resized_signatures_(false),
have_stabstr_section_(false),
section_ordering_specified_(false),
+ unique_segment_for_sections_specified_(false),
incremental_inputs_(NULL),
record_output_section_data_from_script_(false),
script_output_section_data_list_(),
segment_states_(NULL),
relaxation_debug_check_(NULL),
section_order_map_(),
+ section_segment_map_(),
input_section_position_(),
input_section_glob_(),
incremental_base_(NULL),
return k.first + k.second.first + k.second.second;
}
-// 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.
+// These are the debug sections that are actually used by gdb.
+// Currently, we've checked versions of gdb up to and including 7.4.
+// We only check the part of the name that follows ".debug_" or
+// ".zdebug_".
static const char* gdb_sections[] =
-{ ".debug_abbrev",
- // ".debug_aranges", // not used by gdb as of 6.7.1
- ".debug_frame",
- ".debug_info",
- ".debug_types",
- ".debug_line",
- ".debug_loc",
- ".debug_macinfo",
- // ".debug_pubnames", // not used by gdb as of 6.7.1
- ".debug_ranges",
- ".debug_str",
+{
+ "abbrev",
+ "addr", // Fission extension
+ // "aranges", // not used by gdb as of 7.4
+ "frame",
+ "info",
+ "types",
+ "line",
+ "loc",
+ "macinfo",
+ "macro",
+ // "pubnames", // not used by gdb as of 7.4
+ // "pubtypes", // not used by gdb as of 7.4
+ "ranges",
+ "str",
};
+// This is the minimum set of sections needed for line numbers.
+
static const char* lines_only_debug_sections[] =
-{ ".debug_abbrev",
- // ".debug_aranges", // not used by gdb as of 6.7.1
- // ".debug_frame",
- ".debug_info",
- // ".debug_types",
- ".debug_line",
- // ".debug_loc",
- // ".debug_macinfo",
- // ".debug_pubnames", // not used by gdb as of 6.7.1
- // ".debug_ranges",
- ".debug_str",
+{
+ "abbrev",
+ // "addr", // Fission extension
+ // "aranges", // not used by gdb as of 7.4
+ // "frame",
+ "info",
+ // "types",
+ "line",
+ // "loc",
+ // "macinfo",
+ // "macro",
+ // "pubnames", // not used by gdb as of 7.4
+ // "pubtypes", // not used by gdb as of 7.4
+ // "ranges",
+ "str",
+};
+
+// These sections are the DWARF fast-lookup tables, and are not needed
+// when building a .gdb_index section.
+
+static const char* gdb_fast_lookup_sections[] =
+{
+ "aranges",
+ "pubnames",
+ "pubtypes",
};
+// Returns whether the given debug section is in the list of
+// debug-sections-used-by-some-version-of-gdb. SUFFIX is the
+// portion of the name following ".debug_" or ".zdebug_".
+
static inline bool
-is_gdb_debug_section(const char* str)
+is_gdb_debug_section(const char* suffix)
{
// 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)
+ if (strcmp(suffix, gdb_sections[i]) == 0)
return true;
return false;
}
+// Returns whether the given section is needed for lines-only debugging.
+
static inline bool
-is_lines_only_debug_section(const char* str)
+is_lines_only_debug_section(const char* suffix)
{
// We can do this faster: binary search or a hashtable. But why bother?
for (size_t i = 0;
i < sizeof(lines_only_debug_sections)/sizeof(*lines_only_debug_sections);
++i)
- if (strcmp(str, lines_only_debug_sections[i]) == 0)
+ if (strcmp(suffix, lines_only_debug_sections[i]) == 0)
+ return true;
+ return false;
+}
+
+// Returns whether the given section is a fast-lookup section that
+// will not be needed when building a .gdb_index section.
+
+static inline bool
+is_gdb_fast_lookup_section(const char* suffix)
+{
+ // We can do this faster: binary search or a hashtable. But why bother?
