From Craig Silverstein: Add support for compressing .debug_str section.
[deliverable/binutils-gdb.git] / gold / layout.cc
index 4f5abac98f28aea1bd972e2c8c8616ff5bdc934d..f7c1e40be3989946d90b48e825b881a7230bd45e 100644 (file)
@@ -65,17 +65,20 @@ Layout::Layout(const General_options& options)
   : options_(options), namepool_(), sympool_(), dynpool_(), signatures_(),
     section_name_map_(), segment_list_(), section_list_(),
     unattached_section_list_(), special_output_list_(),
-    tls_segment_(NULL), symtab_section_(NULL),
+    section_headers_(NULL), tls_segment_(NULL), symtab_section_(NULL),
     dynsym_section_(NULL), dynamic_section_(NULL), dynamic_data_(NULL),
-    eh_frame_section_(NULL), output_file_size_(-1)
+    eh_frame_section_(NULL), output_file_size_(-1),
+    input_requires_executable_stack_(false),
+    input_with_gnu_stack_note_(false),
+    input_without_gnu_stack_note_(false)
 {
   // Make space for more than enough segments for a typical file.
   // This is just for efficiency--it's OK if we wind up needing more.
   this->segment_list_.reserve(12);
 
-  // We expect three unattached Output_data objects: the file header,
-  // the segment headers, and the section headers.
-  this->special_output_list_.reserve(3);
+  // We expect two unattached Output_data objects: the file header and
+  // the segment headers.
+  this->special_output_list_.reserve(2);
 }
 
 // Hash a key we use to look up an output section mapping.
@@ -94,11 +97,38 @@ is_prefix_of(const char* prefix, const char* str)
   return strncmp(prefix, str, strlen(prefix)) == 0;
 }
 
+// Returns whether the given section is in the list of
+// debug-sections-used-by-some-version-of-gdb.  Currently,
+// we've checked versions of gdb up to and including 6.7.1.
+
+static const char* gdb_sections[] =
+{ ".debug_abbrev",
+  // ".debug_aranges",   // not used by gdb as of 6.7.1
+  ".debug_frame",
+  ".debug_info",
+  ".debug_line",
+  ".debug_loc",
+  ".debug_macinfo",
+  // ".debug_pubnames",  // not used by gdb as of 6.7.1
+  ".debug_ranges",
+  ".debug_str",
+};
+
+static inline bool
+is_gdb_debug_section(const char* str)
+{
+  // We can do this faster: binary search or a hashtable.  But why bother?
+  for (size_t i = 0; i < sizeof(gdb_sections)/sizeof(*gdb_sections); ++i)
+    if (strcmp(str, gdb_sections[i]) == 0)
+      return true;
+  return false;
+}
+
 // Whether to include this section in the link.
 
 template<int size, bool big_endian>
 bool
-Layout::include_section(Object*, const char* name,
+Layout::include_section(Sized_relobj<size, big_endian>*, const char* name,
                        const elfcpp::Shdr<size, big_endian>& shdr)
 {
   // Some section types are never linked.  Some are only linked when
@@ -130,6 +160,14 @@ Layout::include_section(Object*, const char* name,
              || is_prefix_of(".stab", name))
            return false;
        }
+      if (parameters->strip_debug_gdb()
+         && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
+       {
+         // Debugging sections can only be recognized by name.
+         if (is_prefix_of(".debug", name)
+              && !is_gdb_debug_section(name))
+           return false;
+       }
       return true;
 
     default:
@@ -199,13 +237,20 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key,
 }
 
 // Return the output section to use for input section SHNDX, with name
-// NAME, with header HEADER, from object OBJECT.  Set *OFF to the
-// offset of this input section without the output section.
+// NAME, with header HEADER, from object OBJECT.  RELOC_SHNDX is the
+// index of a relocation section which applies to this section, or 0
+// if none, or -1U if more than one.  RELOC_TYPE is the type of the
+// relocation section if there is one.  Set *OFF to the offset of this
+// input section without the output section.  Return NULL if the
+// section should be discarded.  Set *OFF to -1 if the section
+// contents should not be written directly to the output file, but
+// will instead receive special handling.
 
 template<int size, bool big_endian>
 Output_section*
-Layout::layout(Relobj* object, unsigned int shndx, const char* name,
-              const elfcpp::Shdr<size, big_endian>& shdr, off_t* off)
+Layout::layout(Sized_relobj<size, big_endian>* object, unsigned int shndx,
+              const char* name, const elfcpp::Shdr<size, big_endian>& shdr,
+              unsigned int reloc_shndx, unsigned int, off_t* off)
 {
   if (!this->include_section(object, name, shdr))
     return NULL;
@@ -228,38 +273,44 @@ Layout::layout(Relobj* object, unsigned int shndx, const char* name,
                                                shdr.get_sh_type(),
                                                shdr.get_sh_flags());
 
-  // Special GNU handling of sections named .eh_frame.
-  if (!parameters->output_is_object()
-      && strcmp(name, ".eh_frame") == 0
-      && shdr.get_sh_size() > 0
-      && shdr.get_sh_type() == elfcpp::SHT_PROGBITS
-      && shdr.get_sh_flags() == elfcpp::SHF_ALLOC)
-    {
-      this->layout_eh_frame(object, shndx, name, shdr, os, off);
-      return os;
-    }
-
   // FIXME: Handle SHF_LINK_ORDER somewhere.
 
