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Differential D98826

[lldb] DWZ 14/17: Workaround DWZ bug dropping DW_TAG_namespace::DW_AT_export_symbols
AbandonedPublic

Authored by jankratochvil on Mar 17 2021, 3:59 PM.

Details

Reviewers
labath
shafik
Summary

I have filed for dwz tool: Multifile drops DW_TAG_namespace::DW_AT_export_symbols
Not sure if they fix it but nonetheless there are already corrupted debuginfos out there and it is easy to workaround.

Diff Detail

Event Timeline

jankratochvil created this revision.Mar 17 2021, 3:59 PM
Herald added a reviewer: shafik. · View Herald TranscriptMar 17 2021, 3:59 PM
Herald added a subscriber: JDevlieghere. · View Herald Transcript
jankratochvil requested review of this revision.Mar 17 2021, 3:59 PM
jankratochvil added a parent revision: D96240: [lldb] DWZ 13/17: Main functionality.
jankratochvil added a child revision: D96241: [lldb] DWZ 15/17: New testsuite category 'dwz'.
Harbormaster completed remote builds in B94346: Diff 331402.Mar 17 2021, 4:58 PM
jankratochvil updated this revision to Diff 333692.Mar 27 2021, 3:18 PM

testcase: DWZ is unsupported on OSX.

Harbormaster completed remote builds in B95979: Diff 333692.Mar 27 2021, 3:18 PM
jankratochvil updated this revision to Diff 374776.Sep 24 2021, 2:58 AM
jankratochvil retitled this revision from [lldb] DWZ 6/9: Workaround DWZ bug dropping DW_TAG_namespace::DW_AT_export_symbols to [lldb] DWZ 14/17: Workaround DWZ bug dropping DW_TAG_namespace::DW_AT_export_symbols.
jankratochvil edited the summary of this revision. (Show Details)

My question about upstreaming of this patchset.

Harbormaster completed remote builds in B125513: Diff 374776.Sep 24 2021, 2:59 AM
jankratochvil abandoned this revision.Sep 27 2021, 9:34 AM

I will be no longer involved with this patchset.

Revision Contents

PathSize
lldb/
source/
Plugins/
SymbolFile/
DWARF/
1 line
31 lines
test/
Shell/
SymbolFile/
DWARF/
198 lines

Diff 374776

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.h

Show First 20 Lines • Show All 204 Lines • ▼ Show 20 Lines lldb::TypeSP ParseEnum(const lldb_private::SymbolContext &sc,
const DWARFDIE &die, ParsedDWARFTypeAttributes &attrs); const DWARFDIE &die, ParsedDWARFTypeAttributes &attrs);
lldb::TypeSP ParseSubroutine(const DWARFDIE &die, lldb::TypeSP ParseSubroutine(const DWARFDIE &die,
ParsedDWARFTypeAttributes &attrs); ParsedDWARFTypeAttributes &attrs);
// FIXME: attrs should be passed as a const reference. // FIXME: attrs should be passed as a const reference.
lldb::TypeSP ParseArrayType(const DWARFDIE &die, lldb::TypeSP ParseArrayType(const DWARFDIE &die,
ParsedDWARFTypeAttributes &attrs); ParsedDWARFTypeAttributes &attrs);
lldb::TypeSP ParsePointerToMemberType(const DWARFDIE &die, lldb::TypeSP ParsePointerToMemberType(const DWARFDIE &die,
const ParsedDWARFTypeAttributes &attrs); const ParsedDWARFTypeAttributes &attrs);
bool NamespaceDIEIsInline(const DWARFDIE &nsdie) const;
}; };
/// Parsed form of all attributes that are relevant for type reconstruction. /// Parsed form of all attributes that are relevant for type reconstruction.
/// Some attributes are relevant for all kinds of types (declaration), while /// Some attributes are relevant for all kinds of types (declaration), while
/// others are only meaningful to a specific type (is_virtual) /// others are only meaningful to a specific type (is_virtual)
struct ParsedDWARFTypeAttributes { struct ParsedDWARFTypeAttributes {
explicit ParsedDWARFTypeAttributes(const DWARFDIE &die); explicit ParsedDWARFTypeAttributes(const DWARFDIE &die);
Show All 30 Lines

