* dwarf_reader.cc (Sized_dwarf_line_info): Include all lines,

	but mark earlier ones as non-canonical
	(offset_to_iterator): Update search target and example
	(do_addr2line): Return extra lines in a vector*
	(format_file_lineno): Extract from do_addr2line
	(one_addr2line): Add vector* out-param
	* dwarf_reader.h (Offset_to_lineno_entry): New field recording
	when a lineno entry appeared last for its instruction
	(Dwarf_line_info): Add vector* out-param
	* object.cc (Relocate_info): Pass NULL for the vector* out-param
	* symtab.cc (Odr_violation_compare): Include the lineno in the
	comparison again.
	(linenos_from_loc): New. Combine the canonical line for an
	address with its other lines.
	(True_if_intersect): New. Helper functor to make
	std::set_intersection a query.
	(detect_odr_violations): Compare sets of lines instead of just
	one line for each function. This became less deterministic, but
	has fewer false positives.
	* symtab.h: Declarations.
	* testsuite/Makefile.am (odr_violation2.o): Compile with -O2 to
	mix an optimized and non-optimized object in the same binary
	(odr_violation2.so): Same.
	* testsuite/Makefile.in: Regenerate from Makefile.am.
	* testsuite/debug_msg.cc (main): Make OdrDerived classes.
	* testsuite/debug_msg.sh: Update line numbers and add
	assertions.
	* testsuite/odr_violation1.cc: Use OdrDerived, in a
	non-optimized context.
	* testsuite/odr_violation2.cc: Make sure Ordering::operator()
	isn't inlined, and use OdrDerived in an optimized context.
	* testsuite/odr_header1.h: Defines OdrDerived, where
	optimization will change the
	first-instruction-in-the-destructor's file and line number.
	* testsuite/odr_header2.h: Defines OdrBase.

1 files changed, 33 insertions, 27 deletions

diff --git a/gold/symtab.h b/gold/symtab.h
index c0ae358..d350d1d 100644
--- a/gold/symtab.h
+++ b/gold/symtab.h
@@ -1560,6 +1560,33 @@ class Symbol_table
   typedef Unordered_map<Symbol_table_key, Symbol*, Symbol_table_hash,
 			Symbol_table_eq> Symbol_table_type;
 
+  // A map from symbol name (as a pointer into the namepool) to all
+  // the locations the symbols is (weakly) defined (and certain other
+  // conditions are met).  This map will be used later to detect
+  // possible One Definition Rule (ODR) violations.
+  struct Symbol_location
+  {
+    Object* object;         // Object where the symbol is defined.
+    unsigned int shndx;     // Section-in-object where the symbol is defined.
+    off_t offset;           // Offset-in-section where the symbol is defined.
+    bool operator==(const Symbol_location& that) const
+    {
+      return (this->object == that.object
+              && this->shndx == that.shndx
+              && this->offset == that.offset);
+    }
+  };
+
+  struct Symbol_location_hash
+  {
+    size_t operator()(const Symbol_location& loc) const
+    { return reinterpret_cast<uintptr_t>(loc.object) ^ loc.offset ^ loc.shndx; }
+  };
+
+  typedef Unordered_map<const char*,
+                        Unordered_set<Symbol_location, Symbol_location_hash> >
+  Odr_map;
+
   // Make FROM a forwarder symbol to TO.
   void
   make_forwarder(Symbol* from, Symbol* to);
@@ -1707,6 +1734,12 @@ class Symbol_table
   do_allocate_commons_list(Layout*, Commons_section_type, Commons_type*,
 			   Mapfile*, Sort_commons_order);
 
+  // Returns all of the lines attached to LOC, not just the one the
+  // instruction actually came from.  This helps the ODR checker avoid
+  // false positives.
+  static std::vector<std::string>
+  linenos_from_loc(const Task* task, const Symbol_location& loc);
+
   // Implement detect_odr_violations.
   template<int size, bool big_endian>
   void
@@ -1760,33 +1793,6 @@ class Symbol_table
   // they are defined.
   typedef Unordered_map<const Symbol*, Dynobj*> Copied_symbol_dynobjs;
 
-  // A map from symbol name (as a pointer into the namepool) to all
-  // the locations the symbols is (weakly) defined (and certain other
-  // conditions are met).  This map will be used later to detect
-  // possible One Definition Rule (ODR) violations.
-  struct Symbol_location
-  {
-    Object* object;         // Object where the symbol is defined.
-    unsigned int shndx;     // Section-in-object where the symbol is defined.
-    off_t offset;           // Offset-in-section where the symbol is defined.
-    bool operator==(const Symbol_location& that) const
-    {
-      return (this->object == that.object
-              && this->shndx == that.shndx
-              && this->offset == that.offset);
-    }
-  };
-
-  struct Symbol_location_hash
-  {
-    size_t operator()(const Symbol_location& loc) const
-    { return reinterpret_cast<uintptr_t>(loc.object) ^ loc.offset ^ loc.shndx; }
-  };
-
-  typedef Unordered_map<const char*,
-                        Unordered_set<Symbol_location, Symbol_location_hash> >
-  Odr_map;
-
   // We increment this every time we see a new undefined symbol, for
   // use in archive groups.
   size_t saw_undefined_;