-  *off = os->add_input_section(object, shndx, name, shdr);
+  *off = os->add_input_section(object, shndx, name, shdr, reloc_shndx);
 
   return os;
 }
 
-// Special GNU handling of sections named .eh_frame.  They will
-// normally hold exception frame data.
+// Special GNU handling of sections name .eh_frame.  They will
+// normally hold exception frame data as defined by the C++ ABI
+// (http://codesourcery.com/cxx-abi/).
 
 template<int size, bool big_endian>
-void
-Layout::layout_eh_frame(Relobj* object,
+Output_section*
+Layout::layout_eh_frame(Sized_relobj<size, big_endian>* object,
+                       const unsigned char* symbols,
+                       off_t symbols_size,
+                       const unsigned char* symbol_names,
+                       off_t symbol_names_size,
                        unsigned int shndx,
-                       const char* name,
                        const elfcpp::Shdr<size, big_endian>& shdr,
-                       Output_section* os, off_t* off)
+                       unsigned int reloc_shndx, unsigned int reloc_type,
+                       off_t* off)
 {
+  gold_assert(shdr.get_sh_type() == elfcpp::SHT_PROGBITS);
+  gold_assert(shdr.get_sh_flags() == elfcpp::SHF_ALLOC);
+
+  Stringpool::Key name_key;
+  const char* name = this->namepool_.add(".eh_frame", false, &name_key);
+
+  Output_section* os = this->get_output_section(name, name_key,
+                                               elfcpp::SHT_PROGBITS,
+                                               elfcpp::SHF_ALLOC);
+
   if (this->eh_frame_section_ == NULL)
     {
       this->eh_frame_section_ = os;
+      this->eh_frame_data_ = new Eh_frame();
+      os->add_output_section_data(this->eh_frame_data_);
 
       if (this->options_.create_eh_frame_hdr())
        {
@@ -272,19 +323,39 @@ Layout::layout_eh_frame(Relobj* object,
                                     elfcpp::SHT_PROGBITS,
                                     elfcpp::SHF_ALLOC);
 
-         Eh_frame_hdr* hdr_posd = new Eh_frame_hdr(os);
+         Eh_frame_hdr* hdr_posd = new Eh_frame_hdr(os, this->eh_frame_data_);
          hdr_os->add_output_section_data(hdr_posd);
 
+         hdr_os->set_after_input_sections();
+
          Output_segment* hdr_oseg =
            new Output_segment(elfcpp::PT_GNU_EH_FRAME, elfcpp::PF_R);
          this->segment_list_.push_back(hdr_oseg);
          hdr_oseg->add_output_section(hdr_os, elfcpp::PF_R);
+
+         this->eh_frame_data_->set_eh_frame_hdr(hdr_posd);
        }
     }
 
   gold_assert(this->eh_frame_section_ == os);
 
-  *off = os->add_input_section(object, shndx, name, shdr);
+  if (this->eh_frame_data_->add_ehframe_input_section(object,
+                                                     symbols,
+                                                     symbols_size,
+                                                     symbol_names,
+                                                     symbol_names_size,
+                                                     shndx,
+                                                     reloc_shndx,
+                                                     reloc_type))
+    *off = -1;
+  else
+    {
+      // We couldn't handle this .eh_frame section for some reason.
+      // Add it as a normal section.
+      *off = os->add_input_section(object, shndx, name, shdr, reloc_shndx);
+    }
+
+  return os;
 }
 
 // Add POSD to an output section using NAME, TYPE, and FLAGS.
@@ -322,7 +393,7 @@ Output_section*
 Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
                            elfcpp::Elf_Xword flags)
 {
-  Output_section* os = new Output_section(name, type, flags);
+  Output_section* os = new Output_section(this->options_, name, type, flags);
   this->section_list_.push_back(os);
 
   if ((flags & elfcpp::SHF_ALLOC) == 0)
@@ -404,6 +475,27 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
   return os;
 }
 
+// Handle the .note.GNU-stack section at layout time.  SEEN_GNU_STACK
+// is whether we saw a .note.GNU-stack section in the object file.
+// GNU_STACK_FLAGS is the section flags.  The flags give the
+// protection required for stack memory.  We record this in an
+// executable as a PT_GNU_STACK segment.  If an object file does not
+// have a .note.GNU-stack segment, we must assume that it is an old
+// object.  On some targets that will force an executable stack.
+
+void
+Layout::layout_gnu_stack(bool seen_gnu_stack, uint64_t gnu_stack_flags)
+{
+  if (!seen_gnu_stack)
+    this->input_without_gnu_stack_note_ = true;
+  else
+    {
+      this->input_with_gnu_stack_note_ = true;
+      if ((gnu_stack_flags & elfcpp::SHF_EXECINSTR) != 0)
+       this->input_requires_executable_stack_ = true;
+    }
+}
+
 // Create the dynamic sections which are needed before we read the
 // relocs.
 
