2016-04-14 Basile Starynkevitch <basile@starynkevitch.net>

	{{merging with even more of GCC 6, using subversion 1.9
	svn merge -r228401:229500 ^/trunk
	}}



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/melt-branch@234985 138bc75d-0d04-0410-961f-82ee72b054a4

10 files changed, 193 insertions, 120 deletions

diff --git a/gcc/go/ChangeLog b/gcc/go/ChangeLog
index be1fd0cb09b..f25c898782b 100644
--- a/gcc/go/ChangeLog
+++ b/gcc/go/ChangeLog
@@ -1,3 +1,11 @@
+2015-10-20  Alan Modra  <amodra@gmail.com>
+
+	PR go/66870
+	* gospec.c (saw_opt_m32): Rename to..
+	(is_m64): ..this, initialised by TARGET_CAN_SPLIT_STACK_64BIT.
+	Update uses.
+	(lang_specific_driver): Set is_m64 if OPT_m64, clear if OPT_m32.
+
 2015-10-01  Ian Lance Taylor  <iant@google.com>
 
 	PR go/66870
diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index eaa24dcbfef..6fcd18593a6 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-f187e13b712824b08f2a8833033840cd52a3b95a
+11e249a59e8c627fe9c2938c38e39cb1efefb1fb
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/gcc/go/gofrontend/expressions.cc b/gcc/go/gofrontend/expressions.cc
index 56bbf619bd8..0d25dda1f44 100644
--- a/gcc/go/gofrontend/expressions.cc
+++ b/gcc/go/gofrontend/expressions.cc
@@ -4909,14 +4909,7 @@ Binary_expression::do_lower(Gogo* gogo, Named_object*,
 	    Numeric_constant nc;
 	    if (!Binary_expression::eval_constant(op, &left_nc, &right_nc,
 						  location, &nc))
-              {
-                if (nc.is_invalid())
-                  {
-                    go_assert(saw_errors());
-                    return Expression::make_error(location);
-                  }
                 return this;
-              }
 	    return nc.expression(location);
 	  }
       }
@@ -5200,13 +5193,13 @@ Binary_expression::do_flatten(Gogo* gogo, Named_object*,
       || (is_idiv_op
 	  && (gogo->check_divide_by_zero() || gogo->check_divide_overflow())))
     {
-      if (!this->left_->is_variable())
+      if (!this->left_->is_variable() && !this->left_->is_constant())
         {
           temp = Statement::make_temporary(NULL, this->left_, loc);
           inserter->insert(temp);
           this->left_ = Expression::make_temporary_reference(temp, loc);
         }
-      if (!this->right_->is_variable())
+      if (!this->right_->is_variable() && !this->right_->is_constant())
         {
           temp =
               Statement::make_temporary(NULL, this->right_, loc);
@@ -5601,7 +5594,9 @@ Binary_expression::do_check_types(Gogo*)
       if (left_type->integer_type() == NULL)
 	this->report_error(_("shift of non-integer operand"));
 