+ for (size_t i = 0;
+ i < sizeof(gdb_fast_lookup_sections)/sizeof(*gdb_fast_lookup_sections);
+ ++i)
+ if (strcmp(suffix, gdb_fast_lookup_sections[i]) == 0)
return true;
return false;
}
case elfcpp::SHT_GROUP:
// If we are emitting relocations these should be handled
// elsewhere.
- gold_assert(!parameters->options().relocatable()
- && !parameters->options().emit_relocs());
+ gold_assert(!parameters->options().relocatable());
return false;
case elfcpp::SHT_PROGBITS:
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
{
// Debugging sections can only be recognized by name.
- if (is_prefix_of(".debug", name)
- && !is_lines_only_debug_section(name))
+ if (is_prefix_of(".debug_", name)
+ && !is_lines_only_debug_section(name + 7))
+ return false;
+ if (is_prefix_of(".zdebug_", name)
+ && !is_lines_only_debug_section(name + 8))
return false;
}
if (parameters->options().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))
+ if (is_prefix_of(".debug_", name)
+ && !is_gdb_debug_section(name + 7))
+ return false;
+ if (is_prefix_of(".zdebug_", name)
+ && !is_gdb_debug_section(name + 8))
+ return false;
+ }
+ if (parameters->options().gdb_index()
+ && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
+ {
+ // When building .gdb_index, we can strip .debug_pubnames,
+ // .debug_pubtypes, and .debug_aranges sections.
+ if (is_prefix_of(".debug_", name)
+ && is_gdb_fast_lookup_section(name + 7))
+ return false;
+ if (is_prefix_of(".zdebug_", name)
+ && is_gdb_fast_lookup_section(name + 8))
return false;
}
if (parameters->options().strip_lto_sections()
}
}
+// Returns TRUE iff NAME (an input section from RELOBJ) will
+// be mapped to an output section that should be KEPT.
+
+bool
+Layout::keep_input_section(const Relobj* relobj, const char* name)
+{
+ if (! this->script_options_->saw_sections_clause())
+ return false;
+
+ Script_sections* ss = this->script_options_->script_sections();
+ const char* file_name = relobj == NULL ? NULL : relobj->name().c_str();
+ Output_section** output_section_slot;
+ Script_sections::Section_type script_section_type;
+ bool keep;
+
+ name = ss->output_section_name(file_name, name, &output_section_slot,
+ &script_section_type, &keep);
+ return name != NULL && keep;
+}
+
+// Clear the input section flags that should not be copied to the
+// output section.
+
+elfcpp::Elf_Xword
+Layout::get_output_section_flags(elfcpp::Elf_Xword input_section_flags)
+{
+ // Some flags in the input section should not be automatically
+ // copied to the output section.
+ input_section_flags &= ~ (elfcpp::SHF_INFO_LINK
+ | elfcpp::SHF_GROUP
+ | elfcpp::SHF_MERGE
+ | elfcpp::SHF_STRINGS);
+
+ // We only clear the SHF_LINK_ORDER flag in for
+ // a non-relocatable link.
+ if (!parameters->options().relocatable())
+ input_section_flags &= ~elfcpp::SHF_LINK_ORDER;
+
+ return input_section_flags;
+}
+
// Pick the output section to use for section NAME, in input file
// RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
// linker created section. IS_INPUT_SECTION is true if we are
// sections to segments.
gold_assert(!is_input_section || !this->sections_are_attached_);
- // Some flags in the input section should not be automatically
- // copied to the output section.
- flags &= ~ (elfcpp::SHF_INFO_LINK
- | elfcpp::SHF_GROUP
- | elfcpp::SHF_MERGE
- | elfcpp::SHF_STRINGS);
-
- // We only clear the SHF_LINK_ORDER flag in for
- // a non-relocatable link.
