// script.h -- handle linker scripts for gold -*- C++ -*-
-// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+// Copyright (C) 2006-2019 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
#include <string>
#include <vector>
+#include "elfcpp.h"
#include "script-sections.h"
namespace gold
struct Version_dependency_list;
struct Version_expression_list;
struct Version_tree;
+struct Version_expression;
+class Lazy_demangler;
+class Incremental_script_entry;
// This class represents an expression in a linker script.
// value is defined. If the value is absolute *RESULT_SECTION will
// be NULL. Note that the returned value is still an absolute
// value; to get a section relative value the caller must subtract
- // the section address.
+ // the section address. If RESULT_ALIGNMENT is not NULL, this sets
+ // *RESULT_ALIGNMENT to the alignment of the value of that alignment
+ // is larger than *RESULT_ALIGNMENT; this will only be non-zero if
+ // this is an ALIGN expression. If IS_SECTION_DOT_ASSIGMENT is true,
+ // we are evaluating an assignment to dot within an output section,
+ // and an absolute value should be interpreted as an offset within
+ // the section.
uint64_t
eval_with_dot(const Symbol_table*, const Layout*, bool check_assertions,
uint64_t dot_value, Output_section* dot_section,
- Output_section** result_section);
+ Output_section** result_section, uint64_t* result_alignment,
+ bool is_section_dot_assignment);
// Return the value of an expression which may or may not be
// permitted to refer to the dot symbol, depending on
- // is_dot_available.
+ // is_dot_available. If IS_SECTION_DOT_ASSIGMENT is true,
+ // we are evaluating an assignment to dot within an output section,
+ // and an absolute value should be interpreted as an offset within
+ // the section.
uint64_t
eval_maybe_dot(const Symbol_table*, const Layout*, bool check_assertions,
bool is_dot_available, uint64_t dot_value,
Output_section* dot_section,
- Output_section** result_section);
+ Output_section** result_section, uint64_t* result_alignment,
+ elfcpp::STT* type, elfcpp::STV* vis, unsigned char* nonvis,
+ bool is_section_dot_assignment, bool* is_valid_pointer);
// Print the expression to the FILE. This is for debugging.
virtual void
virtual uint64_t
value(const Expression_eval_info*) = 0;
+ // Sets all symbols used in expressions as seen in a real ELF object.
+ virtual void
+ set_expr_sym_in_real_elf(Symbol_table*) const
+ { return; }
+
private:
// May not be copied.
Expression(const Expression&);
Expression& operator=(const Expression&);
};
-
// Version_script_info stores information parsed from the version
// script, either provided by --version-script or as part of a linker
// script. A single Version_script_info object per target is owned by
{ return this->version_trees_.empty(); }
// If there is a version associated with SYMBOL, return true, and
- // set *VERSION to the version. Otherwise, return false.
+ // set *VERSION to the version, and *IS_GLOBAL to whether the symbol
+ // should be global. Otherwise, return false.
bool
- get_symbol_version(const char* symbol, std::string* version) const
- { return this->get_symbol_version_helper(symbol, true, version); }
+ get_symbol_version(const char* symbol, std::string* version,
+ bool* is_global) const;
// Return whether this symbol matches the local: section of some
// version.
bool
symbol_is_local(const char* symbol) const
- { return this->get_symbol_version_helper(symbol, false, NULL); }
+ {
+ bool is_global;
+ return (this->get_symbol_version(symbol, NULL, &is_global)
+ && !is_global);
+ }
// Return the names of versions defined in the version script.
std::vector<std::string>
bool check_global,
std::string* pversion) const;
- void
- matched_symbol(const Version_tree*, const char*) const;
+ // Fast lookup information for a given language.
+
+ // We map from exact match strings to Version_tree's. Historically
+ // version scripts sometimes have the same symbol multiple times,
+ // which is ambiguous. We warn about that case by storing the
+ // second Version_tree we see.
+ struct Version_tree_match
+ {
+ Version_tree_match(const Version_tree* r, bool ig,
+ const Version_expression* e)
+ : real(r), is_global(ig), expression(e), ambiguous(NULL)
+ { }
+
+ // The Version_tree that we return.
+ const Version_tree* real;
+ // True if this is a global match for the REAL member, false if it
+ // is a local match.
+ bool is_global;
+ // Point back to the Version_expression for which we created this
+ // match.
+ const Version_expression* expression;
+ // If not NULL, another Version_tree that defines the symbol.
+ const Version_tree* ambiguous;
+ };
+
+ // Map from an exact match string to a Version_tree.
+
+ typedef Unordered_map<std::string, Version_tree_match> Exact;
// Fast lookup information for a glob pattern.
struct Glob
{
Glob()
- : pattern(NULL), version(NULL)
+ : expression(NULL), version(NULL), is_global(false)
{ }
- Glob(const char* p, const Version_tree* v)
- : pattern(p), version(v)
+ Glob(const Version_expression* e, const Version_tree* v, bool ig)
+ : expression(e), version(v), is_global(ig)
{ }
- // A pointer to the glob pattern. The pattern itself lives in a
- // Version_expression structure.
- const char* pattern;
+ // A pointer to the version expression holding the pattern to
+ // match and the language to use for demangling the symbol before
+ // doing the match.
+ const Version_expression* expression;
// The Version_tree we use if this pattern matches.
const Version_tree* version;
+ // True if this is a global symbol.
+ bool is_global;
};
- // Fast lookup information for a given language.
