[LLDB][NativePDB] Fix a crash when S_DEFRANGE_SUBFIELD_REGISTER descirbes a simple type

[zequanwu]

Summary

When a variable is simple type and has 64 bits, the debug info may look like the following when targeting 32bit windows. The variable's content is split into two 32bits registers.

480 | S_LOCAL [size = 12] `x`
      type=0x0013 (__int64), flags = param
492 | S_DEFRANGE_SUBFIELD_REGISTER [size = 20]
      register = EAX, may have no name = true, offset in parent = 0
      range = [0001:0073,+7), gaps = []
512 | S_DEFRANGE_SUBFIELD_REGISTER [size = 20]
      register = ECX, may have no name = true, offset in parent = 4
      range = [0001:0073,+7), gaps = []

[labath]

Seems reasonable, but I don't know much about pdb's. @rnk, do you want to take a look?

lldb/source/Plugins/SymbolFile/NativePDB/PdbUtil.cpp

53–54

I think SmallVectorImpl is still the official way to take SmallVector references.

[aganea]

There's a typo in the title, s/descirbes/describes/

lldb/source/Plugins/SymbolFile/NativePDB/PdbUtil.cpp

53–54

ArrayRef would be even better! :) ie. llvm::ArrayRef<std::pair<RegisterId, uint32_t>> members_info;

lldb/test/Shell/SymbolFile/NativePDB/subfield_register_simple_type.s

28

nitpick: Is anything after (and including) ", valid ranges" necessary to cover this change?

[zequanwu]

Update.

lldb/source/Plugins/SymbolFile/NativePDB/PdbUtil.cpp

53–54

Using SmallVectorImpl because we want to insert elements in visitKnownMember.

lldb/test/Shell/SymbolFile/NativePDB/subfield_register_simple_type.s

28

Yes, the structure of location is basically what we are testing against though the register number maybe incorrect due to the FIXME above.

[zequanwu]

Ping.

[augusto2112]

Hi @zequanwu, your patch's new test seems to be failing on CI (https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/). Could you fix it or revert the changes? Thanks!

[zequanwu]

In D122943#3453663, @augusto2112 wrote:

Hi @zequanwu, your patch's new test seems to be failing on CI (https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/). Could you fix it or revert the changes? Thanks!

Thanks, https://github.com/llvm/llvm-project/commit/2f78f9455f85e61fcfeb1dc3a13d62c912aa0c96 should fix it.

lldb/source/Plugins/SymbolFile/NativePDB/PdbUtil.cpp

while (!gaps.empty()) {
     gaps = gaps.drop_front();
   }
 
   result.Append(start, end - start);
   return result;
 }
 
 namespace {
 struct FindMembersSize : public TypeVisitorCallbacks {
-  FindMembersSize(std::vector<std::pair<RegisterId, uint32_t>> &members_info,
-                  TpiStream &tpi)
+  FindMembersSize(
+      llvm::SmallVectorImpl<std::pair<RegisterId, uint32_t>> &members_info,
       : members_info(members_info), tpi(tpi) {}
-  std::vector<std::pair<RegisterId, uint32_t>> &members_info;
+  llvm::SmallVectorImpl<std::pair<RegisterId, uint32_t>> &members_info;
   TpiStream &tpi;
   llvm::Error visitKnownMember(CVMemberRecord &cvr,
                                DataMemberRecord &member) override {
     members_info.emplace_back(llvm::codeview::RegisterId::NONE,
                               GetSizeOfType(member.Type, tpi));
     return llvm::Error::success();
   }
 };
case S_DEFRANGE_FRAMEPOINTER_REL: {
           // invalid variable
         }
       } else {
         result.location =
             MakeRegRelLocationExpression(base_reg, loc.Hdr.Offset, module);
         result.ranges = std::move(ranges);
       }
       break;
-    } 
+    }
     case S_DEFRANGE_REGISTER_REL: {
       DefRangeRegisterRelSym loc(SymbolRecordKind::DefRangeRegisterRelSym);
       cantFail(SymbolDeserializer::deserializeAs<DefRangeRegisterRelSym>(
           loc_specifier_cvs, loc));
 
