DWARFVerifier: validate information in name index entries
Summary:
This patch add checks to verify that the information in the name index
entries is consistent with the debug_info section. Specifically, we
check that entries point to valid DIEs, and their names, tags, and
compile units match the information in the debug_info sections.
These checks are only run if the previous checks did not find any errors
in the name index headers. Attempting to proceed with the checks anyway
would likely produce a lot of spurious errors and the verification code
would need to be very careful to avoid crashing.
I also add a couple of more checks to the abbreviation-validation code
to verify that some attributes are always present (an index without a
DW_IDX_die_offset attribute is fairly useless).
The entry verification works only on indexes without any type units - I
haven't attempted to extend it to type units, as we don't even have a
DWARF v5-compatible type unit generator at the moment.
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45323
llvm-svn: 329392
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h
index 27f11ca..7cc2825 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h
@@ -283,6 +283,11 @@
Entry(const NameIndex &NameIdx, const Abbrev &Abbr);
+ public:
+ Optional<uint64_t> getCUOffset() const override;
+ Optional<uint64_t> getDIESectionOffset() const override;
+ Optional<dwarf::Tag> getTag() const override { return tag(); }
+
/// Returns the Index into the Compilation Unit list of the owning Name
/// Index or None if this Accelerator Entry does not have an associated
/// Compilation Unit. It is up to the user to verify that the returned Index
@@ -293,11 +298,6 @@
/// DW_IDX_compile_unit attribute.
Optional<uint64_t> getCUIndex() const;
- public:
- Optional<uint64_t> getCUOffset() const override;
- Optional<uint64_t> getDIESectionOffset() const override;
- Optional<dwarf::Tag> getTag() const override { return tag(); }
-
/// .debug_names-specific getter, which always succeeds (DWARF v5 index
/// entries always have a tag).
dwarf::Tag tag() const { return Abbr->Tag; }
@@ -319,7 +319,6 @@
friend class ValueIterator;
};
-private:
/// Error returned by NameIndex::getEntry to report it has reached the end of
/// the entry list.
class SentinelError : public ErrorInfo<SentinelError> {
@@ -330,6 +329,7 @@
std::error_code convertToErrorCode() const override;
};
+private:
/// DenseMapInfo for struct Abbrev.
struct AbbrevMapInfo {
static Abbrev getEmptyKey();
@@ -373,8 +373,6 @@
uint32_t EntryOffsetsBase;
uint32_t EntriesBase;
- Expected<Entry> getEntry(uint32_t *Offset) const;
-
void dumpCUs(ScopedPrinter &W) const;
void dumpLocalTUs(ScopedPrinter &W) const;
void dumpForeignTUs(ScopedPrinter &W) const;
@@ -429,6 +427,8 @@
return Abbrevs;
}
+ Expected<Entry> getEntry(uint32_t *Offset) const;
+
llvm::Error extract();
uint32_t getUnitOffset() const { return Base; }
uint32_t getNextUnitOffset() const { return Base + 4 + Hdr.UnitLength; }
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
index afaa299..85164ec 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
@@ -240,6 +240,8 @@
unsigned verifyNameIndexAttribute(const DWARFDebugNames::NameIndex &NI,
const DWARFDebugNames::Abbrev &Abbr,
DWARFDebugNames::AttributeEncoding AttrEnc);
+ unsigned verifyNameIndexEntries(const DWARFDebugNames::NameIndex &NI,
+ uint32_t Name, const DataExtractor &StrData);
/// Verify that the DWARF v5 accelerator table is valid.
///
@@ -251,6 +253,8 @@
/// - The buckets have a valid index, or they are empty.
/// - All names are reachable via the hash table (they have the correct hash,
/// and the hash is in the correct bucket).
+ /// - Information in the index entries is consistent with the debug_info
+ /// section DIEs.