@@ -411,7 +503,7 @@ void
 Layout::create_initial_dynamic_sections(const Input_objects* input_objects,
                                        Symbol_table* symtab)
 {
-  if (!input_objects->any_dynamic())
+  if (parameters->doing_static_link())
     return;
 
   const char* dynamic_name = this->namepool_.add(".dynamic", false, NULL);
@@ -542,10 +634,11 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
 
   target->finalize_sections(this);
 
-  this->create_note_section();
+  this->create_gold_note();
+  this->create_executable_stack_info(target);
 
   Output_segment* phdr_seg = NULL;
-  if (input_objects->any_dynamic())
+  if (!parameters->doing_static_link())
     {
       // There was a dynamic object in the link.  We need to create
       // some information for the dynamic linker.
@@ -566,7 +659,8 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
 
       // Create the .interp section to hold the name of the
       // interpreter, and put it in a PT_INTERP segment.
-      this->create_interp(target);
+      if (!parameters->output_is_shared())
+        this->create_interp(target);
 
       // Finish the .dynamic section to hold the dynamic data, and put
       // it in a PT_DYNAMIC segment.
@@ -578,7 +672,7 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
 
       // Create the version sections.  We can't do this until the
       // dynamic string table is complete.
-      this->create_version_sections(&versions, local_dynamic_count,
+      this->create_version_sections(&versions, symtab, local_dynamic_count,
                                    dynamic_symbols, dynstr);
     }
 
@@ -601,7 +695,7 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
   this->special_output_list_.push_back(file_header);
 
   // We set the output section indexes in set_segment_offsets and
-  // set_section_offsets.
+  // set_section_indexes.
   unsigned int shndx = 1;
 
   // Set the file offsets of all the segments, and all the sections
@@ -614,16 +708,20 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
   // Create the .shstrtab section.
   Output_section* shstrtab_section = this->create_shstrtab();
 
-  // Set the file offsets of all the sections not associated with
-  // segments.
-  off = this->set_section_offsets(off, &shndx);
+  // Set the file offsets of all the non-data sections which don't
+  // have to wait for the input sections.
+  off = this->set_section_offsets(off, BEFORE_INPUT_SECTIONS_PASS);
+
+  // Now that all sections have been created, set the section indexes.
+  shndx = this->set_section_indexes(shndx);
 
   // Create the section table header.
-  Output_section_headers* oshdrs = this->create_shdrs(&off);
+  this->create_shdrs(&off);
 
-  file_header->set_section_info(oshdrs, shstrtab_section);
+  file_header->set_section_info(this->section_headers_, shstrtab_section);
 
-  // Now we know exactly where everything goes in the output file.
+  // Now we know exactly where everything goes in the output file
+  // (except for non-allocated sections which require postprocessing).
   Output_data::layout_complete();
 
   this->output_file_size_ = off;
@@ -635,7 +733,7 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
 // records the version of gold used to create the binary.
 
 void
-Layout::create_note_section()
+Layout::create_gold_note()
 {
   if (parameters->output_is_object())
     return;
@@ -651,7 +749,7 @@ Layout::create_note_section()
   // version 2.16.91), and glibc always generates the latter for
   // .note.ABI-tag (as of version 1.6), so that's the one we go with
   // here.
-#ifdef GABI_FORMAT_FOR_DOTNOTE_SECTION   // this is not defined by default
+#ifdef GABI_FORMAT_FOR_DOTNOTE_SECTION   // This is not defined by default.
   const int size = parameters->get_size();
 #else
   const int size = 32;
@@ -719,6 +817,54 @@ Layout::create_note_section()
   os->add_output_section_data(posd);
 }
 