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp

Show First 20 Lines • Show All 3,384 Lines • ▼ Show 20 Lines if (!decl) {
LinkDeclContextToDIE((clang::DeclContext *)decl, die); LinkDeclContextToDIE((clang::DeclContext *)decl, die);
} }
return decl; return decl;
} }
return nullptr; return nullptr;
} }
// Workaround for DWZ tool bug producing corrupted DWARF:
// Multifile drops DW_TAG_namespace::DW_AT_export_symbols
// https://sourceware.org/bugzilla/show_bug.cgi?id=27572
bool DWARFASTParserClang::NamespaceDIEIsInline(const DWARFDIE &nsdie) const {
if (nsdie.GetAttributeValueAsUnsigned(DW_AT_export_symbols, 0) != 0)
return true;
if (nsdie.GetCU()->GetUnitDIEOnly().Tag() != DW_TAG_partial_unit)
return false;
llvm::SmallVector<const char *, 4> namevec;
for (DWARFDIE myname = nsdie; myname.IsValid(); myname = myname.GetParent())
if (myname.Tag() == DW_TAG_namespace)
namevec.push_back(myname.GetName());
lldbassert(!namevec.empty());
DWARFDIE finddie = nsdie.GetMainCU()->DIE(nsdie.GetMainCU());
while (!namevec.empty()) {
llvm::StringRef findname = namevec.back();
namevec.pop_back();
for (finddie = finddie.GetFirstChild();; finddie = finddie.GetSibling()) {
if (!finddie.IsValid())
return false;
if (finddie.Tag() == DW_TAG_namespace &&
findname == llvm::StringRef(finddie.GetName()))
break;
}
}
return finddie.GetAttributeValueAsUnsigned(DW_AT_export_symbols, 0) != 0;
}
clang::NamespaceDecl * clang::NamespaceDecl *
DWARFASTParserClang::ResolveNamespaceDIE(const DWARFDIE &die) { DWARFASTParserClang::ResolveNamespaceDIE(const DWARFDIE &die) {
if (die && die.Tag() == DW_TAG_namespace) { if (die && die.Tag() == DW_TAG_namespace) {
// See if we already parsed this namespace DIE and associated it with a // See if we already parsed this namespace DIE and associated it with a
// uniqued namespace declaration // uniqued namespace declaration
clang::NamespaceDecl *namespace_decl = static_cast<clang::NamespaceDecl *>( clang::NamespaceDecl *namespace_decl = static_cast<clang::NamespaceDecl *>(
m_dieref_to_decl_ctx[*die.GetDIERef()]); m_dieref_to_decl_ctx[*die.GetDIERef()]);
if (namespace_decl) if (namespace_decl)
return namespace_decl; return namespace_decl;
else { else {
const char *namespace_name = die.GetName(); const char *namespace_name = die.GetName();
clang::DeclContext *containing_decl_ctx = clang::DeclContext *containing_decl_ctx =
GetClangDeclContextContainingDIE(die, nullptr); GetClangDeclContextContainingDIE(die, nullptr);
bool is_inline = bool is_inline = NamespaceDIEIsInline(die);
die.GetAttributeValueAsUnsigned(DW_AT_export_symbols, 0) != 0;
namespace_decl = m_ast.GetUniqueNamespaceDeclaration( namespace_decl = m_ast.GetUniqueNamespaceDeclaration(
namespace_name, containing_decl_ctx, GetOwningClangModule(die), namespace_name, containing_decl_ctx, GetOwningClangModule(die),
is_inline); is_inline);
Log *log = Log *log =
nullptr; // (LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO)); nullptr; // (LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO));
if (log) { if (log) {
SymbolFileDWARF *dwarf = die.GetMainDWARF(); SymbolFileDWARF *dwarf = die.GetMainDWARF();
▲ Show 20 Lines • Show All 345 Lines • Show Last 20 Lines