///
/// \param AccelSection section containing the acceleration table
/// \param StrData string section
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp b/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
index fccff27..9d1d070 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
@@ -601,7 +601,7 @@
DWARFDebugNames::NameIndex::getEntry(uint32_t *Offset) const {
const DWARFDataExtractor &AS = Section.AccelSection;
if (!AS.isValidOffset(*Offset))
- return make_error<StringError>("Incorrectly terminated entry list",
+ return make_error<StringError>("Incorrectly terminated entry list.",
inconvertibleErrorCode());
uint32_t AbbrevCode = AS.getULEB128(Offset);
@@ -610,7 +610,7 @@
const auto AbbrevIt = Abbrevs.find_as(AbbrevCode);
if (AbbrevIt == Abbrevs.end())
- return make_error<StringError>("Invalid abbreviation",
+ return make_error<StringError>("Invalid abbreviation.",
inconvertibleErrorCode());
Entry E(*this, *AbbrevIt);
@@ -618,7 +618,7 @@
dwarf::FormParams FormParams = {Hdr.Version, 0, dwarf::DwarfFormat::DWARF32};
for (auto &Value : E.Values) {
if (!Value.extractValue(AS, Offset, FormParams))
- return make_error<StringError>("Error extracting index attribute values",
+ return make_error<StringError>("Error extracting index attribute values.",
inconvertibleErrorCode());
}
return std::move(E);
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index 92d956c..73aa501 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -1000,6 +1000,13 @@
unsigned
DWARFVerifier::verifyNameIndexAbbrevs(const DWARFDebugNames::NameIndex &NI) {
+ if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0) {
+ warn() << formatv("Name Index @ {0:x}: Verifying indexes of type units is "
+ "not currently supported.\n",
+ NI.getUnitOffset());
+ return 0;
+ }
+
unsigned NumErrors = 0;
for (const auto &Abbrev : NI.getAbbrevs()) {
StringRef TagName = dwarf::TagString(Abbrev.Tag);
@@ -1019,10 +1026,122 @@
}
NumErrors += verifyNameIndexAttribute(NI, Abbrev, AttrEnc);
}
+
+ if (NI.getCUCount() > 1 && !Attributes.count(dwarf::DW_IDX_compile_unit)) {
+ error() << formatv("NameIndex @ {0:x}: Indexing multiple compile units "
+ "and abbreviation {1:x} has no {2} attribute.\n",
+ NI.getUnitOffset(), Abbrev.Code,
+ dwarf::DW_IDX_compile_unit);
+ ++NumErrors;
+ }
+ if (!Attributes.count(dwarf::DW_IDX_die_offset)) {
+ error() << formatv(
+ "NameIndex @ {0:x}: Abbreviation {1:x} has no {2} attribute.\n",
+ NI.getUnitOffset(), Abbrev.Code, dwarf::DW_IDX_die_offset);
+ ++NumErrors;
+ }
}
return NumErrors;
}
+static SmallVector<StringRef, 2> getNames(const DWARFDie &DIE) {
+ SmallVector<StringRef, 2> Result;
+ if (const char *Str = DIE.getName(DINameKind::ShortName))
+ Result.emplace_back(Str);
+ else if (DIE.getTag() == dwarf::DW_TAG_namespace)
+ Result.emplace_back("(anonymous namespace)");
+
+ if (const char *Str = DIE.getName(DINameKind::LinkageName)) {
+ if (Result.empty() || Result[0] != Str)
+ Result.emplace_back(Str);
+ }
+
+ return Result;
+}
+
+unsigned
+DWARFVerifier::verifyNameIndexEntries(const DWARFDebugNames::NameIndex &NI,
+ uint32_t Name,
+ const DataExtractor &StrData) {
+ // Verifying type unit indexes not supported.