+// Record whether the stack should be executable.  This can be set
+// from the command line using the -z execstack or -z noexecstack
+// options.  Otherwise, if any input file has a .note.GNU-stack
+// section with the SHF_EXECINSTR flag set, the stack should be
+// executable.  Otherwise, if at least one input file a
+// .note.GNU-stack section, and some input file has no .note.GNU-stack
+// section, we use the target default for whether the stack should be
+// executable.  Otherwise, we don't generate a stack note.  When
+// generating a object file, we create a .note.GNU-stack section with
+// the appropriate marking.  When generating an executable or shared
+// library, we create a PT_GNU_STACK segment.
+
+void
+Layout::create_executable_stack_info(const Target* target)
+{
+  bool is_stack_executable;
+  if (this->options_.is_execstack_set())
+    is_stack_executable = this->options_.is_stack_executable();
+  else if (!this->input_with_gnu_stack_note_)
+    return;
+  else
+    {
+      if (this->input_requires_executable_stack_)
+       is_stack_executable = true;
+      else if (this->input_without_gnu_stack_note_)
+       is_stack_executable = target->is_default_stack_executable();
+      else
+       is_stack_executable = false;
+    }
+
+  if (parameters->output_is_object())
+    {
+      const char* name = this->namepool_.add(".note.GNU-stack", false, NULL);
+      elfcpp::Elf_Xword flags = 0;
+      if (is_stack_executable)
+       flags |= elfcpp::SHF_EXECINSTR;
+      this->make_output_section(name, elfcpp::SHT_PROGBITS, flags);
+    }
+  else
+    {
+      int flags = elfcpp::PF_R | elfcpp::PF_W;
+      if (is_stack_executable)
+       flags |= elfcpp::PF_X;
+      Output_segment* oseg = new Output_segment(elfcpp::PT_GNU_STACK, flags);
+      this->segment_list_.push_back(oseg);
+    }
+}
+
 // Return whether SEG1 should be before SEG2 in the output file.  This
 // is based entirely on the segment type and flags.  When this is
 // called the segment addresses has normally not yet been set.
@@ -913,23 +1059,65 @@ Layout::set_segment_offsets(const Target* target, Output_segment* load_seg,
 // segment.
 
 off_t
-Layout::set_section_offsets(off_t off, unsigned int* pshndx)
+Layout::set_section_offsets(off_t off, Layout::Section_offset_pass pass)
 {
   for (Section_list::iterator p = this->unattached_section_list_.begin();
        p != this->unattached_section_list_.end();
        ++p)
     {
-      (*p)->set_out_shndx(*pshndx);
-      ++*pshndx;
-      if ((*p)->offset() != -1)
+      // The symtab section is handled in create_symtab_sections.
+      if (*p == this->symtab_section_)
        continue;
+
+      if (pass == BEFORE_INPUT_SECTIONS_PASS
+          && (*p)->after_input_sections())
+        continue;
+      else if (pass == AFTER_INPUT_SECTIONS_PASS
+               && (!(*p)->after_input_sections()
+                   || (*p)->type() == elfcpp::SHT_STRTAB))
+        continue;
+      else if (pass == STRTAB_AFTER_INPUT_SECTIONS_PASS
+               && (!(*p)->after_input_sections()
+                   || (*p)->type() != elfcpp::SHT_STRTAB))
+        continue;
+
       off = align_address(off, (*p)->addralign());
-      (*p)->set_address(0, off);
+      (*p)->set_file_offset(off);
+      (*p)->finalize_data_size();
       off += (*p)->data_size();
     }
   return off;
 }
 
+// Allow any section not associated with a segment to change its
+// output section name at the last minute.
+
+void
+Layout::modify_section_names()
+{
+  for (Section_list::iterator p = this->unattached_section_list_.begin();
+       p != this->unattached_section_list_.end();
+       ++p)
+    if ((*p)->maybe_modify_output_section_name())
+      this->namepool_.add((*p)->name(), true, NULL);
+}
+
+// Set the section indexes of all the sections not associated with a
+// segment.
+
+unsigned int
+Layout::set_section_indexes(unsigned int shndx)
+{
+  for (Section_list::iterator p = this->unattached_section_list_.begin();
+       p != this->unattached_section_list_.end();
+       ++p)
+    {
+      (*p)->set_out_shndx(shndx);
+      ++shndx;
+    }
+  return shndx;
+}
+
 // Create the symbol table sections.  Here we also set the final
 // values of the symbols.  At this point all the loadable sections are
 // fully laid out.
@@ -1025,8 +1213,8 @@ Layout::create_symtab_sections(const Input_objects* input_objects,
                                                          0);
       this->symtab_section_ = osymtab;
 
-      Output_section_data* pos = new Output_data_space(off - startoff,
-                                                      align);
+      Output_section_data* pos = new Output_data_fixed_space(off - startoff,
+                                                            align);
       osymtab->add_output_section_data(pos);
 
       const char* strtab_name = this->namepool_.add(".strtab", false, NULL);
@@ -1037,7 +1225,8 @@ Layout::create_symtab_sections(const Input_objects* input_objects,
       Output_section_data* pstr = new Output_data_strtab(&this->sympool_);
       ostrtab->add_output_section_data(pstr);
 
-      osymtab->set_address(0, startoff);
+      osymtab->set_file_offset(startoff);
+      osymtab->finalize_data_size();
       osymtab->set_link_section(ostrtab);
       osymtab->set_info(local_symcount);
       osymtab->set_entsize(symsize);
@@ -1058,10 +1247,13 @@ Layout::create_shstrtab()
 
   const char* name = this->namepool_.add(".shstrtab", false, NULL);
 
-  this->namepool_.set_string_offsets();
-
   Output_section* os = this->make_output_section(name, elfcpp::SHT_STRTAB, 0);
 
+  // We can't write out this section until we've set all the section
+  // names, and we don't set the names of compressed output sections
+  // until relocations are complete.
+  os->set_after_input_sections();
+
   Output_section_data* posd = new Output_data_strtab(&this->namepool_);
   os->add_output_section_data(posd);
 
@@ -1071,7 +1263,7 @@ Layout::create_shstrtab()
 // Create the section headers.  SIZE is 32 or 64.  OFF is the file
 // offset.
 
