// object.h -- support for an object file for linking in gold -*- C++ -*-
-// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
class General_options;
class Task;
+class Cref;
+class Archive;
class Layout;
class Output_section;
class Output_file;
class Output_symtab_xindex;
+class Pluginobj;
class Dynobj;
class Object_merge_map;
class Relocatable_relocs;
+class Symbols_data;
template<typename Stringpool_char>
class Stringpool_template;
Object(const std::string& name, Input_file* input_file, bool is_dynamic,
off_t offset = 0)
: name_(name), input_file_(input_file), offset_(offset), shnum_(-1U),
- is_dynamic_(is_dynamic), target_(NULL), xindex_(NULL)
+ is_dynamic_(is_dynamic), target_(NULL), xindex_(NULL), no_export_(false)
{ input_file->file().add_object(); }
virtual ~Object()
is_dynamic() const
{ return this->is_dynamic_; }
+ // Returns NULL for Objects that are not plugin objects. This method
+ // is overridden in the Pluginobj class.
+ Pluginobj*
+ pluginobj()
+ { return this->do_pluginobj(); }
+
// Return the target structure associated with this object.
Target*
target() const
{ return this->target_; }
+ // Get the file. We pass on const-ness.
+ Input_file*
+ input_file()
+ { return this->input_file_; }
+
+ const Input_file*
+ input_file() const
+ { return this->input_file_; }
+
// Lock the underlying file.
void
lock(const Task* t)
// Add symbol information to the global symbol table.
void
- add_symbols(Symbol_table* symtab, Read_symbols_data* sd)
- { this->do_add_symbols(symtab, sd); }
+ add_symbols(Symbol_table* symtab, Read_symbols_data* sd, Layout *layout)
+ { this->do_add_symbols(symtab, sd, layout); }
// Functions and types for the elfcpp::Elf_file interface. This
// permit us to use Object as the File template parameter for
// Read data from the underlying file.
void
- read(off_t start, section_size_type size, void* p) const
+ read(off_t start, section_size_type size, void* p)
{ this->input_file()->file().read(start + this->offset_, size, p); }
// Read multiple data from the underlying file.
clear_view_cache_marks()
{ this->input_file()->file().clear_view_cache_marks(); }
+ // Get the number of global symbols defined by this object, and the
+ // number of the symbols whose final definition came from this
+ // object.
+ void
+ get_global_symbol_counts(const Symbol_table* symtab, size_t* defined,
+ size_t* used) const
+ { this->do_get_global_symbol_counts(symtab, defined, used); }
+
+ // Set the target.
+ void
+ set_target(Target* target)
+ { this->target_ = target; }
+
+ // Return whether this object was found in a system directory.
+ bool
+ is_in_system_directory() const
+ { return this->input_file()->is_in_system_directory(); }
+
+ // Return whether we found this object by searching a directory.
+ bool
+ searched_for() const
+ { return this->input_file()->will_search_for(); }
+
+ bool
+ no_export() const
+ { return this->no_export_; }
+
+ void
+ set_no_export(bool value)
+ { this->no_export_ = value; }
+
protected:
+ // Returns NULL for Objects that are not plugin objects. This method
+ // is overridden in the Pluginobj class.
+ virtual Pluginobj*
+ do_pluginobj()
+ { return NULL; }
+
// Read the symbols--implemented by child class.
virtual void
do_read_symbols(Read_symbols_data*) = 0;
// Add symbol information to the global symbol table--implemented by
// child class.
virtual void
- do_add_symbols(Symbol_table*, Read_symbols_data*) = 0;
+ do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*) = 0;
// Return the location of the contents of a section. Implemented by
// child class.
virtual Xindex*
do_initialize_xindex() = 0;
- // Get the file. We pass on const-ness.
- Input_file*
- input_file()
- { return this->input_file_; }
-
- const Input_file*
- input_file() const
- { return this->input_file_; }
+ // Implement get_global_symbol_counts--implemented by child class.
+ virtual void
+ do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const = 0;
// Set the target.
void
Target* target_;
// Many sections for objects with more than SHN_LORESERVE sections.
Xindex* xindex_;
+ // True if exclude this object from automatic symbol export.
+ // This is used only for archive objects.