       Variable::RangeList ranges = MakeRangeList(index, loc.Range, loc.Gaps);
 
       RegisterId base_reg = (RegisterId)(uint16_t)loc.Hdr.Register;
case S_DEFRANGE_REGISTER: {
           loc_specifier_cvs, loc));
 
       RegisterId base_reg = (RegisterId)(uint16_t)loc.Hdr.Register;
       result.ranges = MakeRangeList(index, loc.Range, loc.Gaps);
       result.location = MakeEnregisteredLocationExpression(base_reg, module);
       break;
     }
     case S_DEFRANGE_SUBFIELD_REGISTER: {
+      // A vector of register id and member size pairs. If the variable is a
+      // simple type, then we don't know the number of subfields. Otherwise, the
+      // vector size will be the number of subfields in the udt type.
+      llvm::SmallVector<std::pair<RegisterId, uint32_t>> members_info;
+      bool is_simple_type = result.type.isSimple();
+      if (!is_simple_type) {
         CVType class_cvt = index.tpi().getType(result.type);
         ClassRecord class_record = CVTagRecord::create(class_cvt).asClass();
         CVType field_list = index.tpi().getType(class_record.FieldList);
-      std::vector<std::pair<RegisterId, uint32_t>> members_info;
         FindMembersSize find_members_size(members_info, index.tpi());
         if (llvm::Error err =
-              visitMemberRecordStream(field_list.data(), find_members_size))
+                visitMemberRecordStream(field_list.data(), find_members_size)) {
           llvm::consumeError(std::move(err));
+          break;
+        }
+      }
 
-      std::vector<Variable::RangeList> range_lists;
+      uint32_t prev_offset = 0;
       uint32_t cur_offset = 0;
       size_t member_idx = 0;
       // Assuming S_DEFRANGE_SUBFIELD_REGISTER is followed only by
       // S_DEFRANGE_SUBFIELD_REGISTER, need to verify.
-      while (loc_specifier_cvs.kind() == S_DEFRANGE_SUBFIELD_REGISTER &&
-             member_idx < members_info.size()) {
+      while (loc_specifier_cvs.kind() == S_DEFRANGE_SUBFIELD_REGISTER) {
+        if (!is_simple_type && member_idx >= members_info.size())
+          break;
+
         DefRangeSubfieldRegisterSym loc(
             SymbolRecordKind::DefRangeSubfieldRegisterSym);
         cantFail(SymbolDeserializer::deserializeAs<DefRangeSubfieldRegisterSym>(
             loc_specifier_cvs, loc));
 
         if (result.ranges) {
           result.ranges = Variable::RangeList::GetOverlaps(
               *result.ranges, MakeRangeList(index, loc.Range, loc.Gaps));
         } else {
           result.ranges = MakeRangeList(index, loc.Range, loc.Gaps);
           result.ranges->Sort();
         }
 
+        if (is_simple_type) {
+          // Fix last member's size.
+          if (!members_info.empty())
+            members_info.back().second =
+                loc.Hdr.OffsetInParent - prev_offset;
+          members_info.emplace_back((RegisterId)(uint16_t)loc.Hdr.Register, 0);
+          prev_offset = loc.Hdr.OffsetInParent;
+        } else {
           // Some fields maybe optimized away and have no
           // S_DEFRANGE_SUBFIELD_REGISTER to describe them. Skip them.
-        while (loc.Hdr.OffsetInParent != cur_offset) {
+          while (loc.Hdr.OffsetInParent != cur_offset &&
+                 member_idx < members_info.size()) {
             cur_offset += members_info[member_idx].second;
             ++member_idx;
           }
           if (member_idx < members_info.size()) {
             members_info[member_idx].first =
                 (RegisterId)(uint16_t)loc.Hdr.Register;
             cur_offset += members_info[member_idx].second;
             ++member_idx;
           }
+        }
         // Go to next S_DEFRANGE_SUBFIELD_REGISTER.
         loc_specifier_id = PdbCompilandSymId(
             loc_specifier_id.modi,
             loc_specifier_id.offset + loc_specifier_cvs.RecordData.size());
         loc_specifier_cvs = index.ReadSymbolRecord(loc_specifier_id);
       }
+      if (is_simple_type && !members_info.empty())
+        members_info.back().second =
+            GetTypeSizeForSimpleKind(result.type.getSimpleKind()) - prev_offset;
       auto member_info_ref = llvm::makeArrayRef(members_info);
       result.location =
           MakeEnregisteredLocationExpressionForClass(member_info_ref, module);
       break;
     }
     default:
       // FIXME: Handle other kinds. LLVM only generates the 4 types of records
       // above.