-      if (!right_type->is_abstract()
+      if (right_type->is_string_type())
+        this->report_error(_("shift count not unsigned integer"));
+      else if (!right_type->is_abstract()
 	  && (right_type->integer_type() == NULL
 	      || !right_type->integer_type()->is_unsigned()))
 	this->report_error(_("shift count not unsigned integer"));
diff --git a/gcc/go/gofrontend/gogo.cc b/gcc/go/gofrontend/gogo.cc
index 5ecc55d0dbb..363fd5cff18 100644
--- a/gcc/go/gofrontend/gogo.cc
+++ b/gcc/go/gofrontend/gogo.cc
@@ -516,7 +516,6 @@ Gogo::import_package(const std::string& filename,
     {
       Package* package = p->second;
       package->set_location(location);
-      package->set_is_imported();
       std::string ln = local_name;
       bool is_ln_exported = is_local_name_exported;
       if (ln.empty())
@@ -525,7 +524,9 @@ Gogo::import_package(const std::string& filename,
 	  go_assert(!ln.empty());
 	  is_ln_exported = Lex::is_exported_name(ln);
 	}
-      if (ln == ".")
+      if (ln == "_")
+        ;
+      else if (ln == ".")
 	{
 	  Bindings* bindings = package->bindings();
 	  for (Bindings::const_declarations_iterator p =
@@ -533,11 +534,12 @@ Gogo::import_package(const std::string& filename,
 	       p != bindings->end_declarations();
 	       ++p)
 	    this->add_dot_import_object(p->second);
+          std::string dot_alias = "." + package->package_name();
+          package->add_alias(dot_alias, location);
 	}
-      else if (ln == "_")
-	package->set_uses_sink_alias();
       else
 	{
+          package->add_alias(ln, location);
 	  ln = this->pack_hidden_name(ln, is_ln_exported);
 	  this->package_->bindings()->add_package(ln, package);
 	}
@@ -563,7 +565,6 @@ Gogo::import_package(const std::string& filename,
 		  "being compiled (see -fgo-pkgpath option)"));
 
       this->imports_.insert(std::make_pair(filename, package));
-      package->set_is_imported();
     }
 
   delete stream;
@@ -1544,7 +1545,10 @@ Gogo::lookup(const std::string& name, Named_object** pfunction) const
       if (ret != NULL)
 	{
 	  if (ret->package() != NULL)
-	    ret->package()->note_usage();
+            {
+              std::string dot_alias = "." + ret->package()->package_name();
+              ret->package()->note_usage(dot_alias);
+            }
 	  return ret;
 	}
     }
@@ -1594,10 +1598,14 @@ Gogo::add_imported_package(const std::string& real_name,
 
   *padd_to_globals = false;
 
-  if (alias_arg == ".")
-    *padd_to_globals = true;
-  else if (alias_arg == "_")
-    ret->set_uses_sink_alias();
+  if (alias_arg == "_")
+    ;
+  else if (alias_arg == ".")
+    {
+      *padd_to_globals = true;
+      std::string dot_alias = "." + real_name;
+      ret->add_alias(dot_alias, location);
+    }
   else
     {
       std::string alias = alias_arg;
@@ -1606,6 +1614,7 @@ Gogo::add_imported_package(const std::string& real_name,
 	  alias = real_name;
 	  is_alias_exported = Lex::is_exported_name(alias);
 	}
+      ret->add_alias(alias, location);
       alias = this->pack_hidden_name(alias, is_alias_exported);
       Named_object* no = this->package_->bindings()->add_package(alias, ret);
       if (!no->is_package())
@@ -2356,15 +2365,30 @@ Gogo::clear_file_scope()
        ++p)
     {
       Package* package = p->second;
-      if (package != this->package_
-	  && package->is_imported()
-	  && !package->used()
-	  && !package->uses_sink_alias()
-	  && !quiet)
-	error_at(package->location(), "imported and not used: %s",
-		 Gogo::message_name(package->package_name()).c_str());
-      package->clear_is_imported();
-      package->clear_uses_sink_alias();
+      if (package != this->package_ && !quiet)
+        {
+          for (Package::Aliases::const_iterator p1 = package->aliases().begin();
+               p1 != package->aliases().end();
+               ++p1)
+            {
+              if (!p1->second->used())
+                {
+                  // Give a more refined error message if the alias name is known.
+                  std::string pkg_name = package->package_name();
+                  if (p1->first != pkg_name && p1->first[0] != '.')
+                    {
+                      error_at(p1->second->location(),
+                               "imported and not used: %s as %s",
+                               Gogo::message_name(pkg_name).c_str(),
+                               Gogo::message_name(p1->first).c_str());
+                    }
+                  else
+                    error_at(p1->second->location(),
+                             "imported and not used: %s",
+                             Gogo::message_name(pkg_name).c_str());
+                }
+            }
+        }
       package->clear_used();
     }
 }
@@ -7741,8 +7765,7 @@ Package::Package(const std::string& pkgpath,
 		 const std::string& pkgpath_symbol, Location location)
   : pkgpath_(pkgpath), pkgpath_symbol_(pkgpath_symbol),
     package_name_(), bindings_(new Bindings(NULL)), priority_(0),
-    location_(location), used_(false), is_imported_(false),
-    uses_sink_alias_(false)
+    location_(location)
 {
   go_assert(!pkgpath.empty());
   