+ typedef std::vector<Glob> Globs;
- typedef Unordered_map<std::string, const Version_tree*> Exact;
+ bool
+ unquote(std::string*) const;
- struct Lookup
- {
- // A hash table of all exact match strings mapping to a
- // Version_tree.
- Exact exact;
- // A vector of glob patterns mapping to Version_trees.
- std::vector<Glob> globs;
- };
+ void
+ add_exact_match(const std::string&, const Version_tree*, bool is_global,
+ const Version_expression*, Exact*);
void
build_expression_list_lookup(const Version_expression_list*,
- const Version_tree*, Lookup**);
+ const Version_tree*, bool);
+
+ const char*
+ get_name_to_match(const char*, int,
+ Lazy_demangler*, Lazy_demangler*) const;
// All the version dependencies we allocate.
std::vector<Version_dependency_list*> dependency_lists_;
std::vector<Version_expression_list*> expression_lists_;
// The list of versions.
std::vector<Version_tree*> version_trees_;
- // Lookup information for global symbols, by language.
- Lookup* globals_[LANGUAGE_COUNT];
- // Lookup information for local symbols, by language.
- Lookup* locals_[LANGUAGE_COUNT];
+ // Exact matches for global symbols, by language.
+ Exact* exact_[LANGUAGE_COUNT];
+ // A vector of glob patterns mapping to Version_trees.
+ Globs globs_;
+ // The default version to use, if there is one. This is from a
+ // pattern of "*".
+ const Version_tree* default_version_;
+ // True if the default version is global.
+ bool default_is_global_;
// Whether this has been finalized.
bool is_finalized_;
};
void
finalize(Symbol_table*, const Layout*);
+ bool
+ is_defsym() const
+ { return is_defsym_; }
+
+ Expression *
+ value() const
+ { return val_; }
+
// Finalize the symbol value when it can refer to the dot symbol.
void
finalize_with_dot(Symbol_table*, const Layout*, uint64_t dot_value,
Output_section* dot_section);
- // Set the symbol value, but only if the value is absolute. This is
- // used while processing a SECTIONS clause. We assume that dot is
- // an absolute value here. We do not check assertions.
+ // Set the symbol value, but only if the value is absolute or relative to
+ // DOT_SECTION. This is used while processing a SECTIONS clause.
+ // We assume that dot is an absolute value here. We do not check assertions.
void
set_if_absolute(Symbol_table*, const Layout*, bool is_dot_available,
- uint64_t dot_value);
+ uint64_t dot_value, Output_section* dot_section);
+
+ const std::string&
+ name() const
+ { return this->name_; }
// Print the assignment to the FILE. This is for debugging.
void
add_symbol_assignment(const char* name, size_t length, bool is_defsym,
Expression* value, bool provide, bool hidden);
+ // Look for an assigned symbol.
+ bool
+ is_pending_assignment(const char* name);
+
+ // Add a reference to a symbol.
+ void
+ add_symbol_reference(const char* name, size_t length);
+
// Add an assertion.
void
add_assertion(Expression* check, const char* message, size_t messagelen);
bool
define_symbol(const char* definition);
+ // Populates the set with symbol names used in LHS of defsym.
+ void
+ find_defsym_defs(Unordered_set<std::string>&);
+
+ // Set symbols used in defsym expressions as seen in a real ELF object.
+ void set_defsym_uses_in_real_elf(Symbol_table*) const;
+
// Create sections required by any linker scripts.
void
create_script_sections(Layout*);
void
add_symbols_to_table(Symbol_table*);
+ // Used to iterate over symbols which are referenced in expressions
+ // but not defined.
+ typedef Unordered_set<std::string>::const_iterator referenced_const_iterator;
+
+ referenced_const_iterator
+ referenced_begin() const
+ { return this->symbol_references_.begin(); }
+
+ referenced_const_iterator
+ referenced_end() const
+ { return this->symbol_references_.end(); }
+
+ // Return whether a symbol is referenced but not defined.
+ bool
+ is_referenced(const std::string& name) const
+ {
+ return (this->symbol_references_.find(name)
+ != this->symbol_references_.end());
+ }
+
+ // Return whether there are any symbols which were referenced but
+ // not defined.
+ bool
+ any_unreferenced() const
+ { return !this->symbol_references_.empty(); }
+
// Finalize the symbol values. Also check assertions.
void
finalize_symbols(Symbol_table*, const Layout*);
// SECTIONS clause.
typedef std::vector<Symbol_assignment*> Symbol_assignments;
- // We keep a list of all assertions whcih occur outside of a
+ // We keep a list of all assertions which occur outside of a
// SECTIONS clause.
typedef std::vector<Script_assertion*> Assertions;
std::string entry_;
// Symbols to set.
Symbol_assignments symbol_assignments_;
+ // Symbols defined in an expression, for faster lookup.
+ Unordered_set<std::string> symbol_definitions_;
+ // Symbols referenced in an expression.
+ Unordered_set<std::string> symbol_references_;
// Assertions to check.
Assertions assertions_;
// Version information parsed from a version script.
Script_sections script_sections_;
};
-// Information about a script input that will persist during the whole linker
-// run. Needed only during an incremental build to retrieve the input files
-// added by this script.
-
-class Script_info
-{
- public:
- Script_info(Input_arguments* inputs)
- : inputs_(inputs)
- { }
-
- // Returns the input files included because of this script.
- Input_arguments*
- inputs()
- { return this->inputs_; }
-
- private:
- Input_arguments* inputs_;
-};
-
// FILE was found as an argument on the command line, but was not
// recognized as an ELF file. Try to read it as a script. Return
// true if the file was handled. This has to handle /usr/lib/libc.so