lldb/test/Shell/SymbolFile/NativePDB/Inputs/subfield_register_simple_type.lldbinit

+image lookup -a 0x40102f -v
+quit

lldb/test/Shell/SymbolFile/NativePDB/subfield_register_simple_type.s

+# clang-format off
+# REQUIRES: lld, x86
+
+# RUN: %clang_cl --target=i386-windows-msvc -c /Fo%t.obj %s
+# RUN: lld-link /debug:full /nodefaultlib /entry:main %t.obj /out:%t.exe /base:0x400000
+# RUN: env LLDB_USE_NATIVE_PDB_READER=1 %lldb -f %t.exe -s \
+# RUN:     %p/Inputs/subfield_register_simple_type.lldbinit 2>&1 | FileCheck %s
+
+# This file is compiled from following source file:
+# clang-cl --target=i386-windows-msvc /Z7 /O1 -c /Fa a.cpp
+# __int64 __attribute__((optnone)) bar(__int64 x) { return x; };
+# __int64 foo(__int64 x) {
+#   return bar(x);
+# }
+#
+# int main(int argc, char** argv) {
+#   foo(argc);
+#   return 0;
+# }
+
+# FIXME: The following variable location have wrong register numbers due to
+# https://github.com/llvm/llvm-project/issues/53575. Fix them after resolving
+# the issue.
+
+# CHECK:      (lldb) image lookup -a 0x40102f -v
+# CHECK:      LineEntry: [0x00401026-0x00401039): C:\src\a.cpp:3
+# CHECK-NEXT: Variable: id = {{.*}}, name = "x", type = "int64_t", valid ranges = [0x0040102f-0x00401036), location = DW_OP_reg0 EAX, DW_OP_piece 0x4, DW_OP_reg2 EDX, DW_OP_piece 0x4, decl =
+
+  .text
+  .def  @feat.00;
+  .scl  3;
+  .type 0;
+  .endef
+  .globl  @feat.00
+.set @feat.00, 1
+  .intel_syntax noprefix
+  .file "a.cpp"
+  .def  "?bar@@YA_J_J@Z";
+  .scl  2;
+  .type 32;
+  .endef
+  .section  .text,"xr",one_only,"?bar@@YA_J_J@Z"
+  .globl  "?bar@@YA_J_J@Z"                # -- Begin function ?bar@@YA_J_J@Z
+  .p2align  4, 0x90
+"?bar@@YA_J_J@Z":                       # @"?bar@@YA_J_J@Z"
+Lfunc_begin0:
+  .cv_func_id 0
+  .cv_file  1 "C:\\src\\a.cpp" "CB99424BC3DD1AB059A2DBC6841147F2" 1
+  .cv_loc 0 1 1 0                         # a.cpp:1:0
+  .cv_fpo_proc  "?bar@@YA_J_J@Z" 8
+# %bb.0:                                # %entry
+  push  ebp
+  .cv_fpo_pushreg ebp
+  mov ebp, esp
+  .cv_fpo_setframe  ebp
+  and esp, -8
+  .cv_fpo_stackalign  8
+  sub esp, 8
+  .cv_fpo_stackalloc  8
+  .cv_fpo_endprologue
+  mov  eax, dword ptr [ebp + 8]
+  mov  ecx, dword ptr [ebp + 12]
+  mov dword ptr [esp], eax
+  mov dword ptr [esp + 4], ecx
+Ltmp0:
+  mov eax, dword ptr [esp]
+  mov  edx, dword ptr [esp + 4]
+  mov esp, ebp
+  pop ebp
+  ret
+Ltmp1:
+  .cv_fpo_endproc
+Lfunc_end0:
+                                        # -- End function
+  .def  "?foo@@YA_J_J@Z";
+  .scl  2;
+  .type 32;
+  .endef
+  .section  .text,"xr",one_only,"?foo@@YA_J_J@Z"
+  .globl  "?foo@@YA_J_J@Z"                # -- Begin function ?foo@@YA_J_J@Z
+"?foo@@YA_J_J@Z":                       # @"?foo@@YA_J_J@Z"
+Lfunc_begin1:
+  .cv_func_id 1
+  .cv_fpo_proc  "?foo@@YA_J_J@Z" 8
+# %bb.0:                                # %entry
+  #DEBUG_VALUE: foo:x <- [DW_OP_plus_uconst 4] [$esp+0]
+  .cv_loc 1 1 3 0                         # a.cpp:3:0
+  jmp "?bar@@YA_J_J@Z"                # TAILCALL
+Ltmp2:
+  .cv_fpo_endproc
+Lfunc_end1:
+                                        # -- End function
+  .def  _main;
+  .scl  2;
+  .type 32;
+  .endef
+  .section  .text,"xr",one_only,_main
+  .globl  _main                           # -- Begin function main
+_main:                                  # @main
+Lfunc_begin2:
+  .cv_func_id 2
+  .cv_loc 2 1 6 0                         # a.cpp:6:0
+  .cv_fpo_proc  _main 8
+# %bb.0:                                # %entry
+  #DEBUG_VALUE: main:argv <- [DW_OP_plus_uconst 8] [$esp+0]