@@ -7796,6 +7819,16 @@ Package::set_priority(int priority)
     this->priority_ = priority;
 }
 
+// Note that symbol from this package was and qualified by ALIAS.
+
+void
+Package::note_usage(const std::string& alias) const
+{
+  Aliases::const_iterator p = this->aliases_.find(alias);
+  go_assert(p != this->aliases_.end());
+  p->second->note_usage();
+}
+
 // Forget a given usage.  If forgetting this usage means this package becomes
 // unused, report that error.
 
@@ -7811,7 +7844,7 @@ Package::forget_usage(Expression* usage) const
 
   if (this->fake_uses_.empty())
     error_at(this->location(), "imported and not used: %s",
-	     Gogo::message_name(this->package_name()).c_str());
+             Gogo::message_name(this->package_name()).c_str());
 }
 
 // Clear the used field for the next file.  If the only usages of this package
@@ -7820,10 +7853,26 @@ Package::forget_usage(Expression* usage) const
 void
 Package::clear_used()
 {
-  if (this->used_ > this->fake_uses_.size())
+  std::string dot_alias = "." + this->package_name();
+  Aliases::const_iterator p = this->aliases_.find(dot_alias);
+  if (p != this->aliases_.end() && p->second->used() > this->fake_uses_.size())
     this->fake_uses_.clear();
 
-  this->used_ = 0;
+  this->aliases_.clear();
+}
+
+Package_alias*
+Package::add_alias(const std::string& alias, Location location)
+{
+  Aliases::const_iterator p = this->aliases_.find(alias);
+  if (p == this->aliases_.end())
+    {
+      std::pair<Aliases::iterator, bool> ret;
+      ret = this->aliases_.insert(std::make_pair(alias,
+                                                 new Package_alias(location)));
+      p = ret.first;
+    }
+  return p->second;
 }
 
 // Determine types of constants.  Everything else in a package
diff --git a/gcc/go/gofrontend/gogo.h b/gcc/go/gofrontend/gogo.h
index 3af2af745fb..6333c834c35 100644
--- a/gcc/go/gofrontend/gogo.h
+++ b/gcc/go/gofrontend/gogo.h
@@ -2771,6 +2771,37 @@ class Unnamed_label
   Blabel* blabel_;
 };
 
+// An alias for an imported package.
+
+class Package_alias
+{
+ public:
+  Package_alias(Location location)
+      : location_(location), used_(0)
+  { }
+
+  // The location of the import statement.
+  Location
+  location()
+  { return this->location_; }
+
+  // How many symbols from the package were used under this alias.
+  size_t
+  used() const
+  { return this->used_; }
+
+  // Note that some symbol was used under this alias.
+  void
+  note_usage()
+  { this->used_++; }
+
+ private:
+  // The location of the import statement.
+  Location location_;
+  // The amount of times some name from this package was used under this alias.
+  size_t used_;
+};
+
 // An imported package.
 
 class Package
@@ -2793,7 +2824,7 @@ class Package
   void
   set_pkgpath_symbol(const std::string&);
 
-  // Return the location of the import statement.
+  // Return the location of the most recent import statement.
   Location
   location() const
   { return this->location_; }
@@ -2829,15 +2860,18 @@ class Package
   bindings()
   { return this->bindings_; }
 
-  // Whether some symbol from the package was used.
-  bool
-  used() const
-  { return this->used_ > 0; }
+  // Type used to map import names to package aliases.
+  typedef std::map<std::string, Package_alias*> Aliases;
 