+ bool no_export_;
};
// Implement sized_target inline for efficiency. This approach breaks
public:
Relobj(const std::string& name, Input_file* input_file, off_t offset = 0)
: Object(name, input_file, false, offset),
- map_to_output_(),
- comdat_groups_(),
- kept_comdat_sections_(),
+ output_sections_(),
map_to_relocatable_relocs_(NULL),
object_merge_map_(NULL),
relocs_must_follow_section_writes_(false)
{ }
+ // During garbage collection, the Read_symbols_data pass for
+ // each object is stored as layout needs to be done after
+ // reloc processing.
+ Symbols_data*
+ get_symbols_data()
+ { return this->sd_; }
+
+ // Decides which section names have to be included in the worklist
+ // as roots.
+ bool
+ is_section_name_included(const char *name);
+
+ void
+ copy_symbols_data(Symbols_data* gc_sd, Read_symbols_data* sd,
+ unsigned int section_header_size);
+
+ void
+ set_symbols_data(Symbols_data* sd)
+ { this->sd_ = sd; }
+
+ // During garbage collection, the Read_relocs pass for all objects
+ // is done before scanning the relocs. In that case, this->rd_ is
+ // used to store the information from Read_relocs for each object.
+ // This data is also used to compute the list of relevant sections.
+ Read_relocs_data*
+ get_relocs_data()
+ { return this->rd_; }
+
+ void
+ set_relocs_data(Read_relocs_data* rd)
+ { this->rd_ = rd; }
+
+ virtual bool
+ is_output_section_offset_invalid(unsigned int shndx) const = 0;
+
// Read the relocs.
void
read_relocs(Read_relocs_data* rd)
{ return this->do_read_relocs(rd); }
+ // Process the relocs, during garbage collection only.
+ void
+ gc_process_relocs(const General_options& options, Symbol_table* symtab,
+ Layout* layout, Read_relocs_data* rd)
+ { return this->do_gc_process_relocs(options, symtab, layout, rd); }
+
// Scan the relocs and adjust the symbol table.
void
scan_relocs(const General_options& options, Symbol_table* symtab,
bool
is_section_included(unsigned int shndx) const
{
- gold_assert(shndx < this->map_to_output_.size());
- return this->map_to_output_[shndx].output_section != NULL;
+ gold_assert(shndx < this->output_sections_.size());
+ return this->output_sections_[shndx] != NULL;
}
- // Return whether an input section requires special
- // handling--whether it is not simply mapped from the input file to
- // the output file.
- bool
- is_section_specially_mapped(unsigned int shndx) const
+ // Given a section index, return the corresponding Output_section.
+ // The return value will be NULL if the section is not included in
+ // the link.
+ Output_section*
+ output_section(unsigned int shndx) const
{
- gold_assert(shndx < this->map_to_output_.size());
- return (this->map_to_output_[shndx].output_section != NULL
- && this->map_to_output_[shndx].offset == -1);
+ gold_assert(shndx < this->output_sections_.size());
+ return this->output_sections_[shndx];
}
- // Given a section index, return the corresponding Output_section
- // (which will be NULL if the section is not included in the link)
- // and set *POFF to the offset within that section. *POFF will be
- // set to -1 if the section requires special handling.
- inline Output_section*
- output_section(unsigned int shndx, section_offset_type* poff) const;
+ // Given a section index, return the offset in the Output_section.
+ // The return value will be -1U if the section is specially mapped,
+ // such as a merge section.
+ uint64_t
+ output_section_offset(unsigned int shndx) const
+ { return this->do_output_section_offset(shndx); }
// Set the offset of an input section within its output section.
void
- set_section_offset(unsigned int shndx, section_offset_type off)
- {
- gold_assert(shndx < this->map_to_output_.size());
- this->map_to_output_[shndx].offset = off;
- }
-
- // Return the output address of the input section SHNDX.
- uint64_t
- output_section_address(unsigned int shndx) const;
+ set_section_offset(unsigned int shndx, uint64_t off)
+ { this->do_set_section_offset(shndx, off); }
// Return true if we need to wait for output sections to be written
// before we can apply relocations. This is true if the object has
return (*this->map_to_relocatable_relocs_)[reloc_shndx];
}
- // Information needed to keep track of kept comdat groups. This is
- // simply a map from the section name to its section index. This may
- // not be a one-to-one mapping, but we ignore that possibility since
- // this is used only to attempt to handle stray relocations from
- // non-comdat debug sections that refer to comdat loadable sections.