+ if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0)
+ return 0;
+
+ DWARFDebugNames::NameTableEntry NTE = NI.getNameTableEntry(Name);
+ const char *CStr = StrData.getCStr(&NTE.StringOffset);
+ if (!CStr) {
+ error() << formatv(
+ "Name Index @ {0:x}: Unable to get string associated with name {1}.\n",
+ NI.getUnitOffset(), Name);
+ return 1;
+ }
+ StringRef Str(CStr);
+
+ unsigned NumErrors = 0;
+ unsigned NumEntries = 0;
+ uint32_t EntryID = NTE.EntryOffset;
+ Expected<DWARFDebugNames::Entry> EntryOr = NI.getEntry(&NTE.EntryOffset);
+ for (; EntryOr; ++NumEntries, EntryID = NTE.EntryOffset,
+ EntryOr = NI.getEntry(&NTE.EntryOffset)) {
+ uint32_t CUIndex = *EntryOr->getCUIndex();
+ if (CUIndex > NI.getCUCount()) {
+ error() << formatv("Name Index @ {0:x}: Entry @ {1:x} contains an "
+ "invalid CU index ({2}).\n",
+ NI.getUnitOffset(), EntryID, CUIndex);
+ ++NumErrors;
+ continue;
+ }
+ uint32_t CUOffset = NI.getCUOffset(CUIndex);
+ uint64_t DIEOffset = *EntryOr->getDIESectionOffset();
+ DWARFDie DIE = DCtx.getDIEForOffset(DIEOffset);
+ if (!DIE) {
+ error() << formatv("Name Index @ {0:x}: Entry @ {1:x} references a "
+ "non-existing DIE @ {2:x}.\n",
+ NI.getUnitOffset(), EntryID, DIEOffset);
+ ++NumErrors;
+ continue;
+ }
+ if (DIE.getDwarfUnit()->getOffset() != CUOffset) {
+ error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched CU of "
+ "DIE @ {2:x}: index - {3:x}; debug_info - {4:x}.\n",
+ NI.getUnitOffset(), EntryID, DIEOffset, CUOffset,
+ DIE.getDwarfUnit()->getOffset());
+ ++NumErrors;
+ }
+ if (DIE.getTag() != EntryOr->tag()) {
+ error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Tag of "
+ "DIE @ {2:x}: index - {3}; debug_info - {4}.\n",
+ NI.getUnitOffset(), EntryID, DIEOffset, EntryOr->tag(),
+ DIE.getTag());
+ ++NumErrors;
+ }
+
+ auto EntryNames = getNames(DIE);
+ if (!is_contained(EntryNames, Str)) {
+ error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Name "
+ "of DIE @ {2:x}: index - {3}; debug_info - {4}.\n",
+ NI.getUnitOffset(), EntryID, DIEOffset, Str,
+ make_range(EntryNames.begin(), EntryNames.end()));
+ }
+ }
+ handleAllErrors(EntryOr.takeError(),
+ [&](const DWARFDebugNames::SentinelError &) {
+ if (NumEntries > 0)
+ return;
+ error() << formatv("Name Index @ {0:x}: Name {1} ({2}) is "
+ "not associated with any entries.\n",
+ NI.getUnitOffset(), Name, Str);
+ ++NumErrors;
+ },
+ [&](const ErrorInfoBase &Info) {
+ error() << formatv(
+ "Name Index @ {0:x}: Name {1} ({2}): {3}\n",
+ NI.getUnitOffset(), Name, Str, Info.message());
+ ++NumErrors;
+ });
+ return NumErrors;
+}
+
unsigned DWARFVerifier::verifyDebugNames(const DWARFSection &AccelSection,
const DataExtractor &StrData) {
unsigned NumErrors = 0;
@@ -1045,6 +1164,13 @@
for (const auto &NI : AccelTable)
NumErrors += verifyNameIndexAbbrevs(NI);
+ // Don't attempt Entry validation if any of the previous checks found errors
+ if (NumErrors > 0)
+ return NumErrors;
+ for (const auto &NI : AccelTable)
+ for (uint64_t Name = 1; Name <= NI.getNameCount(); ++Name)
+ NumErrors += verifyNameIndexEntries(NI, Name, StrData);
+
return NumErrors;
}
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-abbrev-forms.s b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-abbrev-forms.s
index 910431c..cba6cb6 100644
--- a/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-abbrev-forms.s
+++ b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-abbrev-forms.s
@@ -8,6 +8,8 @@
# CHECK: error: NameIndex @ 0x0: Abbreviation 0x4 contains multiple DW_IDX_die_offset attributes.
# CHECK: NameIndex @ 0x0: Abbreviation 0x1: DW_IDX_die_offset uses an unknown form: DW_FORM_unknown_1fff.
# CHECK: warning: NameIndex @ 0x0: Abbreviation 0x3 references an unknown tag: DW_TAG_unknown_8080.
+# CHECK: error: NameIndex @ 0x0: Abbreviation 0x5 has no DW_IDX_die_offset attribute.