-Output_section_headers*
+void
 Layout::create_shdrs(off_t* poff)
 {
   Output_section_headers* oshdrs;
@@ -1080,11 +1272,10 @@ Layout::create_shdrs(off_t* poff)
                                      &this->unattached_section_list_,
                                      &this->namepool_);
   off_t off = align_address(*poff, oshdrs->addralign());
-  oshdrs->set_address(0, off);
+  oshdrs->set_address_and_file_offset(0, off);
   off += oshdrs->data_size();
   *poff = off;
-  this->special_output_list_.push_back(oshdrs);
-  return oshdrs;
+  this->section_headers_ = oshdrs;
 }
 
 // Create the dynamic symbol table.
@@ -1126,9 +1317,8 @@ Layout::create_dynamic_symtab(const Target* target, Symbol_table* symtab,
 
   // FIXME: We have to tell set_dynsym_indexes whether the
   // -E/--export-dynamic option was used.
-  index = symtab->set_dynsym_indexes(&this->options_, target, index,
-                                    pdynamic_symbols, &this->dynpool_,
-                                    pversions);
+  index = symtab->set_dynsym_indexes(target, index, pdynamic_symbols,
+                                    &this->dynpool_, pversions);
 
   int symsize;
   unsigned int align;
@@ -1153,8 +1343,8 @@ Layout::create_dynamic_symtab(const Target* target, Symbol_table* symtab,
                                                     elfcpp::SHT_DYNSYM,
                                                     elfcpp::SHF_ALLOC);
 
-  Output_section_data* odata = new Output_data_space(index * symsize,
-                                                    align);
+  Output_section_data* odata = new Output_data_fixed_space(index * symsize,
+                                                          align);
   dynsym->add_output_section_data(odata);
 
   dynsym->set_info(local_symcount);
@@ -1214,6 +1404,7 @@ Layout::create_dynamic_symtab(const Target* target, Symbol_table* symtab,
 
 void
 Layout::create_version_sections(const Versions* versions,
+                               const Symbol_table* symtab,
                                unsigned int local_symcount,
                                const std::vector<Symbol*>& dynamic_symbols,
                                const Output_section* dynstr)
@@ -1228,7 +1419,7 @@ Layout::create_version_sections(const Versions* versions,
 #ifdef HAVE_TARGET_32_BIG
           this->sized_create_version_sections
               SELECT_SIZE_ENDIAN_NAME(32, true)(
-                  versions, local_symcount, dynamic_symbols, dynstr
+                 versions, symtab, local_symcount, dynamic_symbols, dynstr
                   SELECT_SIZE_ENDIAN(32, true));
 #else
           gold_unreachable();
@@ -1239,7 +1430,7 @@ Layout::create_version_sections(const Versions* versions,
 #ifdef HAVE_TARGET_32_LITTLE
           this->sized_create_version_sections
               SELECT_SIZE_ENDIAN_NAME(32, false)(
-                  versions, local_symcount, dynamic_symbols, dynstr
+                 versions, symtab, local_symcount, dynamic_symbols, dynstr
                   SELECT_SIZE_ENDIAN(32, false));
 #else
           gold_unreachable();
@@ -1253,7 +1444,7 @@ Layout::create_version_sections(const Versions* versions,
 #ifdef HAVE_TARGET_64_BIG
           this->sized_create_version_sections
               SELECT_SIZE_ENDIAN_NAME(64, true)(
-                  versions, local_symcount, dynamic_symbols, dynstr
+                  versions, symtab, local_symcount, dynamic_symbols, dynstr
                   SELECT_SIZE_ENDIAN(64, true));
 #else
           gold_unreachable();
@@ -1264,7 +1455,7 @@ Layout::create_version_sections(const Versions* versions,
 #ifdef HAVE_TARGET_64_LITTLE
           this->sized_create_version_sections
               SELECT_SIZE_ENDIAN_NAME(64, false)(
-                  versions, local_symcount, dynamic_symbols, dynstr
+                  versions, symtab, local_symcount, dynamic_symbols, dynstr
                   SELECT_SIZE_ENDIAN(64, false));
 #else
           gold_unreachable();
@@ -1281,6 +1472,7 @@ template<int size, bool big_endian>
 void
 Layout::sized_create_version_sections(
     const Versions* versions,
+    const Symbol_table* symtab,
     unsigned int local_symcount,
     const std::vector<Symbol*>& dynamic_symbols,
     const Output_section* dynstr
@@ -1294,7 +1486,7 @@ Layout::sized_create_version_sections(
   unsigned char* vbuf;
   unsigned int vsize;
   versions->symbol_section_contents SELECT_SIZE_ENDIAN_NAME(size, big_endian)(
-      &this->dynpool_, local_symcount, dynamic_symbols, &vbuf, &vsize
+      symtab, &this->dynpool_, local_symcount, dynamic_symbols, &vbuf, &vsize
       SELECT_SIZE_ENDIAN(size, big_endian));
 