- typedef Unordered_map<std::string, unsigned int> Comdat_group;
-
- // Find a comdat group table given its group section SHNDX.
- Comdat_group*
- find_comdat_group(unsigned int shndx) const
- {
- Comdat_group_table::const_iterator p =
- this->comdat_groups_.find(shndx);
- if (p != this->comdat_groups_.end())
- return p->second;
- return NULL;
- }
+ // Layout sections whose layout was deferred while waiting for
+ // input files from a plugin.
+ void
+ layout_deferred_sections(Layout* layout)
+ { this->do_layout_deferred_sections(layout); }
protected:
- // What we need to know to map an input section to an output
- // section. We keep an array of these, one for each input section,
- // indexed by the input section number.
- struct Map_to_output
- {
- // The output section. This is NULL if the input section is to be
- // discarded.
- Output_section* output_section;
- // The offset within the output section. This is -1 if the
- // section requires special handling.
- section_offset_type offset;
- };
-
- // A map from group section index to the table of group members.
- typedef std::map<unsigned int, Comdat_group*> Comdat_group_table;
-
- // To keep track of discarded comdat sections, we need to map a member
- // section index to the object and section index of the corresponding
- // kept section.
- struct Kept_comdat_section
- {
- Kept_comdat_section(Relobj* object, unsigned int shndx)
- : object_(object), shndx_(shndx)
- { }
- Relobj* object_;
- unsigned int shndx_;
- };
- typedef std::map<unsigned int, Kept_comdat_section*>
- Kept_comdat_section_table;
+ // The output section to be used for each input section, indexed by
+ // the input section number. The output section is NULL if the
+ // input section is to be discarded.
+ typedef std::vector<Output_section*> Output_sections;
// Read the relocs--implemented by child class.
virtual void
do_read_relocs(Read_relocs_data*) = 0;
+ // Process the relocs--implemented by child class.
+ virtual void
+ do_gc_process_relocs(const General_options&, Symbol_table*, Layout*,
+ Read_relocs_data*) = 0;
+
// Scan the relocs--implemented by child class.
virtual void
do_scan_relocs(const General_options&, Symbol_table*, Layout*,
do_relocate(const General_options& options, const Symbol_table* symtab,
const Layout*, Output_file* of) = 0;
- // Return the vector mapping input sections to output sections.
- std::vector<Map_to_output>&
- map_to_output()
- { return this->map_to_output_; }
+ // Get the offset of a section--implemented by child class.
+ virtual uint64_t
+ do_output_section_offset(unsigned int shndx) const = 0;
- const std::vector<Map_to_output>&
- map_to_output() const
- { return this->map_to_output_; }
+ // Set the offset of a section--implemented by child class.
+ virtual void
+ do_set_section_offset(unsigned int shndx, uint64_t off) = 0;
- // Record a new comdat group whose group section index is SHNDX.
- void
- add_comdat_group(unsigned int shndx, Comdat_group* group)
- { this->comdat_groups_[shndx] = group; }
+ // Layout sections whose layout was deferred while waiting for
+ // input files from a plugin--implemented by child class.
+ virtual void
+ do_layout_deferred_sections(Layout*) = 0;
- // Record a mapping from discarded section SHNDX to the corresponding
- // kept section.
- void
- set_kept_comdat_section(unsigned int shndx, Kept_comdat_section* kept)
- {
- this->kept_comdat_sections_[shndx] = kept;
- }
+ // Return the vector mapping input sections to output sections.
+ Output_sections&
+ output_sections()
+ { return this->output_sections_; }
- // Find the kept section corresponding to the discarded section SHNDX.
- Kept_comdat_section*
- get_kept_comdat_section(unsigned int shndx) const
- {
- Kept_comdat_section_table::const_iterator p =
- this->kept_comdat_sections_.find(shndx);
- if (p == this->kept_comdat_sections_.end())
- return NULL;
- return p->second;
- }
+ const Output_sections&
+ output_sections() const
+ { return this->output_sections_; }
// Set the size of the relocatable relocs array.
void
private:
// Mapping from input sections to output section.
- std::vector<Map_to_output> map_to_output_;
- // Table of kept comdat groups.
- Comdat_group_table comdat_groups_;
- // Table mapping discarded comdat sections to corresponding kept sections.