+# CHECK: error: NameIndex @ 0x55: Indexing multiple compile units and abbreviation 0x1 has no DW_IDX_compile_unit attribute.
.section .debug_str,"MS",@progbits,1
.Lstring_producer:
@@ -39,6 +41,30 @@
.byte 0 # End Of Children Mark
.Lcu_end0:
+.Lcu_begin1:
+ .long .Lcu_end1-.Lcu_start1 # Length of Unit
+.Lcu_start1:
+ .short 4 # DWARF version number
+ .long .Lsection_abbrev # Offset Into Abbrev. Section
+ .byte 8 # Address Size (in bytes)
+ .byte 1 # Abbrev [1] DW_TAG_compile_unit
+ .long .Lstring_producer # DW_AT_producer
+ .short 12 # DW_AT_language
+ .byte 0 # End Of Children Mark
+.Lcu_end1:
+
+.Lcu_begin2:
+ .long .Lcu_end2-.Lcu_start2 # Length of Unit
+.Lcu_start2:
+ .short 4 # DWARF version number
+ .long .Lsection_abbrev # Offset Into Abbrev. Section
+ .byte 8 # Address Size (in bytes)
+ .byte 1 # Abbrev [1] DW_TAG_compile_unit
+ .long .Lstring_producer # DW_AT_producer
+ .short 12 # DW_AT_language
+ .byte 0 # End Of Children Mark
+.Lcu_end2:
+
.section .debug_names,"",@progbits
.long .Lnames_end0-.Lnames_start0 # Header: contribution length
.Lnames_start0:
@@ -87,6 +113,36 @@
.byte 17 # DW_FORM_ref1
.byte 0 # End of abbrev
.byte 0 # End of abbrev
+ .byte 5 # Abbrev code
+ .byte 46 # DW_TAG_subprogram
+ .byte 4 # DW_IDX_parent
+ .byte 5 # DW_FORM_data2
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev
.byte 0 # End of abbrev list
.Lnames_abbrev_end0:
.Lnames_end0:
+
+ .long .Lnames_end1-.Lnames_start1 # Header: contribution length
+.Lnames_start1:
+ .short 5 # Header: version
+ .short 0 # Header: padding
+ .long 2 # Header: compilation unit count
+ .long 0 # Header: local type unit count
+ .long 0 # Header: foreign type unit count
+ .long 0 # Header: bucket count
+ .long 0 # Header: name count
+ .long .Lnames_abbrev_end1-.Lnames_abbrev_start1 # Header: abbreviation table size
+ .long 0 # Header: augmentation length
+ .long .Lcu_begin1 # Compilation unit 0
+ .long .Lcu_begin2 # Compilation unit 1
+.Lnames_abbrev_start1:
+ .byte 1 # Abbrev code
+ .byte 46 # DW_TAG_subprogram
+ .byte 3 # DW_IDX_die_offset
+ .byte 17 # DW_FORM_ref1
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev list
+.Lnames_abbrev_end1:
+.Lnames_end1:
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-entries.s b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-entries.s
new file mode 100644
index 0000000..4ee2b0a
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-entries.s
@@ -0,0 +1,188 @@
+# RUN: llvm-mc -triple x86_64-pc-linux %s -filetype=obj -o - | not llvm-dwarfdump -verify - | FileCheck %s
+
+# CHECK: error: Name Index @ 0x0: Unable to get string associated with name 1.
+# CHECK: error: Name Index @ 0x0: Entry @ 0x73 contains an invalid CU index (47).
+# CHECK: error: Name Index @ 0x0: Entry @ 0x79 references a non-existing DIE @ 0x3fa.