-  // Note that some symbol from this package was used.
+  // Return the set of package aliases.
+  const Aliases&
+  aliases() const
+  { return this->aliases_; }
+
+  // Note that some symbol from this package was used and qualified by ALIAS.
+  // For dot imports, the ALIAS should be ".PACKAGE_NAME".
   void
-  note_usage() const
-  { this->used_++; }
+  note_usage(const std::string& alias) const;
 
   // Note that USAGE might be a fake usage of this package.
   void
@@ -2852,36 +2886,6 @@ class Package
   void
   clear_used();
 
-  // Whether this package was imported in the current file.
-  bool
-  is_imported() const
-  { return this->is_imported_; }
-
-  // Note that this package was imported in the current file.
-  void
-  set_is_imported()
-  { this->is_imported_ = true; }
-
-  // Clear the imported field for the next file.
-  void
-  clear_is_imported()
-  { this->is_imported_ = false; }
-
-  // Whether this package was imported with a name of "_".
-  bool
-  uses_sink_alias() const
-  { return this->uses_sink_alias_; }
-
-  // Note that this package was imported with a name of "_".
-  void
-  set_uses_sink_alias()
-  { this->uses_sink_alias_ = true; }
-
-  // Clear the sink alias field for the next file.
-  void
-  clear_uses_sink_alias()
-  { this->uses_sink_alias_ = false; }
-
   // Look up a name in the package.  Returns NULL if the name is not
   // found.
   Named_object*
@@ -2898,6 +2902,10 @@ class Package
   set_location(Location location)
   { this->location_ = location; }
 
+  // Add a package name as an ALIAS for this package.
+  Package_alias*
+  add_alias(const std::string& alias, Location);
+
   // Add a constant to the package.
   Named_object*
   add_constant(const Typed_identifier& tid, Expression* expr)
@@ -2942,18 +2950,13 @@ class Package
   // than the priority of all of the packages that it imports.  This
   // is used to run init functions in the right order.
   int priority_;
-  // The location of the import statement.
+  // The location of the most recent import statement.
   Location location_;
-  // The amount of times some name from this package was used.  This is mutable
-  // because we can use a package even if we have a const pointer to it.
-  mutable size_t used_;
-  // A set of possibly fake uses of this package.  This is mutable because we
+  // The set of aliases associated with this package.
+  Aliases aliases_;
+  // A set of possibly fake uses of this package. This is mutable because we
   // can track fake uses of a package even if we have a const pointer to it.
   mutable std::set<Expression*> fake_uses_;
-  // True if this package was imported in the current file.
-  bool is_imported_;
-  // True if this package was imported with a name of "_".
-  bool uses_sink_alias_;
 };
 