+  #DEBUG_VALUE: main:argc <- [DW_OP_plus_uconst 4] [$esp+0]
+  .cv_inline_site_id 3 within 2 inlined_at 1 7 0
+  .cv_loc 3 1 3 0                         # a.cpp:3:0
+  mov  eax, dword ptr [esp + 4]
+  mov ecx, eax
+  sar ecx, 31
+Ltmp3:
+  #DEBUG_VALUE: foo:x <- [DW_OP_LLVM_fragment 0 32] $eax
+  #DEBUG_VALUE: foo:x <- [DW_OP_LLVM_fragment 32 32] $ecx
+  push  ecx
+Ltmp4:
+  push  eax
+  call  "?bar@@YA_J_J@Z"
+Ltmp5:
+  add esp, 8
+Ltmp6:
+  .cv_loc 2 1 8 0                         # a.cpp:8:0
+  xor eax, eax
+  ret
+Ltmp7:
+  .cv_fpo_endproc
+Lfunc_end2:
+                                        # -- End function
+  .section  .drectve,"yn"
+  .ascii  " /DEFAULTLIB:libcmt.lib"
+  .ascii  " /DEFAULTLIB:oldnames.lib"
+  .section  .debug$S,"dr"
+  .p2align  2
+  .long 4                               # Debug section magic
+  .long 241
+  .long Ltmp9-Ltmp8                     # Subsection size
+Ltmp8:
+  .short  Ltmp11-Ltmp10                   # Record length
+Ltmp10:
+  .short  4353                            # Record kind: S_OBJNAME
+  .long 0                               # Signature
+  .asciz  "C:\\src\\a.obj"                # Object name
+  .p2align  2
+Ltmp11:
+  .short  Ltmp13-Ltmp12                   # Record length
+Ltmp12:
+  .short  4412                            # Record kind: S_COMPILE3
+  .long 1                               # Flags and language
+  .short  7                               # CPUType
+  .short  15                              # Frontend version
+  .short  0
+  .short  0
+  .short  0
+  .short  15000                           # Backend version
+  .short  0
+  .short  0
+  .short  0
+  .asciz  "clang version 15.0.0"          # Null-terminated compiler version string
+  .p2align  2
+Ltmp13:
+Ltmp9:
+  .p2align  2
+  .long 246                             # Inlinee lines subsection
+  .long Ltmp15-Ltmp14                   # Subsection size
+Ltmp14:
+  .long 0                               # Inlinee lines signature
+
+                                        # Inlined function foo starts at a.cpp:2
+  .long 4098                            # Type index of inlined function
+  .cv_filechecksumoffset  1               # Offset into filechecksum table
+  .long 2                               # Starting line number
+Ltmp15:
+  .p2align  2
+  .section  .debug$S,"dr",associative,"?bar@@YA_J_J@Z"
+  .p2align  2
+  .long 4                               # Debug section magic
+  .cv_fpo_data  "?bar@@YA_J_J@Z"
+  .long 241                             # Symbol subsection for bar
+  .long Ltmp17-Ltmp16                   # Subsection size
+Ltmp16:
+  .short  Ltmp19-Ltmp18                   # Record length
+Ltmp18:
+  .short  4423                            # Record kind: S_GPROC32_ID
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 0                               # PtrNext
+  .long Lfunc_end0-"?bar@@YA_J_J@Z"     # Code size
+  .long 0                               # Offset after prologue
+  .long 0                               # Offset before epilogue
+  .long 4099                            # Function type index
+  .secrel32 "?bar@@YA_J_J@Z"        # Function section relative address
+  .secidx "?bar@@YA_J_J@Z"                # Function section index
+  .byte 0                               # Flags
+  .asciz  "bar"                           # Function name
+  .p2align  2
+Ltmp19:
+  .short  Ltmp21-Ltmp20                   # Record length
+Ltmp20:
+  .short  4114                            # Record kind: S_FRAMEPROC
+  .long 12                              # FrameSize