- Kept_comdat_section_table kept_comdat_sections_;
+ Output_sections output_sections_;
// Mapping from input section index to the information recorded for
// the relocations. This is only used for a relocatable link.
std::vector<Relocatable_relocs*>* map_to_relocatable_relocs_;
// Whether we need to wait for output sections to be written before
// we can apply relocations.
bool relocs_must_follow_section_writes_;
+ // Used to store the relocs data computed by the Read_relocs pass.
+ // Used during garbage collection of unused sections.
+ Read_relocs_data* rd_;
+ // Used to store the symbols data computed by the Read_symbols pass.
+ // Again used during garbage collection when laying out referenced
+ // sections.
+ gold::Symbols_data *sd_;
};
-// Implement Object::output_section inline for efficiency.
-inline Output_section*
-Relobj::output_section(unsigned int shndx, section_offset_type* poff) const
-{
- gold_assert(shndx < this->map_to_output_.size());
- const Map_to_output& mo(this->map_to_output_[shndx]);
- *poff = mo.offset;
- return mo.output_section;
-}
-
// This class is used to handle relocations against a section symbol
// in an SHF_MERGE section. For such a symbol, we need to know the
// addend of the relocation before we can determine the final value.
Value
value(const Relobj* object, unsigned int input_shndx, Value addend) const
{
- Value input_offset = this->input_value_ + addend;
+ // This is a relocation against a section symbol. ADDEND is the
+ // offset in the section. The result should be the start of some
+ // merge area. If the object file wants something else, it should
+ // use a regular symbol rather than a section symbol.
+ // Unfortunately, PR 6658 shows a case in which the object file
+ // refers to the section symbol, but uses a negative ADDEND to
+ // compensate for a PC relative reloc. We can't handle the
+ // general case. However, we can handle the special case of a
+ // negative addend, by assuming that it refers to the start of the
+ // section. Of course, that means that we have to guess when
+ // ADDEND is negative. It is normal to see a 32-bit value here
+ // even when the template parameter size is 64, as 64-bit object
+ // file formats have 32-bit relocations. We know this is a merge
+ // section, so we know it has to fit into memory. So we assume
+ // that we won't see a value larger than a large 32-bit unsigned
+ // value. This will break objects with very very large merge
+ // sections; they probably break in other ways anyhow.
+ Value input_offset = this->input_value_;
+ if (addend < 0xffffff00)
+ {
+ input_offset += addend;
+ addend = 0;
+ }
typename Output_addresses::const_iterator p =
this->output_addresses_.find(input_offset);
if (p != this->output_addresses_.end())
- return p->second;
+ return p->second + addend;
- return this->value_from_output_section(object, input_shndx, input_offset);
+ return (this->value_from_output_section(object, input_shndx, input_offset)
+ + addend);
}
private:
typedef std::vector<Symbol*> Symbols;
typedef std::vector<Symbol_value<size> > Local_values;
+ static const Address invalid_address = static_cast<Address>(0) - 1;
+
Sized_relobj(const std::string& name, Input_file* input_file, off_t offset,
const typename elfcpp::Ehdr<size, big_endian>&);
~Sized_relobj();
+ // Checks if the offset of input section SHNDX within its output
+ // section is invalid.
+ bool
+ is_output_section_offset_invalid(unsigned int shndx) const
+ { return this->get_output_section_offset(shndx) == invalid_address; }
+
// Set up the object file based on the ELF header.
void
setup(const typename elfcpp::Ehdr<size, big_endian>&);
+ // Return the number of symbols. This is only valid after
+ // Object::add_symbols has been called.
+ unsigned int
+ symbol_count() const
+ { return this->local_symbol_count_ + this->symbols_.size(); }
+
// If SYM is the index of a global symbol in the object file's
// symbol table, return the Symbol object. Otherwise, return NULL.
Symbol*
}
}
+ // Get the offset of input section SHNDX within its output section.
+ // This is -1 if the input section requires a special mapping, such
+ // as a merge section. The output section can be found in the
+ // output_sections_ field of the parent class Relobj.