lldb/test/Shell/SymbolFile/DWARF/dwz-namespace-inline.s

  • This file was added.
PropertyOld ValueNew Value
File Modenull100755
# Workaround for DWZ tool bug producing corrupted DWARF:
# Multifile drops DW_TAG_namespace::DW_AT_export_symbols
# https://sourceware.org/bugzilla/show_bug.cgi?id=27572
# REQUIRES: target-x86_64, system-linux, native
# RUN: %clang_host -o %t %s
# RUN: %lldb %t -o 'b main' -o r -o 'p N::A::m' -o 'p N::m' \
# RUN: -o exit | FileCheck %s
# CHECK-LABEL: (lldb) p N::A::m
# CHECK-NEXT: (int (*)()) $0 = 0x{{.*}}`N::A::m())
# CHECK-LABEL: (lldb) p N::m
# Failing case was:
# error: <user expression 1>:1:4: no member named 'm' in namespace 'N'
# CHECK-NEXT: (int (*)()) $1 = 0x{{.*}}`N::A::m())
.text
.globl main # -- Begin function main
.type main,@function
main: # @main
.Lfunc_begin0:
pushq %rbp
movq %rsp, %rbp
popq %rbp
retq
.Lfunc_end0:
.size main, .Lfunc_end0-main
# -- End function
.type _ZN1N1AL1mEv,@function
_ZN1N1AL1mEv: # @_ZN1N1AL1mEv
.Lfunc_begin1:
pushq %rbp
movq %rsp, %rbp
movl $42, %eax
popq %rbp
retq
.Lfunc_end1:
.size _ZN1N1AL1mEv, .Lfunc_end1-_ZN1N1AL1mEv
# -- End function
.section .debug_abbrev,"",@progbits
.Labbrev0:
.byte 1 # Abbreviation Code
.byte 17 # DW_TAG_compile_unit
.byte 1 # DW_CHILDREN_yes
.byte 37 # DW_AT_producer
.byte 8 # DW_FORM_string
.byte 19 # DW_AT_language
.byte 5 # DW_FORM_data2
.byte 3 # DW_AT_name
.byte 8 # DW_FORM_string
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 3 # Abbreviation Code
.byte 57 # DW_TAG_namespace
.byte 1 # DW_CHILDREN_yes
.byte 3 # DW_AT_name
.byte 8 # DW_FORM_string
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 4 # Abbreviation Code
.byte 57 # DW_TAG_namespace
.byte 1 # DW_CHILDREN_yes
.byte 3 # DW_AT_name
.byte 8 # DW_FORM_string
.ascii "\211\001" # DW_AT_export_symbols
.byte 25 # DW_FORM_flag_present
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 5 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 0 # DW_CHILDREN_no
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 64 # DW_AT_frame_base
.byte 24 # DW_FORM_exprloc
.byte 0x47 # DW_AT_specification
.byte 0x10 # DW_FORM_ref_addr
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 6 # Abbreviation Code
.byte 36 # DW_TAG_base_type
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 8 # DW_FORM_string
.byte 62 # DW_AT_encoding
.byte 11 # DW_FORM_data1
.byte 11 # DW_AT_byte_size
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 7 # Abbreviation Code
.byte 0x3c # DW_TAG_partial_unit
.byte 1 # DW_CHILDREN_yes
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 8 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 0 # DW_CHILDREN_no
.byte 110 # DW_AT_linkage_name
.byte 8 # DW_FORM_string
.byte 3 # DW_AT_name
.byte 8 # DW_FORM_string
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 73 # DW_AT_type
.byte 0x10 # DW_FORM_ref_addr
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 9 # Abbreviation Code
.byte 0x3d # DW_TAG_imported_unit
.byte 0 # DW_CHILDREN_no
.byte 0x18 # DW_AT_import
.byte 0x10 # DW_FORM_ref_addr
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 0 # EOM(3)
.section .debug_info,"",@progbits
.Lcu_begin0:
.long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
.Ldebug_info_start0:
.short 4 # DWARF version number
.long .Labbrev0 # Offset Into Abbrev. Section
.byte 8 # Address Size (in bytes)
.byte 1 # Abbrev [1] DW_TAG_compile_unit
# DW_AT_producer
.asciz "clang version 11.0.0 (Fedora 11.0.0-2.fc33)"
.short 33 # DW_AT_language
# DW_AT_name
.asciz "-"
.quad .Lfunc_begin0 # DW_AT_low_pc
.long .Lfunc_end1-.Lfunc_begin0 # DW_AT_high_pc
.byte 9 # Abbrev [0] DW_TAG_imported_unit
.long .Lpartial_unit # DW_AT_import
.byte 3 # Abbrev [3] DW_TAG_namespace
# DW_AT_name
.asciz "N"
.byte 4 # Abbrev [4] DW_TAG_namespace
# DW_AT_name
.asciz "A"
# DW_AT_export_symbols
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.byte 5 # Abbrev [5] DW_TAG_subprogram
.quad .Lfunc_begin1 # DW_AT_low_pc
.long .Lfunc_end1-.Lfunc_begin1 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
.long .Lmethod_decl # DW_AT_specification
.Ltype_int:
.byte 6 # Abbrev [6] DW_TAG_base_type
# DW_AT_name
.asciz "int"
.byte 5 # DW_AT_encoding
.byte 4 # DW_AT_byte_size
.byte 0 # End Of Children Mark
.Ldebug_info_end0:
.Lcu_begin1:
.long .Ldebug_info_end1-.Ldebug_info_start1 # Length of Unit
.Ldebug_info_start1:
.short 4 # DWARF version number
.long .Labbrev0 # Offset Into Abbrev. Section
.byte 8 # Address Size (in bytes)
.Lpartial_unit:
.byte 7 # Abbrev [7] DW_TAG_partial_unit
.byte 3 # Abbrev [3] DW_TAG_namespace
# DW_AT_name
.asciz "N"
.byte 3 # Abbrev [3] DW_TAG_namespace
# DW_AT_name
.asciz "A"
# The Bug - missing DW_AT_export_symbols
.Lmethod_decl:
.byte 8 # Abbrev [8] DW_TAG_subprogram
# DW_AT_linkage_name
.asciz "_ZN1N1AL1mEv"
# DW_AT_name
.asciz "m"
.byte 1 # DW_AT_decl_file
.byte 1 # DW_AT_decl_line
.long .Ltype_int # DW_AT_type (DW_FORM_ref_addr)
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.Ldebug_info_end1:
.section ".note.GNU-stack","",@progbits