+  .long 0                               # Padding
+  .long 0                               # Offset of padding
+  .long 0                               # Bytes of callee saved registers
+  .long 0                               # Exception handler offset
+  .short  0                               # Exception handler section
+  .long 147456                          # Flags (defines frame register)
+  .p2align  2
+Ltmp21:
+  .short  Ltmp23-Ltmp22                   # Record length
+Ltmp22:
+  .short  4414                            # Record kind: S_LOCAL
+  .long 19                              # TypeIndex
+  .short  1                               # Flags
+  .asciz  "x"
+  .p2align  2
+Ltmp23:
+  .cv_def_range   Ltmp0 Ltmp1, reg_rel, 30006, 0, -8
+  .short  2                               # Record length
+  .short  4431                            # Record kind: S_PROC_ID_END
+Ltmp17:
+  .p2align  2
+  .cv_linetable 0, "?bar@@YA_J_J@Z", Lfunc_end0
+  .section  .debug$S,"dr",associative,"?foo@@YA_J_J@Z"
+  .p2align  2
+  .long 4                               # Debug section magic
+  .cv_fpo_data  "?foo@@YA_J_J@Z"
+  .long 241                             # Symbol subsection for foo
+  .long Ltmp25-Ltmp24                   # Subsection size
+Ltmp24:
+  .short  Ltmp27-Ltmp26                   # Record length
+Ltmp26:
+  .short  4423                            # Record kind: S_GPROC32_ID
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 0                               # PtrNext
+  .long Lfunc_end1-"?foo@@YA_J_J@Z"     # Code size
+  .long 0                               # Offset after prologue
+  .long 0                               # Offset before epilogue
+  .long 4098                            # Function type index
+  .secrel32 "?foo@@YA_J_J@Z"        # Function section relative address
+  .secidx "?foo@@YA_J_J@Z"                # Function section index
+  .byte 0                               # Flags
+  .asciz  "foo"                           # Function name
+  .p2align  2
+Ltmp27:
+  .short  Ltmp29-Ltmp28                   # Record length
+Ltmp28:
+  .short  4114                            # Record kind: S_FRAMEPROC
+  .long 0                               # FrameSize
+  .long 0                               # Padding
+  .long 0                               # Offset of padding
+  .long 0                               # Bytes of callee saved registers
+  .long 0                               # Exception handler offset
+  .short  0                               # Exception handler section
+  .long 0                               # Flags (defines frame register)
+  .p2align  2
+Ltmp29:
+  .short  Ltmp31-Ltmp30                   # Record length
+Ltmp30:
+  .short  4414                            # Record kind: S_LOCAL
+  .long 19                              # TypeIndex
+  .short  1                               # Flags
+  .asciz  "x"
+  .p2align  2
+Ltmp31:
+  .cv_def_range   Lfunc_begin1 Lfunc_end1, reg_rel, 30006, 0, 4
+  .short  2                               # Record length
+  .short  4431                            # Record kind: S_PROC_ID_END
+Ltmp25:
+  .p2align  2
+  .cv_linetable 1, "?foo@@YA_J_J@Z", Lfunc_end1
+  .section  .debug$S,"dr",associative,_main
+  .p2align  2
+  .long 4                               # Debug section magic
+  .cv_fpo_data  _main
+  .long 241                             # Symbol subsection for main
+  .long Ltmp33-Ltmp32                   # Subsection size
+Ltmp32:
+  .short  Ltmp35-Ltmp34                   # Record length
+Ltmp34:
+  .short  4423                            # Record kind: S_GPROC32_ID
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 0                               # PtrNext
+  .long Lfunc_end2-_main                # Code size
+  .long 0                               # Offset after prologue
+  .long 0                               # Offset before epilogue
+  .long 4103                            # Function type index
+  .secrel32 _main                   # Function section relative address
+  .secidx _main                           # Function section index
+  .byte 0                               # Flags
+  .asciz  "main"                          # Function name
+  .p2align  2
+Ltmp35:
+  .short  Ltmp37-Ltmp36                   # Record length
+Ltmp36:
+  .short  4114                            # Record kind: S_FRAMEPROC
+  .long 0                               # FrameSize
+  .long 0                               # Padding
+  .long 0                               # Offset of padding
+  .long 0                               # Bytes of callee saved registers
+  .long 0                               # Exception handler offset
+  .short  0                               # Exception handler section
+  .long 0                               # Flags (defines frame register)
+  .p2align  2
+Ltmp37:
+  .short  Ltmp39-Ltmp38                   # Record length
+Ltmp38:
+  .short  4414                            # Record kind: S_LOCAL
+  .long 116                             # TypeIndex
+  .short  1                               # Flags
+  .asciz  "argc"
+  .p2align  2
+Ltmp39:
+  .cv_def_range   Lfunc_begin2 Ltmp4, reg_rel, 30006, 0, 4
+  .short  Ltmp41-Ltmp40                   # Record length
+Ltmp40:
+  .short  4414                            # Record kind: S_LOCAL
+  .long 4100                            # TypeIndex
+  .short  1                               # Flags
+  .asciz  "argv"
+  .p2align  2
+Ltmp41:
+  .cv_def_range   Lfunc_begin2 Ltmp4, reg_rel, 30006, 0, 8
+  .short  Ltmp43-Ltmp42                   # Record length
+Ltmp42:
+  .short  4429                            # Record kind: S_INLINESITE
+  .long 0                               # PtrParent
+  .long 0                               # PtrEnd
+  .long 4098                            # Inlinee type index
+  .cv_inline_linetable  3 1 2 Lfunc_begin2 Lfunc_end2
+  .p2align  2
+Ltmp43:
+  .short  Ltmp45-Ltmp44                   # Record length
+Ltmp44:
+  .short  4414                            # Record kind: S_LOCAL
+  .long 19                              # TypeIndex
+  .short  1                               # Flags
+  .asciz  "x"
+  .p2align  2
+Ltmp45:
+  .cv_def_range   Ltmp3 Ltmp5, subfield_reg, 17, 0
+  .cv_def_range   Ltmp3 Ltmp5, subfield_reg, 18, 4
+  .short  2                               # Record length
+  .short  4430                            # Record kind: S_INLINESITE_END
+  .short  2                               # Record length
+  .short  4431                            # Record kind: S_PROC_ID_END
+Ltmp33:
+  .p2align  2
+  .cv_linetable 2, _main, Lfunc_end2
+  .section  .debug$S,"dr"
+  .cv_filechecksums                       # File index to string table offset subsection
+  .cv_stringtable                         # String table
+  .long 241
+  .long Ltmp47-Ltmp46                   # Subsection size
+Ltmp46:
+  .short  Ltmp49-Ltmp48                   # Record length
+Ltmp48:
+  .short  4428                            # Record kind: S_BUILDINFO
+  .long 4109                            # LF_BUILDINFO index
+  .p2align  2