+ Address
+ get_output_section_offset(unsigned int shndx) const
+ {
+ gold_assert(shndx < this->section_offsets_.size());
+ return this->section_offsets_[shndx];
+ }
+
// Return the name of the symbol that spans the given offset in the
// specified section in this object. This is used only for error
// messages and is not particularly efficient.
void
do_layout(Symbol_table*, Layout*, Read_symbols_data*);
+ // Layout sections whose layout was deferred while waiting for
+ // input files from a plugin.
+ void
+ do_layout_deferred_sections(Layout*);
+
// Add the symbols to the symbol table.
void
- do_add_symbols(Symbol_table*, Read_symbols_data*);
+ do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*);
// Read the relocs.
void
do_read_relocs(Read_relocs_data*);
+ // Process the relocs to find list of referenced sections. Used only
+ // during garbage collection.
+ void
+ do_gc_process_relocs(const General_options&, Symbol_table*, Layout*,
+ Read_relocs_data*);
+
// Scan the relocs and adjust the symbol table.
void
do_scan_relocs(const General_options&, Symbol_table*, Layout*,
Xindex*
do_initialize_xindex();
+ // Get symbol counts.
+ void
+ do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const;
+
+ // Get the offset of a section.
+ uint64_t
+ do_output_section_offset(unsigned int shndx) const
+ {
+ Address off = this->get_output_section_offset(shndx);
+ if (off == invalid_address)
+ return -1ULL;
+ return off;
+ }
+
+ // Set the offset of a section.
+ void
+ do_set_section_offset(unsigned int shndx, uint64_t off)
+ {
+ gold_assert(shndx < this->section_offsets_.size());
+ this->section_offsets_[shndx] = convert_types<Address, uint64_t>(off);
+ }
+
private:
// For convenience.
typedef Sized_relobj<size, big_endian> This;
static const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
typedef elfcpp::Shdr<size, big_endian> Shdr;
+ // To keep track of discarded comdat sections, we need to map a member
+ // section index to the object and section index of the corresponding
+ // kept section.
+ struct Kept_comdat_section
+ {
+ Kept_comdat_section(Relobj* a_object, unsigned int a_shndx)
+ : object(a_object), shndx(a_shndx)
+ { }
+ Relobj* object;
+ unsigned int shndx;
+ };
+ typedef std::map<unsigned int, Kept_comdat_section>
+ Kept_comdat_section_table;
+
// Adjust a section index if necessary.
unsigned int
adjust_shndx(unsigned int shndx)
include_linkonce_section(Layout*, unsigned int, const char*,
const elfcpp::Shdr<size, big_endian>&);
+ // Layout an input section.
+ void
+ layout_section(Layout* layout, unsigned int shndx, const char* name,
+ typename This::Shdr& shdr, unsigned int reloc_shndx,
+ unsigned int reloc_type);
+
// Views and sizes when relocating.
struct View_size
{
void
emit_relocs(const Relocate_info<size, big_endian>*, unsigned int,
unsigned int sh_type, const unsigned char* prelocs,
- size_t reloc_count, Output_section*, off_t output_offset,
+ size_t reloc_count, Output_section*, Address output_offset,
unsigned char* view, Address address,
section_size_type view_size,
unsigned char* reloc_view, section_size_type reloc_view_size);
void
emit_relocs_reltype(const Relocate_info<size, big_endian>*, unsigned int,
const unsigned char* prelocs, size_t reloc_count,
- Output_section*, off_t output_offset,
+ Output_section*, Address output_offset,
unsigned char* view, Address address,
section_size_type view_size,
unsigned char* reloc_view,
this->local_got_offsets_.clear();
}
+ // Record a mapping from discarded section SHNDX to the corresponding
+ // kept section.
+ void
+ set_kept_comdat_section(unsigned int shndx, Relobj* kept_object,
+ unsigned int kept_shndx)
+ {
+ Kept_comdat_section kept(kept_object, kept_shndx);
+ this->kept_comdat_sections_.insert(std::make_pair(shndx, kept));
+ }
+
+ // Find the kept section corresponding to the discarded section
+ // SHNDX. Return true if found.
+ bool
+ get_kept_comdat_section(unsigned int shndx, Relobj** kept_object,
+ unsigned int* kept_shndx) const
+ {
+ typename Kept_comdat_section_table::const_iterator p =
+ this->kept_comdat_sections_.find(shndx);
+ if (p == this->kept_comdat_sections_.end())
+ return false;
+ *kept_object = p->second.object;
+ *kept_shndx = p->second.shndx;
+ return true;
+ }
+
// The GOT offsets of local symbols. This map also stores GOT offsets
// for tp-relative offsets for TLS symbols.
typedef Unordered_map<unsigned int, Got_offset_list*> Local_got_offsets;
};
typedef Unordered_map<unsigned int, Tls_got_entry> Local_tls_got_offsets;
+ // Saved information for sections whose layout was deferred.
