* layout.cc (Layout::choose_output_section): If we find an
	existing section, update the flags.
	(Layout::create_notes): New function, broken out of
	Layout::finalize.
	(Layout::finalize): Don't create note sections.
	(Layout::create_note): Don't crash if linker script discards
	section.
	(Layout::create_gold_note): Likewise.
	(Layout::create_build_id): Likewise.  Don't set
	after_input_sections on the section.
	(Layout::create_executable_stack_info): Remove target parameter.
	Change caller.
	* layout.h (class Layout): Declare create_notes.  Update
	declaration of create_executable_stack_info.
	* gold.cc (queue_middle_tasks): Call create_notes.
	* output.cc (Output_section::update_flags_for_input_section): Move
	here from output.h.  If SHF_ALLOC flag is newly set, mark address
	invalid.
	* output.h (Output_data::mark_address_invalid): New function.
	(class Output_section): Only declare, not define,
	update_flags_for_input_section.  Remove set_flags.
This commit is contained in:
Ian Lance Taylor 2009-06-24 19:48:51 +00:00
parent 554585003d
commit 9c547ec3ac
6 changed files with 83 additions and 22 deletions

View file

@ -1,3 +1,28 @@
2009-06-24 Ian Lance Taylor <iant@google.com>
PR 10156
* layout.cc (Layout::choose_output_section): If we find an
existing section, update the flags.
(Layout::create_notes): New function, broken out of
Layout::finalize.
(Layout::finalize): Don't create note sections.
(Layout::create_note): Don't crash if linker script discards
section.
(Layout::create_gold_note): Likewise.
(Layout::create_build_id): Likewise. Don't set
after_input_sections on the section.
(Layout::create_executable_stack_info): Remove target parameter.
Change caller.
* layout.h (class Layout): Declare create_notes. Update
declaration of create_executable_stack_info.
* gold.cc (queue_middle_tasks): Call create_notes.
* output.cc (Output_section::update_flags_for_input_section): Move
here from output.h. If SHF_ALLOC flag is newly set, mark address
invalid.
* output.h (Output_data::mark_address_invalid): New function.
(class Output_section): Only declare, not define,
update_flags_for_input_section. Remove set_flags.
2009-06-24 Ian Lance Taylor <iant@google.com>
* script-sections.cc (Output_section_definition::

View file

@ -386,6 +386,9 @@ queue_middle_tasks(const General_options& options,
// TODO: if this is too slow, do this as a task, rather than inline.
symtab->detect_odr_violations(task, options.output_file_name());
// Create any automatic note sections.
layout->create_notes();
// Create any output sections required by any linker script.
layout->create_script_sections();

View file

@ -416,7 +416,10 @@ Layout::choose_output_section(const Relobj* relobj, const char* name,
if (output_section_slot != NULL)
{
if (*output_section_slot != NULL)
return *output_section_slot;
{
(*output_section_slot)->update_flags_for_input_section(flags);
return *output_section_slot;
}
// We don't put sections found in the linker script into
// SECTION_NAME_MAP_. That keeps us from getting confused
@ -1028,6 +1031,16 @@ Layout::layout_gnu_stack(bool seen_gnu_stack, uint64_t gnu_stack_flags)
}
}
// Create automatic note sections.
void
Layout::create_notes()
{
this->create_gold_note();
this->create_executable_stack_info();
this->create_build_id();
}
// Create the dynamic sections which are needed before we read the
// relocs.
@ -1198,9 +1211,6 @@ Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab,
this->count_local_symbols(task, input_objects);
this->create_gold_note();
this->create_executable_stack_info(target);
this->create_build_id();
this->link_stabs_sections();
Output_segment* phdr_seg = NULL;
@ -1442,6 +1452,9 @@ Layout::create_note(const char* name, int note_type,
Output_section* os = this->choose_output_section(NULL, section_name,
elfcpp::SHT_NOTE,
flags, false);
if (os == NULL)
return NULL;
Output_section_data* posd = new Output_data_const_buffer(buffer, notehdrsz,
size / 8,
"** note header");
@ -1467,6 +1480,8 @@ Layout::create_gold_note()
Output_section *os = this->create_note("GNU", elfcpp::NT_GNU_GOLD_VERSION,
".note.gnu.gold-version", desc.size(),
false, &trailing_padding);
if (os == NULL)
return;
Output_section_data* posd = new Output_data_const(desc, 4);
os->add_output_section_data(posd);
@ -1491,7 +1506,7 @@ Layout::create_gold_note()
// library, we create a PT_GNU_STACK segment.
void
Layout::create_executable_stack_info(const Target* target)
Layout::create_executable_stack_info()
{
bool is_stack_executable;
if (parameters->options().is_execstack_set())
@ -1503,7 +1518,8 @@ Layout::create_executable_stack_info(const Target* target)
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();
is_stack_executable =
parameters->target().is_default_stack_executable();
else
is_stack_executable = false;
}
@ -1600,6 +1616,8 @@ Layout::create_build_id()
Output_section* os = this->create_note("GNU", elfcpp::NT_GNU_BUILD_ID,
".note.gnu.build-id", descsz, true,
&trailing_padding);
if (os == NULL)
return;
if (!desc.empty())
{
@ -1622,7 +1640,6 @@ Layout::create_build_id()
gold_assert(trailing_padding == 0);
this->build_id_note_ = new Output_data_zero_fill(descsz, 4);
os->add_output_section_data(this->build_id_note_);
os->set_after_input_sections();
}
}

View file

@ -208,6 +208,10 @@ class Layout
void
define_section_symbols(Symbol_table*);
// Create automatic note sections.
void
create_notes();
// Create sections for linker scripts.
void
create_script_sections()
@ -474,7 +478,7 @@ class Layout
// Record whether the stack must be executable.
void
create_executable_stack_info(const Target*);
create_executable_stack_info();
// Create a build ID note if needed.
void

View file

@ -1995,6 +1995,24 @@ Output_section::add_merge_input_section(Relobj* object, unsigned int shndx,
return true;
}
// Update the output section flags based on input section flags.
void
Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags)
{
// If we created the section with SHF_ALLOC clear, we set the
// address. If we are now setting the SHF_ALLOC flag, we need to
// undo that.
if ((this->flags_ & elfcpp::SHF_ALLOC) == 0
&& (flags & elfcpp::SHF_ALLOC) != 0)
this->mark_address_invalid();
this->flags_ |= (flags
& (elfcpp::SHF_WRITE
| elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR));
}
// Given an address OFFSET relative to the start of input section
// SHNDX in OBJECT, return whether this address is being included in
// the final link. This should only be called if SHNDX in OBJECT has

View file

@ -330,6 +330,13 @@ class Output_data
// Functions that child classes may call.
// Reset the address. The Output_section class needs this when an
// SHF_ALLOC input section is added to an output section which was
// formerly not SHF_ALLOC.
void
mark_address_invalid()
{ this->is_address_valid_ = false; }
// Set the size of the data.
void
set_data_size(off_t data_size)
@ -1948,22 +1955,9 @@ class Output_section : public Output_data
flags() const
{ return this->flags_; }
// Set the section flags. This may only be used with the Layout
// code when it is prepared to move the section to a different
// segment.
void
set_flags(elfcpp::Elf_Xword flags)
{ this->flags_ = flags; }
// Update the output section flags based on input section flags.
void
update_flags_for_input_section(elfcpp::Elf_Xword flags)
{
this->flags_ |= (flags
& (elfcpp::SHF_WRITE
| elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR));
}
update_flags_for_input_section(elfcpp::Elf_Xword flags);
// Return the entsize field.
uint64_t