   Output_section_data* vdata = new Output_data_const_buffer(vbuf, vsize, 2);
@@ -1447,6 +1639,27 @@ Layout::finish_dynamic_section(const Input_objects* input_objects,
 
       odyn->add_string(elfcpp::DT_RPATH, rpath_val);
     }
+
+  // Look for text segments that have dynamic relocations.
+  bool have_textrel = false;
+  for (Segment_list::const_iterator p = this->segment_list_.begin();
+       p != this->segment_list_.end();
+       ++p)
+    {
+      if (((*p)->flags() & elfcpp::PF_W) == 0
+         && (*p)->dynamic_reloc_count() > 0)
+       {
+         have_textrel = true;
+         break;
+       }
+    }
+
+  // Add a DT_FLAGS entry. We add it even if no flags are set so that
+  // post-link tools can easily modify these flags if desired.
+  unsigned int flags = 0;
+  if (have_textrel)
+    flags |= elfcpp::DF_TEXTREL;
+  odyn->add_constant(elfcpp::DT_FLAGS, flags);
 }
 
 // The mapping of .gnu.linkonce section names to real section names.
@@ -1514,41 +1727,68 @@ Layout::output_section_name(const char* name, size_t* plen)
       return Layout::linkonce_output_name(name, plen);
     }
 
-  // If the section name has no '.', or only an initial '.', we use
-  // the name unchanged (i.e., ".text" is unchanged).
-
-  // Otherwise, if the section name does not include ".rel", we drop
-  // the last '.'  and everything that follows (i.e., ".text.XXX"
-  // becomes ".text").
-
-  // Otherwise, if the section name has zero or one '.' after the
-  // ".rel", we use the name unchanged (i.e., ".rel.text" is
-  // unchanged).
-
-  // Otherwise, we drop the last '.' and everything that follows
-  // (i.e., ".rel.text.XXX" becomes ".rel.text").
+  // gcc 4.3 generates the following sorts of section names when it
+  // needs a section name specific to a function:
+  //   .text.FN
+  //   .rodata.FN
+  //   .sdata2.FN
+  //   .data.FN
+  //   .data.rel.FN
+  //   .data.rel.local.FN
+  //   .data.rel.ro.FN
+  //   .data.rel.ro.local.FN
+  //   .sdata.FN
+  //   .bss.FN
+  //   .sbss.FN
+  //   .tdata.FN
+  //   .tbss.FN
+
+  // The GNU linker maps all of those to the part before the .FN,
+  // except that .data.rel.local.FN is mapped to .data, and
+  // .data.rel.ro.local.FN is mapped to .data.rel.ro.  The sections
+  // beginning with .data.rel.ro.local are grouped together.
+
+  // For an anonymous namespace, the string FN can contain a '.'.
+
+  // Also of interest: .rodata.strN.N, .rodata.cstN, both of which the
+  // GNU linker maps to .rodata.
+
+  // The .data.rel.ro sections enable a security feature triggered by
+  // the -z relro option.  Section which need to be relocated at
+  // program startup time but which may be readonly after startup are
+  // grouped into .data.rel.ro.  They are then put into a PT_GNU_RELRO
+  // segment.  The dynamic linker will make that segment writable,
+  // perform relocations, and then make it read-only.  FIXME: We do
+  // not yet implement this optimization.
+
+  // It is hard to handle this in a principled way.
+
+  // These are the rules we follow:
+
+  // If the section name has no initial '.', or no dot other than an
+  // initial '.', we use the name unchanged (i.e., "mysection" and
+  // ".text" are unchanged).
+
+  // If the name starts with ".data.rel.ro" we use ".data.rel.ro".
+
+  // Otherwise, we drop the second '.' and everything that comes after
+  // it (i.e., ".text.XXX" becomes ".text").
 
   const char* s = name;
-  if (*s == '.')
-    ++s;
+  if (*s != '.')
+    return name;
+  ++s;
   const char* sdot = strchr(s, '.');
   if (sdot == NULL)
     return name;
 
-  const char* srel = strstr(s, ".rel");
-  if (srel == NULL)
+  const char* const data_rel_ro = ".data.rel.ro";
+  if (strncmp(name, data_rel_ro, strlen(data_rel_ro)) == 0)
     {
-      *plen = sdot - name;
-      return name;
+      *plen = strlen(data_rel_ro);
+      return data_rel_ro;
     }
 