+Ltmp49:
+Ltmp47:
+  .p2align  2
+  .section  .debug$T,"dr"
+  .p2align  2
+  .long 4                               # Debug section magic
+  # ArgList (0x1000)
+  .short  0xa                             # Record length
+  .short  0x1201                          # Record kind: LF_ARGLIST
+  .long 0x1                             # NumArgs
+  .long 0x13                            # Argument: __int64
+  # Procedure (0x1001)
+  .short  0xe                             # Record length
+  .short  0x1008                          # Record kind: LF_PROCEDURE
+  .long 0x13                            # ReturnType: __int64
+  .byte 0x0                             # CallingConvention: NearC
+  .byte 0x0                             # FunctionOptions
+  .short  0x1                             # NumParameters
+  .long 0x1000                          # ArgListType: (__int64)
+  # FuncId (0x1002)
+  .short  0xe                             # Record length
+  .short  0x1601                          # Record kind: LF_FUNC_ID
+  .long 0x0                             # ParentScope
+  .long 0x1001                          # FunctionType: __int64 (__int64)
+  .asciz  "foo"                           # Name
+  # FuncId (0x1003)
+  .short  0xe                             # Record length
+  .short  0x1601                          # Record kind: LF_FUNC_ID
+  .long 0x0                             # ParentScope
+  .long 0x1001                          # FunctionType: __int64 (__int64)
+  .asciz  "bar"                           # Name
+  # Pointer (0x1004)
+  .short  0xa                             # Record length
+  .short  0x1002                          # Record kind: LF_POINTER
+  .long 0x470                           # PointeeType: char*
+  .long 0x800a                          # Attrs: [ Type: Near32, Mode: Pointer, SizeOf: 4 ]
+  # ArgList (0x1005)
+  .short  0xe                             # Record length
+  .short  0x1201                          # Record kind: LF_ARGLIST
+  .long 0x2                             # NumArgs
+  .long 0x74                            # Argument: int
+  .long 0x1004                          # Argument: char**
+  # Procedure (0x1006)
+  .short  0xe                             # Record length
+  .short  0x1008                          # Record kind: LF_PROCEDURE
+  .long 0x74                            # ReturnType: int
+  .byte 0x0                             # CallingConvention: NearC
+  .byte 0x0                             # FunctionOptions
+  .short  0x2                             # NumParameters
+  .long 0x1005                          # ArgListType: (int, char**)
+  # FuncId (0x1007)
+  .short  0x12                            # Record length
+  .short  0x1601                          # Record kind: LF_FUNC_ID
+  .long 0x0                             # ParentScope
+  .long 0x1006                          # FunctionType: int (int, char**)
+  .asciz  "main"                          # Name
+  .byte 243
+  .byte 242
+  .byte 241
+  # StringId (0x1008)
+  .short  0xe                             # Record length
+  .short  0x1605                          # Record kind: LF_STRING_ID
+  .long 0x0                             # Id
+  .asciz  "C:\\src"                       # StringData
+  .byte 241
+  # StringId (0x1009)
+  .short  0xe                             # Record length
+  .short  0x1605                          # Record kind: LF_STRING_ID
+  .long 0x0                             # Id
+  .asciz  "a.cpp"                         # StringData
+  .byte 242
+  .byte 241