- if (!parameters->options().relocatable())
- flags &= ~elfcpp::SHF_LINK_ORDER;
+ flags = this->get_output_section_flags(flags);
if (this->script_options_->saw_sections_clause())
{
Output_section** output_section_slot;
Script_sections::Section_type script_section_type;
const char* orig_name = name;
+ bool keep;
name = ss->output_section_name(file_name, name, &output_section_slot,
- &script_section_type);
+ &script_section_type, &keep);
+
if (name == NULL)
{
gold_debug(DEBUG_SCRIPT, _("Unable to create output section '%s' "
if (is_input_section
&& !this->script_options_->saw_sections_clause()
&& !parameters->options().relocatable())
- name = Layout::output_section_name(relobj, name, &len);
+ {
+ const char *orig_name = name;
+ name = parameters->target().output_section_name(relobj, name, &len);
+ if (name == NULL)
+ name = Layout::output_section_name(relobj, orig_name, &len);
+ }
Stringpool::Key name_key;
name = this->namepool_.add_with_length(name, len, true, &name_key);
}
else
{
- os = this->choose_output_section(object, name, sh_type,
- shdr.get_sh_flags(), true,
- ORDER_INVALID, false);
+ // Plugins can choose to place one or more subsets of sections in
+ // unique segments and this is done by mapping these section subsets
+ // to unique output sections. Check if this section needs to be
+ // remapped to a unique output section.
+ Section_segment_map::iterator it
+ = this->section_segment_map_.find(Const_section_id(object, shndx));
+ if (it == this->section_segment_map_.end())
+ {
+ os = this->choose_output_section(object, name, sh_type,
+ shdr.get_sh_flags(), true,
+ ORDER_INVALID, false);
+ }
+ else
+ {
+ // We know the name of the output section, directly call
+ // get_output_section here by-passing choose_output_section.
+ elfcpp::Elf_Xword flags
+ = this->get_output_section_flags(shdr.get_sh_flags());
+
+ const char* os_name = it->second->name;
+ Stringpool::Key name_key;
+ os_name = this->namepool_.add(os_name, true, &name_key);
+ os = this->get_output_section(os_name, name_key, sh_type, flags,
+ ORDER_INVALID, false);
+ if (!os->is_unique_segment())
+ {
+ os->set_is_unique_segment();
+ os->set_extra_segment_flags(it->second->flags);
+ os->set_segment_alignment(it->second->align);
+ }
+ }
if (os == NULL)
return NULL;
}
return os;
}
+// Maps section SECN to SEGMENT s.
+void
+Layout::insert_section_segment_map(Const_section_id secn,
+ Unique_segment_info *s)
+{
+ gold_assert(this->unique_segment_for_sections_specified_);
+ this->section_segment_map_[secn] = s;
+}
+
// Handle a relocation section when doing a relocatable link.
template<int size, bool big_endian>
{
if (type == elfcpp::SHT_PROGBITS)
{
- if (strcmp(name, ".data.rel.ro") == 0)
+ if ((flags & elfcpp::SHF_TLS) != 0)
+ is_relro = true;
+ else if (strcmp(name, ".data.rel.ro") == 0)
is_relro = true;
else if (strcmp(name, ".data.rel.ro.local") == 0)
{
elfcpp::Elf_Word seg_flags = Layout::section_flags_to_segment(flags);
+ // If this output section's segment has extra flags that need to be set,
+ // coming from a linker plugin, do that.
+ seg_flags |= os->extra_segment_flags();
+
// Check for --section-start.
uint64_t addr;
bool is_address_set = parameters->options().section_start(os->name(), &addr);
// have to use a linker script.
Segment_list::const_iterator p;
- for (p = this->segment_list_.begin();
- p != this->segment_list_.end();
- ++p)
+ if (!os->is_unique_segment())
{
- if ((*p)->type() != elfcpp::PT_LOAD)
- continue;
- if (!parameters->options().omagic()
- && ((*p)->flags() & elfcpp::PF_W) != (seg_flags & elfcpp::PF_W))
- continue;
- if ((target->isolate_execinstr() || parameters->options().rosegment())
- && ((*p)->flags() & elfcpp::PF_X) != (seg_flags & elfcpp::PF_X))
- continue;
- // If -Tbss was specified, we need to separate the data and BSS
- // segments.
- if (parameters->options().user_set_Tbss())
- {
- if ((os->type() == elfcpp::SHT_NOBITS)
- == (*p)->has_any_data_sections())
- continue;
- }
- if (os->is_large_data_section() && !(*p)->is_large_data_segment())
- continue;
-
- if (is_address_set)
+ for (p = this->segment_list_.begin();
+ p != this->segment_list_.end();
+ ++p)
{
- if ((*p)->are_addresses_set())
- continue;
-
- (*p)->add_initial_output_data(os);
- (*p)->update_flags_for_output_section(seg_flags);
- (*p)->set_addresses(addr, addr);
- break;
- }
-
- (*p)->add_output_section_to_load(this, os, seg_flags);
- break;
- }
-
- if (p == this->segment_list_.end())
+ if ((*p)->type() != elfcpp::PT_LOAD)
+ continue;
+ if ((*p)->is_unique_segment())
+ continue;
+ if (!parameters->options().omagic()
+ && ((*p)->flags() & elfcpp::PF_W) != (seg_flags & elfcpp::PF_W))
+ continue;
+ if ((target->isolate_execinstr() || parameters->options().rosegment())
+ && ((*p)->flags() & elfcpp::PF_X) != (seg_flags & elfcpp::PF_X))
+ continue;
+ // If -Tbss was specified, we need to separate the data and BSS
+ // segments.
+ if (parameters->options().user_set_Tbss())
+ {
+ if ((os->type() == elfcpp::SHT_NOBITS)
+ == (*p)->has_any_data_sections())
+ continue;
+ }
+ if (os->is_large_data_section() && !(*p)->is_large_data_segment())
+ continue;
+
+ if (is_address_set)
+ {
+ if ((*p)->are_addresses_set())
+ continue;
+
+ (*p)->add_initial_output_data(os);
+ (*p)->update_flags_for_output_section(seg_flags);
+ (*p)->set_addresses(addr, addr);
+ break;
+ }
+
+ (*p)->add_output_section_to_load(this, os, seg_flags);
+ break;
+ }
+ }
+
+ if (p == this->segment_list_.end()
+ || os->is_unique_segment())
{
Output_segment* oseg = this->make_output_segment(elfcpp::PT_LOAD,
seg_flags);
oseg->add_output_section_to_load(this, os, seg_flags);
if (is_address_set)
oseg->set_addresses(addr, addr);
+ // Check if segment should be marked unique. For segments marked
+ // unique by linker plugins, set the new alignment if specified.
+ if (os->is_unique_segment())
+ {
+ oseg->set_is_unique_segment();
+ if (os->segment_alignment() != 0)
+ oseg->set_minimum_p_align(os->segment_alignment());
+ }
}
// If we see a loadable SHT_NOTE section, we create a PT_NOTE
// compatible with putting the segment headers and file headers into
// that segment.
if (parameters->options().user_set_Ttext()
- && parameters->options().Ttext() % target->common_pagesize() != 0)
+ && parameters->options().Ttext() % target->abi_pagesize() != 0)
{
load_seg = NULL;
phdr_seg = NULL;
while (target->may_relax()
&& target->relax(pass, input_objects, symtab, this, task));
+ // If there is a load segment that contains the file and program headers,
+ // provide a symbol __ehdr_start pointing there.
+ // A program can use this to examine itself robustly.
+ if (load_seg != NULL)
+ symtab->define_in_output_segment("__ehdr_start", NULL,
+ Symbol_table::PREDEFINED, load_seg, 0, 0,
+ elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
+ elfcpp::STV_DEFAULT, 0,
+ Symbol::SEGMENT_START, true);
+
// Set the file offsets of all the non-data sections we've seen so
// far which don't have to wait for the input sections. We need
// this in order to finalize local symbols in non-allocated
// We shouldn't get here--we shouldn't create segments which we
// can't distinguish. Unless of course we are using a weird linker
- // script or overlapping --section-start options.
+ // script or overlapping --section-start options. We could also get
+ // here if plugins want unique segments for subsets of sections.
gold_assert(this->script_options_->saw_phdrs_clause()
- || parameters->options().any_section_start());
+ || parameters->options().any_section_start()
+ || this->is_unique_segment_for_sections_specified());
return false;
}
if (!parameters->options().nmagic()
&& !parameters->options().omagic())
- (*p)->set_minimum_p_align(common_pagesize);
+ (*p)->set_minimum_p_align(abi_pagesize);
if (!are_addresses_set)
{
use_rel ? elfcpp::DT_REL : elfcpp::DT_RELA);
}
- if (dyn_rel != NULL && dyn_rel->output_section() != NULL)
+ if ((dyn_rel != NULL && dyn_rel->output_section() != NULL)
+ || (dynrel_includes_plt
+ && plt_rel != NULL
+ && plt_rel->output_section() != NULL))
{
+ bool have_dyn_rel = dyn_rel != NULL && dyn_rel->output_section() != NULL;
+ bool have_plt_rel = plt_rel != NULL && plt_rel->output_section() != NULL;
odyn->add_section_address(use_rel ? elfcpp::DT_REL : elfcpp::DT_RELA,
- dyn_rel->output_section());
- if (plt_rel != NULL
- && plt_rel->output_section() != NULL
- && dynrel_includes_plt)
- odyn->add_section_size(use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ,
+ (have_dyn_rel
+ ? dyn_rel->output_section()
+ : plt_rel->output_section()));
+ elfcpp::DT size_tag = use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ;
+ if (have_dyn_rel && have_plt_rel && dynrel_includes_plt)
+ odyn->add_section_size(size_tag,
dyn_rel->output_section(),
plt_rel->output_section());
+ else if (have_dyn_rel)
+ odyn->add_section_size(size_tag, dyn_rel->output_section());
else
- odyn->add_section_size(use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ,
- dyn_rel->output_section());
+ odyn->add_section_size(size_tag, plt_rel->output_section());
const int size = parameters->target().get_size();
elfcpp::DT rel_tag;
int rel_size;
}
odyn->add_constant(rel_tag, rel_size);
- if (parameters->options().combreloc())
+ if (parameters->options().combreloc() && have_dyn_rel)
{
size_t c = dyn_rel->relative_reloc_count();
if (c > 0)
// based on the GNU linker default ELF linker script.
#define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
+#define MAPPING_INIT_EXACT(f, t) { f, 0, t, sizeof(t) - 1 }
const Layout::Section_name_mapping Layout::section_name_mapping[] =
{
MAPPING_INIT(".text.", ".text"),
MAPPING_INIT(".rodata.", ".rodata"),
- MAPPING_INIT(".data.rel.ro.local", ".data.rel.ro.local"),
- MAPPING_INIT(".data.rel.ro", ".data.rel.ro"),
+ MAPPING_INIT(".data.rel.ro.local.", ".data.rel.ro.local"),
+ MAPPING_INIT_EXACT(".data.rel.ro.local", ".data.rel.ro.local"),
+ MAPPING_INIT(".data.rel.ro.", ".data.rel.ro"),
+ MAPPING_INIT_EXACT(".data.rel.ro", ".data.rel.ro"),
MAPPING_INIT(".data.", ".data"),
MAPPING_INIT(".bss.", ".bss"),
MAPPING_INIT(".tdata.", ".tdata"),
MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"),
};
#undef MAPPING_INIT
+#undef MAPPING_INIT_EXACT
const int Layout::section_name_mapping_count =
(sizeof(Layout::section_name_mapping)
const Section_name_mapping* psnm = section_name_mapping;
for (int i = 0; i < section_name_mapping_count; ++i, ++psnm)
{
- if (strncmp(name, psnm->from, psnm->fromlen) == 0)
+ if (psnm->fromlen > 0)
+ {
+ if (strncmp(name, psnm->from, psnm->fromlen) == 0)
+ {
+ *plen = psnm->tolen;
+ return psnm->to;
+ }
+ }
+ else
{
- *plen = psnm->tolen;
- return psnm->to;
+ if (strcmp(name, psnm->from) == 0)
+ {
+ *plen = psnm->tolen;
+ return psnm->to;
+ }
}
}