-  sdot = strchr(srel + 1, '.');
-  if (sdot == NULL)
-    return name;
-  sdot = strchr(sdot + 1, '.');
-  if (sdot == NULL)
-    return name;
-
   *plen = sdot - name;
   return name;
 }
@@ -1595,6 +1835,22 @@ Layout::add_comdat(const char* signature, bool group)
     }
 }
 
+// Write out the Output_sections.  Most won't have anything to write,
+// since most of the data will come from input sections which are
+// handled elsewhere.  But some Output_sections do have Output_data.
+
+void
+Layout::write_output_sections(Output_file* of) const
+{
+  for (Section_list::const_iterator p = this->section_list_.begin();
+       p != this->section_list_.end();
+       ++p)
+    {
+      if (!(*p)->after_input_sections())
+       (*p)->write(of);
+    }
+}
+
 // Write out data not associated with a section or the symbol table.
 
 void
@@ -1635,15 +1891,6 @@ Layout::write_data(const Symbol_table* symtab, Output_file* of) const
        }
     }
 
-  // Write out the Output_sections.  Most won't have anything to
-  // write, since most of the data will come from input sections which
-  // are handled elsewhere.  But some Output_sections do have
-  // Output_data.
-  for (Section_list::const_iterator p = this->section_list_.begin();
-       p != this->section_list_.end();
-       ++p)
-    (*p)->write(of);
-
   // Write out the Output_data which are not in an Output_section.
   for (Data_list::const_iterator p = this->special_output_list_.begin();
        p != this->special_output_list_.end();
@@ -1651,6 +1898,95 @@ Layout::write_data(const Symbol_table* symtab, Output_file* of) const
     (*p)->write(of);
 }
 
+// Write out the Output_sections which can only be written after the
+// input sections are complete.
+
+void
+Layout::write_sections_after_input_sections(Output_file* of)
+{
+  // Determine the final section offsets, and thus the final output
+  // file size.  Note we finalize the .shstrab last, to allow the
+  // after_input_section sections to modify their section-names before
+  // writing.
+  off_t off = this->output_file_size_;
+  off = this->set_section_offsets(off, AFTER_INPUT_SECTIONS_PASS);
+
+  // Determine the final section names as well (at least, for sections
+  // that we haven't written yet).
+  this->modify_section_names();
+
+  // Now that we've finalized the names, we can finalize the shstrab.
+  off = this->set_section_offsets(off, STRTAB_AFTER_INPUT_SECTIONS_PASS);
+
+  if (off > this->output_file_size_)
+    {
+      of->resize(off);
+      this->output_file_size_ = off;
+    }
+
+  for (Section_list::const_iterator p = this->section_list_.begin();
+       p != this->section_list_.end();
+       ++p)
+    {
+      if ((*p)->after_input_sections())
+       (*p)->write(of);
+    }
+
+  for (Section_list::const_iterator p = this->unattached_section_list_.begin();
+       p != this->unattached_section_list_.end();
+       ++p)
+    {
+      if ((*p)->after_input_sections())
+       (*p)->write(of);
+    }
+
+  this->section_headers_->write(of);
+}
+
+// Write_sections_task methods.
+
+// We can always run this task.
+
+Task::Is_runnable_type
+Write_sections_task::is_runnable(Workqueue*)
+{
+  return IS_RUNNABLE;
+}
+
+// We need to unlock both OUTPUT_SECTIONS_BLOCKER and FINAL_BLOCKER
+// when finished.
+
+class Write_sections_task::Write_sections_locker : public Task_locker
+{
+ public:
+  Write_sections_locker(Task_token& output_sections_blocker,
+                       Task_token& final_blocker,
+                       Workqueue* workqueue)
+    : output_sections_block_(output_sections_blocker, workqueue),
+      final_block_(final_blocker, workqueue)
+  { }
+
+ private:
+  Task_block_token output_sections_block_;
+  Task_block_token final_block_;
+};
+
+Task_locker*
+Write_sections_task::locks(Workqueue* workqueue)
+{
+  return new Write_sections_locker(*this->output_sections_blocker_,
+                                  *this->final_blocker_,
+                                  workqueue);
+}
+
+// Run the task--write out the data.
+
+void
+Write_sections_task::run(Workqueue*)
+{
+  this->layout_->write_output_sections(this->of_);
+}
+
 // Write_data_task methods.
 
