#include "symtab.h"
#include "script.h"
#include "plugin.h"
+#include "incremental.h"
namespace gold
{
inline bool
Symbol::should_add_dynsym_entry(Symbol_table* symtab) const
{
+ // If the symbol is only present on plugin files, the plugin decided we
+ // don't need it.
+ if (!this->in_real_elf())
+ return false;
+
// If the symbol is used by a dynamic relocation, we need to add it.
if (this->needs_dynsym_entry())
return true;
this->record_weak_aliases(&object_symbols);
}
+// Add a symbol from a incremental object file.
+
+template<int size, bool big_endian>
+Symbol*
+Symbol_table::add_from_incrobj(
+ Object* obj,
+ const char* name,
+ const char* ver,
+ elfcpp::Sym<size, big_endian>* sym)
+{
+ unsigned int st_shndx = sym->get_st_shndx();
+ bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE;
+
+ Stringpool::Key ver_key = 0;
+ bool is_default_version = false;
+ bool is_forced_local = false;
+
+ Stringpool::Key name_key;
+ name = this->namepool_.add(name, true, &name_key);
+
+ Sized_symbol<size>* res;
+ res = this->add_from_object(obj, name, name_key, ver, ver_key,
+ is_default_version, *sym, st_shndx,
+ is_ordinary, st_shndx);
+
+ if (is_forced_local)
+ this->force_local(res);
+
+ return res;
+}
+
// This is used to sort weak aliases. We sort them first by section
// index, then by offset, then by weak ahead of strong.
return false;
}
+ // If the symbol is only present on plugin files, the plugin decided we
+ // don't need it.
+ if (!sym->in_real_elf())
+ {
+ gold_assert(!sym->has_symtab_index());
+ sym->set_symtab_index(-1U);
+ return false;
+ }
+
// Compute final symbol value.
Compute_final_value_status status;
Value_type value = this->compute_final_value(sym, &status);
// We check for ODR violations by looking for symbols with the same
// name for which the debugging information reports that they were
-// defined in different source locations. When comparing the source
+// defined in disjoint source locations. When comparing the source
// location, we consider instances with the same base filename to be
// the same. This is because different object files/shared libraries
// can include the same header file using different paths, and
// This struct is used to compare line information, as returned by
// Dwarf_line_info::one_addr2line. It implements a < comparison
-// operator used with std::set.
+// operator used with std::sort.
struct Odr_violation_compare
{
operator()(const std::string& s1, const std::string& s2) const
{
// Inputs should be of the form "dirname/filename:linenum" where
- // "dirname/" is optional. We want to compare just the filename.
+ // "dirname/" is optional. We want to compare just the filename:linenum.
- // Find the last '/' and ':' in each string.
+ // Find the last '/' in each string.
std::string::size_type s1begin = s1.rfind('/');
std::string::size_type s2begin = s2.rfind('/');
- std::string::size_type s1end = s1.rfind(':');
- std::string::size_type s2end = s2.rfind(':');
// If there was no '/' in a string, start at the beginning.
if (s1begin == std::string::npos)
s1begin = 0;
if (s2begin == std::string::npos)
s2begin = 0;
- // If the ':' appeared in the directory name, compare to the end
- // of the string.
- if (s1end < s1begin)
- s1end = s1.size();
- if (s2end < s2begin)
- s2end = s2.size();
- // Compare takes lengths, not end indices.
- return s1.compare(s1begin, s1end - s1begin,
- s2, s2begin, s2end - s2begin) < 0;
+ return s1.compare(s1begin, std::string::npos,
+ s2, s2begin, std::string::npos) < 0;
+ }
+};
+
+// Returns all of the lines attached to LOC, not just the one the
+// instruction actually came from.
+std::vector<std::string>
+Symbol_table::linenos_from_loc(const Task* task,
+ const Symbol_location& loc)
+{
+ // We need to lock the object in order to read it. This
+ // means that we have to run in a singleton Task. If we
+ // want to run this in a general Task for better
+ // performance, we will need one Task for object, plus
+ // appropriate locking to ensure that we don't conflict with
+ // other uses of the object. Also note, one_addr2line is not
+ // currently thread-safe.
+ Task_lock_obj<Object> tl(task, loc.object);
+
+ std::vector<std::string> result;
+ // 16 is the size of the object-cache that one_addr2line should use.
+ std::string canonical_result = Dwarf_line_info::one_addr2line(
+ loc.object, loc.shndx, loc.offset, 16, &result);
+ if (!canonical_result.empty())
+ result.push_back(canonical_result);
+ return result;
+}
+
+// OutputIterator that records if it was ever assigned to. This
+// allows it to be used with std::set_intersection() to check for
+// intersection rather than computing the intersection.
+struct Check_intersection
+{
+ Check_intersection()
+ : value_(false)
+ {}
+
+ bool had_intersection() const
+ { return this->value_; }
+
+ Check_intersection& operator++()
+ { return *this; }
+
+ Check_intersection& operator*()
+ { return *this; }
+
+ template<typename T>
+ Check_intersection& operator=(const T&)
+ {
+ this->value_ = true;
+ return *this;
}
+
+ private:
+ bool value_;
};
// Check candidate_odr_violations_ to find symbols with the same name
-// but apparently different definitions (different source-file/line-no).
+// but apparently different definitions (different source-file/line-no
+// for each line assigned to the first instruction).
void
Symbol_table::detect_odr_violations(const Task* task,
it != candidate_odr_violations_.end();
++it)
{
- const char* symbol_name = it->first;
- // Maps from symbol location to a sample object file we found
- // that location in. We use a sorted map so the location order
- // is deterministic, but we only store an arbitrary object file
- // to avoid copying lots of names.
- std::map<std::string, std::string, Odr_violation_compare> line_nums;
-
- for (Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
- locs = it->second.begin();
- locs != it->second.end();
- ++locs)
+ const char* const symbol_name = it->first;
+
+ std::string first_object_name;
+ std::vector<std::string> first_object_linenos;
+
+ Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
+ locs = it->second.begin();
+ const Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
+ locs_end = it->second.end();
+ for (; locs != locs_end && first_object_linenos.empty(); ++locs)
{
- // We need to lock the object in order to read it. This
- // means that we have to run in a singleton Task. If we
- // want to run this in a general Task for better
- // performance, we will need one Task for object, plus
- // appropriate locking to ensure that we don't conflict with
- // other uses of the object. Also note, one_addr2line is not
- // currently thread-safe.
- Task_lock_obj<Object> tl(task, locs->object);
- // 16 is the size of the object-cache that one_addr2line should use.
- std::string lineno = Dwarf_line_info::one_addr2line(
- locs->object, locs->shndx, locs->offset, 16);
- if (!lineno.empty())
- {
- std::string& sample_object = line_nums[lineno];
- if (sample_object.empty())
- sample_object = locs->object->name();
- }
+ // Save the line numbers from the first definition to
+ // compare to the other definitions. Ideally, we'd compare
+ // every definition to every other, but we don't want to
+ // take O(N^2) time to do this. This shortcut may cause
+ // false negatives that appear or disappear depending on the
+ // link order, but it won't cause false positives.
+ first_object_name = locs->object->name();
+ first_object_linenos = this->linenos_from_loc(task, *locs);
}
- if (line_nums.size() > 1)
+ // Sort by Odr_violation_compare to make std::set_intersection work.
+ std::sort(first_object_linenos.begin(), first_object_linenos.end(),
+ Odr_violation_compare());
+
+ for (; locs != locs_end; ++locs)
{
- gold_warning(_("while linking %s: symbol '%s' defined in multiple "
- "places (possible ODR violation):"),
- output_file_name, demangle(symbol_name).c_str());
- for (std::map<std::string, std::string>::const_iterator it2 =
- line_nums.begin();
- it2 != line_nums.end();
- ++it2)
- fprintf(stderr, _(" %s from %s\n"),
- it2->first.c_str(), it2->second.c_str());
+ std::vector<std::string> linenos =
+ this->linenos_from_loc(task, *locs);
+ // linenos will be empty if we couldn't parse the debug info.
+ if (linenos.empty())
+ continue;
+ // Sort by Odr_violation_compare to make std::set_intersection work.
+ std::sort(linenos.begin(), linenos.end(), Odr_violation_compare());
+
+ Check_intersection intersection_result =
+ std::set_intersection(first_object_linenos.begin(),
+ first_object_linenos.end(),
+ linenos.begin(),
+ linenos.end(),
+ Check_intersection(),
+ Odr_violation_compare());
+ if (!intersection_result.had_intersection())
+ {
+ gold_warning(_("while linking %s: symbol '%s' defined in "
+ "multiple places (possible ODR violation):"),
+ output_file_name, demangle(symbol_name).c_str());
+ // This only prints one location from each definition,
+ // which may not be the location we expect to intersect
+ // with another definition. We could print the whole
+ // set of locations, but that seems too verbose.
+ gold_assert(!first_object_linenos.empty());
+ gold_assert(!linenos.empty());
+ fprintf(stderr, _(" %s from %s\n"),
+ first_object_linenos[0].c_str(),
+ first_object_name.c_str());
+ fprintf(stderr, _(" %s from %s\n"),
+ linenos[0].c_str(),
+ locs->object->name().c_str());
+ // Only print one broken pair, to avoid needing to
+ // compare against a list of the disjoint definition
+ // locations we've found so far. (If we kept comparing
+ // against just the first one, we'd get a lot of
+ // redundant complaints about the second definition
+ // location.)
+ break;
+ }
}
}
// We only call one_addr2line() in this function, so we can clear its cache.
size_t* defined);
#endif
+#ifdef HAVE_TARGET_32_LITTLE
+template
+Symbol*
+Symbol_table::add_from_incrobj(
+ Object* obj,
+ const char* name,
+ const char* ver,
+ elfcpp::Sym<32, false>* sym);
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+Symbol*
+Symbol_table::add_from_incrobj(
+ Object* obj,
+ const char* name,
+ const char* ver,
+ elfcpp::Sym<32, true>* sym);
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+Symbol*
+Symbol_table::add_from_incrobj(
+ Object* obj,
+ const char* name,
+ const char* ver,
+ elfcpp::Sym<64, false>* sym);
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+Symbol*
+Symbol_table::add_from_incrobj(
+ Object* obj,
+ const char* name,
+ const char* ver,
+ elfcpp::Sym<64, true>* sym);
+#endif
+
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
template
void