+# CHECK: error: Name Index @ 0x0: Entry @ 0x85: mismatched CU of DIE @ 0x30: index - 0x0; debug_info - 0x1e.
+# CHECK: error: Name Index @ 0x0: Entry @ 0x8b: mismatched Tag of DIE @ 0x17: index - DW_TAG_subprogram; debug_info - DW_TAG_variable.
+# CHECK: error: Name Index @ 0x0: Entry @ 0x91: mismatched Name of DIE @ 0x35: index - foo; debug_info - bar, _Z3bar.
+# CHECK: error: Name Index @ 0x0: Name 2 (foo): Incorrectly terminated entry list.
+# CHECK: error: Name Index @ 0x0: Name 3 (bar) is not associated with any entries.
+# CHECK: error: Name Index @ 0x0: Entry @ 0x69: mismatched Name of DIE @ 0x1c: index - (pseudonymous namespace); debug_info - (anonymous namespace).
+
+ .section .debug_str,"MS",@progbits,1
+.Lstring_foo:
+ .asciz "foo"
+.Lstring_bar:
+ .asciz "bar"
+.Lstring_bar_mangled:
+ .asciz "_Z3bar"
+.Lstring_pseudo_namespace:
+ .asciz "(pseudonymous namespace)"
+.Lstring_producer:
+ .asciz "Hand-written dwarf"
+
+ .section .debug_abbrev,"",@progbits
+.Lsection_abbrev:
+ .byte 1 # Abbreviation Code
+ .byte 17 # DW_TAG_compile_unit
+ .byte 1 # DW_CHILDREN_yes
+ .byte 37 # DW_AT_producer
+ .byte 14 # DW_FORM_strp
+ .byte 19 # DW_AT_language
+ .byte 5 # DW_FORM_data2
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 2 # Abbreviation Code
+ .byte 46 # DW_TAG_subprogram
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 63 # DW_AT_external
+ .byte 25 # DW_FORM_flag_present
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 3 # Abbreviation Code
+ .byte 52 # DW_TAG_variable
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 4 # Abbreviation Code
+ .byte 57 # DW_TAG_namespace
+ .byte 0 # DW_CHILDREN_no
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 5 # Abbreviation Code
+ .byte 52 # DW_TAG_variable
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 110 # DW_AT_linkage_name
+ .byte 14 # DW_FORM_strp
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 0 # EOM(3)
+
+ .section .debug_info,"",@progbits
+.Lcu_begin0:
+ .long .Lcu_end0-.Lcu_start0 # Length of Unit
+.Lcu_start0:
+ .short 4 # DWARF version number
+ .long .Lsection_abbrev # Offset Into Abbrev. Section
+ .byte 8 # Address Size (in bytes)
+ .byte 1 # Abbrev [1] DW_TAG_compile_unit
+ .long .Lstring_producer # DW_AT_producer
+ .short 12 # DW_AT_language
+.Ldie_foo:
+ .byte 2 # Abbrev [2] DW_TAG_subprogram
+ .long .Lstring_foo # DW_AT_name
+ # DW_AT_external
+.Ldie_foo_var:
+ .byte 3 # Abbrev [3] DW_TAG_variable
+ .long .Lstring_foo # DW_AT_name
+.Ldie_namespace:
+ .byte 4 # Abbrev [3] DW_TAG_namespace
+ .byte 0 # End Of Children Mark
+.Lcu_end0:
+
+.Lcu_begin1:
+ .long .Lcu_end1-.Lcu_start1 # Length of Unit
+.Lcu_start1:
+ .short 4 # DWARF version number
+ .long .Lsection_abbrev # Offset Into Abbrev. Section
+ .byte 8 # Address Size (in bytes)
+ .byte 1 # Abbrev [1] DW_TAG_compile_unit
+ .long .Lstring_producer # DW_AT_producer
+ .short 12 # DW_AT_language
+.Ldie_foo2:
+ .byte 2 # Abbrev [2] DW_TAG_subprogram
+ .long .Lstring_foo # DW_AT_name
+ # DW_AT_external
+.Ldie_bar_linkage:
+ .byte 5 # Abbrev [2] DW_TAG_variable
+ .long .Lstring_bar # DW_AT_name
+ .long .Lstring_bar_mangled # DW_AT_linkage_name
+ .byte 0 # End Of Children Mark
+.Lcu_end1:
+
+
+ .section .debug_names,"",@progbits
+ .long .Lnames_end0-.Lnames_start0 # Header: contribution length
+.Lnames_start0:
+ .short 5 # Header: version
+ .short 0 # Header: padding
+ .long 2 # Header: compilation unit count
+ .long 0 # Header: local type unit count
+ .long 0 # Header: foreign type unit count
+ .long 0 # Header: bucket count
+ .long 4 # Header: name count
+ .long .Lnames_abbrev_end0-.Lnames_abbrev_start0 # Header: abbreviation table size
+ .long 0 # Header: augmentation length
+ .long .Lcu_begin0 # Compilation unit 0
+ .long .Lcu_begin1 # Compilation unit 1
+ .long .Lstring_foo+1000 # String 1: <broken>
+ .long .Lstring_foo # String 2: foo
+ .long .Lstring_bar # String 3: bar
+ .long .Lstring_pseudo_namespace # String 4: (pseudonymous namespace)
+ .long .Lnames0-.Lnames_entries0 # Offset 1
+ .long .Lnames0-.Lnames_entries0 # Offset 2
+ .long .Lnames1-.Lnames_entries0 # Offset 3
+ .long .Lnames2-.Lnames_entries0 # Offset 4
+.Lnames_abbrev_start0:
+ .byte 46 # Abbrev code
+ .byte 46 # DW_TAG_subprogram
+ .byte 1 # DW_IDX_compile_unit
+ .byte 11 # DW_FORM_data1
+ .byte 3 # DW_IDX_die_offset
+ .byte 19 # DW_FORM_ref4
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev
+ .byte 57 # Abbrev code
+ .byte 57 # DW_TAG_namespace
+ .byte 1 # DW_IDX_compile_unit
+ .byte 11 # DW_FORM_data1
+ .byte 3 # DW_IDX_die_offset
+ .byte 19 # DW_FORM_ref4
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev
+ .byte 52 # Abbrev code
+ .byte 52 # DW_TAG_variable
+ .byte 1 # DW_IDX_compile_unit
+ .byte 11 # DW_FORM_data1
+ .byte 3 # DW_IDX_die_offset
+ .byte 19 # DW_FORM_ref4
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev list
+.Lnames_abbrev_end0:
+.Lnames_entries0:
+.Lnames1:
+ .long 0 # End of list: bar
+.Lnames2:
+ .byte 57 # Abbrev code
+ .byte 0 # DW_IDX_compile_unit
+ .long .Ldie_namespace-.Lcu_begin0 # DW_IDX_die_offset
+ .long 0 # End of list: (pseudonymous namespace)
+.Lnames0:
+ .byte 46 # Abbrev code
+ .byte 47 # DW_IDX_compile_unit
+ .long .Ldie_foo-.Lcu_begin0 # DW_IDX_die_offset
+ .byte 46 # Abbrev code
+ .byte 0 # DW_IDX_compile_unit
+ .long .Ldie_foo-.Lcu_begin0+1000 # DW_IDX_die_offset
+ .byte 46 # Abbrev code
+ .byte 0 # DW_IDX_compile_unit
+ .long .Ldie_foo-.Lcu_begin0 # DW_IDX_die_offset
+ .byte 46 # Abbrev code
+ .byte 0 # DW_IDX_compile_unit
+ .long .Ldie_foo2-.Lcu_begin0 # DW_IDX_die_offset
+ .byte 46 # Abbrev code
+ .byte 0 # DW_IDX_compile_unit
+ .long .Ldie_foo_var-.Lcu_begin0 # DW_IDX_die_offset
+ .byte 52 # Abbrev code
+ .byte 1 # DW_IDX_compile_unit
+ .long .Ldie_bar_linkage-.Lcu_begin1 # DW_IDX_die_offset
+ #.long 0 # End of list deliberately missing
+.Lnames_end0: