 61696E00  |...........................main.|
-SYMS-NEXT:         60A4: 1E001210 00000000 00000000 00000000 00000000 00000000 00000082 12000000  |................................|
-SYMS-NEXT:         60C4: 02000600 06004C11 0E100000                                               |......L.....|
+SYMS-NEXT:         6000: 04000000 36000111 00000000 643A5C73 72635C6C 6C766D5C 74657374 5C446562  |....6.......d:\src\llvm\test\Deb|
+SYMS-NEXT:         6020: 7567496E 666F5C50 44425C49 6E707574 735C656D 7074792E 6F626A00 3A003C11  |ugInfo\PDB\Inputs\empty.obj.:.<.|
+SYMS-NEXT:         6040: 01200000 07001200 00007D79 00001200 00007D79 00004D69 63726F73 6F667420  |. ........}y......}y..Microsoft |
+SYMS-NEXT:         6060: 28522920 4F707469 6D697A69 6E672043 6F6D7069 6C657200 2A001011 00000000  |(R) Optimizing Compiler.*.......|
+SYMS-NEXT:         6080: C4000000 00000000 0A000000 03000000 08000000 01100000 10000000 0100016D  |...............................m|
+SYMS-NEXT:         60A0: 61696E00 1E001210 00000000 00000000 00000000 00000000 00000000 00000082  |ain.............................|
+SYMS-NEXT:         60C0: 12000000 02000600 06004C11 0E100000                                      |..........L.....|
 SYMS-NEXT:       )
 SYMS-NEXT:     Mod 0001 | `* Linker *`:
 SYMS-NEXT:       Symbols (
-SYMS-NEXT:         7004: 12000111 00000000 2A204C69 6E6B6572 202A0000 2E003C11 07000000 03000000  |........* Linker *....<.........|
-SYMS-NEXT:         7024: 00000000 00000C00 00007D79 00004D69 63726F73 6F667420 28522920 4C494E4B  |..........}y..Microsoft (R) LINK|
-SYMS-NEXT:         7044: 00000000 AA003D11 00637764 00643A5C 7372635C 6C6C766D 5C746573 745C4465  |......=..cwd.d:\src\llvm\test\De|
-SYMS-NEXT:         7064: 62756749 6E666F5C 5044425C 496E7075 74730065 78650043 3A5C5072 6F677261  |bugInfo\PDB\Inputs.exe.C:\Progra|
-SYMS-NEXT:         7084: 6D204669 6C657320 28783836 295C4D69 63726F73 6F667420 56697375 616C2053  |m Files (x86)\Microsoft Visual S|
-SYMS-NEXT:         70A4: 74756469 6F203132 2E305C56 435C4249 4E5C6C69 6E6B2E65 78650070 64620064  |tudio 12.0\VC\BIN\link.exe.pdb.d|
-SYMS-NEXT:         70C4: 3A5C7372 635C6C6C 766D5C74 6573745C 44656275 67496E66 6F5C5044 425C496E  |:\src\llvm\test\DebugInfo\PDB\In|
-SYMS-NEXT:         70E4: 70757473 5C656D70 74792E70 64620000 12002C11 00000500 05000000 10000000  |puts\empty.pdb....,.............|
-SYMS-NEXT:         7104: 01000100 1A003611 01000C00 00100000 1A100000 20000060 2E746578 74000000  |......6............. ..`.text...|
-SYMS-NEXT:         7124: 1A003711 1A100000 20000060 00000000 01002E74 65787424 6D6E0000 1A003611  |..7..... ..`.......text$mn....6.|
-SYMS-NEXT:         7144: 02000C00 00300000 B2020000 40000040 2E726461 74610000 1A003711 43010000  |.....0......@..@.rdata....7.C...|
-SYMS-NEXT:         7164: 40000040 00000000 02002E72 64617461 00000000 1A003711 00000000 40000040  |@..@.......rdata......7.....@..@|
-SYMS-NEXT:         7184: 43010000 02002E65 64617461 00000000 1E003711 6E010000 40000040 44010000  |C......edata......7.n...@..@D...|
-SYMS-NEXT:         71A4: 02002E72 64617461 24646562 75670000 1A003611 03000C00 00400000 04000000  |...rdata$debug....6......@......|
-SYMS-NEXT:         71C4: 400000C0 2E646174 61000000 16003711 04000000 800000C0 00000000 03002E62  |@....data.....7................b|
-SYMS-NEXT:         71E4: 73730000 1A003611 04000C00 00500000 08000000 40000042 2E72656C 6F630000  |ss....6......P......@..B.reloc..|
+SYMS-NEXT:         7000: 04000000 12000111 00000000 2A204C69 6E6B6572 202A0000 2E003C11 07000000  |............* Linker *....<.....|
+SYMS-NEXT:         7020: 03000000 00000000 00000C00 00007D79 00004D69 63726F73 6F667420 28522920  |..............}y..Microsoft (R) |
+SYMS-NEXT:         7040: 4C494E4B 00000000 AA003D11 00637764 00643A5C 7372635C 6C6C766D 5C746573  |LINK......=..cwd.d:\src\llvm\tes|
+SYMS-NEXT:         7060: 745C4465 62756749 6E666F5C 5044425C 496E7075 74730065 78650043 3A5C5072  |t\DebugInfo\PDB\Inputs.exe.C:\Pr|