+ struct Deferred_layout
+ {
+ static const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
+ Deferred_layout(unsigned int shndx, const char* name,
+ const unsigned char* pshdr,
+ unsigned int reloc_shndx, unsigned int reloc_type)
+ : shndx_(shndx), name_(name), reloc_shndx_(reloc_shndx),
+ reloc_type_(reloc_type)
+ {
+ memcpy(this->shdr_data_, pshdr, shdr_size);
+ }
+ unsigned int shndx_;
+ std::string name_;
+ unsigned int reloc_shndx_;
+ unsigned int reloc_type_;
+ unsigned char shdr_data_[shdr_size];
+ };
+
// General access to the ELF file.
elfcpp::Elf_file<size, big_endian, Object> elf_file_;
// Index of SHT_SYMTAB section.
unsigned int output_local_dynsym_count_;
// The entries in the symbol table for the external symbols.
Symbols symbols_;
+ // Number of symbols defined in object file itself.
+ size_t defined_count_;
// File offset for local symbols.
off_t local_symbol_offset_;
// File offset for local dynamic symbols.
// GOT offsets for local non-TLS symbols, and tp-relative offsets
// for TLS symbols, indexed by symbol number.
Local_got_offsets local_got_offsets_;
+ // For each input section, the offset of the input section in its
+ // output section. This is INVALID_ADDRESS if the input section requires a
+ // special mapping.
+ std::vector<Address> section_offsets_;
+ // Table mapping discarded comdat sections to corresponding kept sections.
+ Kept_comdat_section_table kept_comdat_sections_;
// Whether this object has a GNU style .eh_frame section.
bool has_eh_frame_;
+ // If this object has a GNU style .eh_frame section that is discarded in
+ // output, record the index here. Otherwise it is -1U.
+ unsigned int discarded_eh_frame_shndx_;
+ // The list of sections whose layout was deferred.
+ std::vector<Deferred_layout> deferred_layout_;
};
// A class to manage the list of all objects.
{
public:
Input_objects()
- : relobj_list_(), dynobj_list_(), sonames_(), system_library_directory_()
+ : relobj_list_(), dynobj_list_(), sonames_(), cref_(NULL)
{ }
// The type of the list of input relocateable objects.
bool
add_object(Object*);
+ // Start processing an archive.
+ void
+ archive_start(Archive*);
+
+ // Stop processing an archive.
+ void
+ archive_stop(Archive*);
+
// For each dynamic object, check whether we've seen all of its
// explicit dependencies.
void
bool
found_in_system_library_directory(const Object*) const;
+ // Print symbol counts.
+ void
+ print_symbol_counts(const Symbol_table*) const;
+
// Iterate over all regular objects.
Relobj_iterator
Dynobj_list dynobj_list_;
// SONAMEs that we have seen.
Unordered_set<std::string> sonames_;
- // The directory in which we find the libc.so.
- std::string system_library_directory_;
+ // Manage cross-references if requested.
+ Cref* cref_;
};
// Some of the information we pass to the relocation routines. We
location(size_t relnum, off_t reloffset) const;
};
+// Return whether INPUT_FILE contains an ELF object start at file
+// offset OFFSET. This sets *START to point to a view of the start of
+// the file. It sets *READ_SIZE to the number of bytes in the view.
+
+extern bool
+is_elf_object(Input_file* input_file, off_t offset,
+ const unsigned char** start, int *read_size);
+
// Return an Object appropriate for the input file. P is BYTES long,
-// and holds the ELF header.
+// and holds the ELF header. If PUNCONFIGURED is not NULL, then if
+// this sees an object the linker is not configured to support, it
+// sets *PUNCONFIGURED to true and returns NULL without giving an
+// error message.
extern Object*
make_elf_object(const std::string& name, Input_file*,
off_t offset, const unsigned char* p,
- section_offset_type bytes);
+ section_offset_type bytes, bool* punconfigured);
} // end namespace gold