 // We can always run this task.
@@ -1700,8 +2036,36 @@ Write_symbols_task::locks(Workqueue* workqueue)
 void
 Write_symbols_task::run(Workqueue*)
 {
-  this->symtab_->write_globals(this->target_, this->sympool_, this->dynpool_,
-                              this->of_);
+  this->symtab_->write_globals(this->input_objects_, this->sympool_,
+                              this->dynpool_, this->of_);
+}
+
+// Write_after_input_sections_task methods.
+
+// We can only run this task after the input sections have completed.
+
+Task::Is_runnable_type
+Write_after_input_sections_task::is_runnable(Workqueue*)
+{
+  if (this->input_sections_blocker_->is_blocked())
+    return IS_BLOCKED;
+  return IS_RUNNABLE;
+}
+
+// We need to unlock FINAL_BLOCKER when finished.
+
+Task_locker*
+Write_after_input_sections_task::locks(Workqueue* workqueue)
+{
+  return new Task_locker_block(*this->final_blocker_, workqueue);
+}
+
+// Run the task.
+
+void
+Write_after_input_sections_task::run(Workqueue*)
+{
+  this->layout_->write_sections_after_input_sections(this->of_);
 }
 
 // Close_task_runner methods.
@@ -1720,30 +2084,97 @@ Close_task_runner::run(Workqueue*)
 #ifdef HAVE_TARGET_32_LITTLE
 template
 Output_section*
-Layout::layout<32, false>(Relobj* object, unsigned int shndx, const char* name,
-                         const elfcpp::Shdr<32, false>& shdr, off_t*);
+Layout::layout<32, false>(Sized_relobj<32, false>* object, unsigned int shndx,
+                         const char* name,
+                         const elfcpp::Shdr<32, false>& shdr,
+                         unsigned int, unsigned int, off_t*);
 #endif
 
 #ifdef HAVE_TARGET_32_BIG
 template
 Output_section*
-Layout::layout<32, true>(Relobj* object, unsigned int shndx, const char* name,
-                        const elfcpp::Shdr<32, true>& shdr, off_t*);
+Layout::layout<32, true>(Sized_relobj<32, true>* object, unsigned int shndx,
+                        const char* name,
+                        const elfcpp::Shdr<32, true>& shdr,
+                        unsigned int, unsigned int, off_t*);
 #endif
 
 #ifdef HAVE_TARGET_64_LITTLE
 template
 Output_section*
-Layout::layout<64, false>(Relobj* object, unsigned int shndx, const char* name,
-                         const elfcpp::Shdr<64, false>& shdr, off_t*);
+Layout::layout<64, false>(Sized_relobj<64, false>* object, unsigned int shndx,
+                         const char* name,
+                         const elfcpp::Shdr<64, false>& shdr,
+                         unsigned int, unsigned int, off_t*);
 #endif
 
 #ifdef HAVE_TARGET_64_BIG
 template
 Output_section*
-Layout::layout<64, true>(Relobj* object, unsigned int shndx, const char* name,
-                        const elfcpp::Shdr<64, true>& shdr, off_t*);
+Layout::layout<64, true>(Sized_relobj<64, true>* object, unsigned int shndx,
+                        const char* name,
+                        const elfcpp::Shdr<64, true>& shdr,
+                        unsigned int, unsigned int, off_t*);
+#endif
+
+#ifdef HAVE_TARGET_32_LITTLE
+template
+Output_section*
+Layout::layout_eh_frame<32, false>(Sized_relobj<32, false>* object,
+                                  const unsigned char* symbols,
+                                  off_t symbols_size,
+                                  const unsigned char* symbol_names,
+                                  off_t symbol_names_size,
+                                  unsigned int shndx,
+                                  const elfcpp::Shdr<32, false>& shdr,
+                                  unsigned int reloc_shndx,
+                                  unsigned int reloc_type,
+                                  off_t* off);
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+Output_section*
+Layout::layout_eh_frame<32, true>(Sized_relobj<32, true>* object,
+                                  const unsigned char* symbols,
+                                  off_t symbols_size,
+                                 const unsigned char* symbol_names,
+                                 off_t symbol_names_size,
+                                 unsigned int shndx,
+                                 const elfcpp::Shdr<32, true>& shdr,
+                                 unsigned int reloc_shndx,
+                                 unsigned int reloc_type,
+                                 off_t* off);
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+Output_section*
+Layout::layout_eh_frame<64, false>(Sized_relobj<64, false>* object,
+                                  const unsigned char* symbols,
+                                  off_t symbols_size,
+                                  const unsigned char* symbol_names,
+                                  off_t symbol_names_size,
+                                  unsigned int shndx,
+                                  const elfcpp::Shdr<64, false>& shdr,
+                                  unsigned int reloc_shndx,
+                                  unsigned int reloc_type,
+                                  off_t* off);
 #endif
 
+#ifdef HAVE_TARGET_64_BIG
+template
+Output_section*
+Layout::layout_eh_frame<64, true>(Sized_relobj<64, true>* object,
+                                  const unsigned char* symbols,
+                                  off_t symbols_size,
+                                 const unsigned char* symbol_names,
+                                 off_t symbol_names_size,
+                                 unsigned int shndx,
+                                 const elfcpp::Shdr<64, true>& shdr,
+                                 unsigned int reloc_shndx,
+                                 unsigned int reloc_type,
+                                 off_t* off);
+#endif
 
 } // End namespace gold.
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