Add support for __debug_line_str in Mach-O

[aprantl]

Summary

This patch resolves an issue that currently accounts for the vast majority of failures on the matrix bot.

[JDevlieghere]

LGTM

[fdeazeve]

Nice and subtle fix! :)

lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp

static lldb::SectionType GetSectionType(uint32_t flags,
   static ConstString g_sect_name_objc_classlist("__objc_classlist");
   static ConstString g_sect_name_cfstring("__cfstring");
 
   static ConstString g_sect_name_dwarf_debug_abbrev("__debug_abbrev");
   static ConstString g_sect_name_dwarf_debug_aranges("__debug_aranges");
   static ConstString g_sect_name_dwarf_debug_frame("__debug_frame");
   static ConstString g_sect_name_dwarf_debug_info("__debug_info");
   static ConstString g_sect_name_dwarf_debug_line("__debug_line");
+  static ConstString g_sect_name_dwarf_debug_line_str("__debug_line_str");
   static ConstString g_sect_name_dwarf_debug_loc("__debug_loc");
   static ConstString g_sect_name_dwarf_debug_loclists("__debug_loclists");
   static ConstString g_sect_name_dwarf_debug_macinfo("__debug_macinfo");
   static ConstString g_sect_name_dwarf_debug_names("__debug_names");
   static ConstString g_sect_name_dwarf_debug_pubnames("__debug_pubnames");
   static ConstString g_sect_name_dwarf_debug_pubtypes("__debug_pubtypes");
   static ConstString g_sect_name_dwarf_debug_ranges("__debug_ranges");
   static ConstString g_sect_name_dwarf_debug_str("__debug_str");
static lldb::SectionType GetSectionType(uint32_t flags,
   if (section_name == g_sect_name_dwarf_debug_aranges)
     return eSectionTypeDWARFDebugAranges;
   if (section_name == g_sect_name_dwarf_debug_frame)
     return eSectionTypeDWARFDebugFrame;
   if (section_name == g_sect_name_dwarf_debug_info)
     return eSectionTypeDWARFDebugInfo;
   if (section_name == g_sect_name_dwarf_debug_line)
     return eSectionTypeDWARFDebugLine;
+  if (section_name == g_sect_name_dwarf_debug_line_str)
+    return eSectionTypeDWARFDebugLineStr;
   if (section_name == g_sect_name_dwarf_debug_loc)
     return eSectionTypeDWARFDebugLoc;
   if (section_name == g_sect_name_dwarf_debug_loclists)
     return eSectionTypeDWARFDebugLocLists;
   if (section_name == g_sect_name_dwarf_debug_macinfo)
     return eSectionTypeDWARFDebugMacInfo;
   if (section_name == g_sect_name_dwarf_debug_names)
     return eSectionTypeDWARFDebugNames;

lldb/test/Shell/SymbolFile/DWARF/x86/dwarf5-macho.c

+// Test that the file names in the __debug_line_str section can be decoded.
+
+// REQUIRES: system-darwin
+
+// RUN: %clang -target x86_64-apple-darwin %s -c -o %t.o -gdwarf-5
+// RUN: llvm-readobj --sections %t.o | FileCheck %s --check-prefix NAMES
+// RUN: xcrun %clang -target x86_64-apple-darwin -o %t.exe %t.o
+// RUN: %lldb %t.exe -b -o "target modules dump line-table %s" | FileCheck %s
+
+// NAMES: Name: __debug_line_str
+
+int main(int argc, char **argv) {
+  // CHECK: dwarf5-macho.c:[[@LINE+1]]
+  return 0;
+}