+SYMS-NEXT:         7080: 6F677261 6D204669 6C657320 28783836 295C4D69 63726F73 6F667420 56697375  |ogram Files (x86)\Microsoft Visu|
+SYMS-NEXT:         70A0: 616C2053 74756469 6F203132 2E305C56 435C4249 4E5C6C69 6E6B2E65 78650070  |al Studio 12.0\VC\BIN\link.exe.p|
+SYMS-NEXT:         70C0: 64620064 3A5C7372 635C6C6C 766D5C74 6573745C 44656275 67496E66 6F5C5044  |db.d:\src\llvm\test\DebugInfo\PD|
+SYMS-NEXT:         70E0: 425C496E 70757473 5C656D70 74792E70 64620000 12002C11 00000500 05000000  |B\Inputs\empty.pdb....,.........|
+SYMS-NEXT:         7100: 10000000 01000100 1A003611 01000C00 00100000 1A100000 20000060 2E746578  |..........6............. ..`.tex|
+SYMS-NEXT:         7120: 74000000 1A003711 1A100000 20000060 00000000 01002E74 65787424 6D6E0000  |t.....7..... ..`.......text$mn..|
+SYMS-NEXT:         7140: 1A003611 02000C00 00300000 B2020000 40000040 2E726461 74610000 1A003711  |..6......0......@..@.rdata....7.|
+SYMS-NEXT:         7160: 43010000 40000040 00000000 02002E72 64617461 00000000 1A003711 00000000  |C...@..@.......rdata......7.....|
+SYMS-NEXT:         7180: 40000040 43010000 02002E65 64617461 00000000 1E003711 6E010000 40000040  |@..@C......edata......7.n...@..@|
+SYMS-NEXT:         71A0: 44010000 02002E72 64617461 24646562 75670000 1A003611 03000C00 00400000  |D......rdata$debug....6......@..|
+SYMS-NEXT:         71C0: 04000000 400000C0 2E646174 61000000 16003711 04000000 800000C0 00000000  |....@....data.....7.............|
+SYMS-NEXT:         71E0: 03002E62 73730000 1A003611 04000C00 00500000 08000000 40000042 2E72656C  |...bss....6......P......@..B.rel|
+SYMS-NEXT:         7200: 6F630000                                                                 |oc..|
 SYMS-NEXT:       )
 
 FILTERED-SYMS:                             Module Symbols
 FILTERED-SYMS-NEXT: ============================================================
 FILTERED-SYMS-NEXT:     Mod 0000 | `d:\src\llvm\test\DebugInfo\PDB\Inputs\empty.obj`:
 FILTERED-SYMS-NEXT:       Symbols (
-FILTERED-SYMS-NEXT:         6004: 36000111 00000000 643A5C73 72635C6C 6C766D5C 74657374 5C446562 7567496E  |6.......d:\src\llvm\test\DebugIn|
-FILTERED-SYMS-NEXT:         6024: 666F5C50 44425C49 6E707574 735C656D 7074792E 6F626A00 3A003C11 01200000  |fo\PDB\Inputs\empty.obj.:.<.. ..|
-FILTERED-SYMS-NEXT:         6044: 07001200 00007D79 00001200 00007D79 00004D69 63726F73 6F667420 28522920  |......}y......}y..Microsoft (R) |
-FILTERED-SYMS-NEXT:         6064: 4F707469 6D697A69 6E672043 6F6D7069 6C657200 2A001011 00000000 C4000000  |Optimizing Compiler.*...........|
-FILTERED-SYMS-NEXT:         6084: 00000000 0A000000 03000000 08000000 01100000 10000000 0100016D 61696E00  |...........................main.|
-FILTERED-SYMS-NEXT:         60A4: 1E001210 00000000 00000000 00000000 00000000 00000000 00000082 12000000  |................................|
-FILTERED-SYMS-NEXT:         60C4: 02000600 06004C11 0E100000                                               |......L.....|
+FILTERED-SYMS-NEXT:         6000: 04000000 36000111 00000000 643A5C73 72635C6C 6C766D5C 74657374 5C446562  |....6.......d:\src\llvm\test\Deb|
+FILTERED-SYMS-NEXT:         6020: 7567496E 666F5C50 44425C49 6E707574 735C656D 7074792E 6F626A00 3A003C11  |ugInfo\PDB\Inputs\empty.obj.:.<.|
+FILTERED-SYMS-NEXT:         6040: 01200000 07001200 00007D79 00001200 00007D79 00004D69 63726F73 6F667420  |. ........}y......}y..Microsoft |
+FILTERED-SYMS-NEXT:         6060: 28522920 4F707469 6D697A69 6E672043 6F6D7069 6C657200 2A001011 00000000  |(R) Optimizing Compiler.*.......|
+FILTERED-SYMS-NEXT:         6080: C4000000 00000000 0A000000 03000000 08000000 01100000 10000000 0100016D  |...............................m|
+FILTERED-SYMS-NEXT:         60A0: 61696E00 1E001210 00000000 00000000 00000000 00000000 00000000 00000082  |ain.............................|
+FILTERED-SYMS-NEXT:         60C0: 12000000 02000600 06004C11 0E100000                                      |..........L.....|
 FILTERED-SYMS-NEXT:       )
 FILTERED-SYMS-NOT:      Mod 0001