 // Return codes for the traversal functions.  This is not an enum
diff --git a/gcc/go/gofrontend/lex.cc b/gcc/go/gofrontend/lex.cc
index 98d98da74ec..30167e581ac 100644
--- a/gcc/go/gofrontend/lex.cc
+++ b/gcc/go/gofrontend/lex.cc
@@ -1882,7 +1882,7 @@ static const Unicode_range unicode_letters[] =
   { 0x081a, 0x0824, 10},
   { 0x0828, 0x0840, 24},
   { 0x0841, 0x0858, 1},
-  { 0x08a0, 0x08b2, 1},
+  { 0x08a0, 0x08b4, 1},
   { 0x0904, 0x0939, 1},
   { 0x093d, 0x0950, 19},
   { 0x0958, 0x0961, 1},
@@ -1915,7 +1915,8 @@ static const Unicode_range unicode_letters[] =
   { 0x0ab5, 0x0ab9, 1},
   { 0x0abd, 0x0ad0, 19},
   { 0x0ae0, 0x0ae1, 1},
-  { 0x0b05, 0x0b0c, 1},
+  { 0x0af9, 0x0b05, 12},
+  { 0x0b06, 0x0b0c, 1},
   { 0x0b0f, 0x0b10, 1},
   { 0x0b13, 0x0b28, 1},
   { 0x0b2a, 0x0b30, 1},
@@ -1940,9 +1941,9 @@ static const Unicode_range unicode_letters[] =
   { 0x0c12, 0x0c28, 1},
   { 0x0c2a, 0x0c39, 1},
   { 0x0c3d, 0x0c58, 27},
-  { 0x0c59, 0x0c60, 7},
-  { 0x0c61, 0x0c85, 36},
-  { 0x0c86, 0x0c8c, 1},
+  { 0x0c59, 0x0c5a, 1},
+  { 0x0c60, 0x0c61, 1},
+  { 0x0c85, 0x0c8c, 1},
   { 0x0c8e, 0x0c90, 1},
   { 0x0c92, 0x0ca8, 1},
   { 0x0caa, 0x0cb3, 1},
@@ -1953,7 +1954,7 @@ static const Unicode_range unicode_letters[] =
   { 0x0d05, 0x0d0c, 1},
   { 0x0d0e, 0x0d10, 1},
   { 0x0d12, 0x0d3a, 1},
-  { 0x0d3d, 0x0d4e, 17},
+  { 0x0d3d, 0x0d5f, 17},
   { 0x0d60, 0x0d61, 1},
   { 0x0d7a, 0x0d7f, 1},
   { 0x0d85, 0x0d96, 1},
@@ -2012,7 +2013,8 @@ static const Unicode_range unicode_letters[] =
   { 0x1312, 0x1315, 1},
   { 0x1318, 0x135a, 1},
   { 0x1380, 0x138f, 1},
-  { 0x13a0, 0x13f4, 1},
+  { 0x13a0, 0x13f5, 1},
+  { 0x13f8, 0x13fd, 1},
   { 0x1401, 0x166c, 1},
   { 0x166f, 0x167f, 1},
   { 0x1681, 0x169a, 1},
@@ -2034,7 +2036,7 @@ static const Unicode_range unicode_letters[] =
   { 0x1950, 0x196d, 1},
   { 0x1970, 0x1974, 1},
   { 0x1980, 0x19ab, 1},
-  { 0x19c1, 0x19c7, 1},
+  { 0x19b0, 0x19c9, 1},
   { 0x1a00, 0x1a16, 1},
   { 0x1a20, 0x1a54, 1},
   { 0x1aa7, 0x1b05, 94},
@@ -2111,7 +2113,7 @@ static const Unicode_range unicode_letters[] =
   { 0x31a0, 0x31ba, 1},
   { 0x31f0, 0x31ff, 1},
   { 0x3400, 0x4db5, 1},
-  { 0x4e00, 0x9fcc, 1},
+  { 0x4e00, 0x9fd5, 1},
   { 0xa000, 0xa48c, 1},
   { 0xa4d0, 0xa4fd, 1},
   { 0xa500, 0xa60c, 1},
@@ -2122,9 +2124,8 @@ static const Unicode_range unicode_letters[] =
   { 0xa6a0, 0xa6e5, 1},
   { 0xa717, 0xa71f, 1},
   { 0xa722, 0xa788, 1},
-  { 0xa78b, 0xa78e, 1},
-  { 0xa790, 0xa7ad, 1},
-  { 0xa7b0, 0xa7b1, 1},
+  { 0xa78b, 0xa7ad, 1},
+  { 0xa7b0, 0xa7b7, 1},
   { 0xa7f7, 0xa801, 1},
   { 0xa803, 0xa805, 1},
   { 0xa807, 0xa80a, 1},
@@ -2132,8 +2133,8 @@ static const Unicode_range unicode_letters[] =
   { 0xa840, 0xa873, 1},
   { 0xa882, 0xa8b3, 1},
   { 0xa8f2, 0xa8f7, 1},
-  { 0xa8fb, 0xa90a, 15},
-  { 0xa90b, 0xa925, 1},
+  { 0xa8fb, 0xa8fd, 2},
+  { 0xa90a, 0xa925, 1},
   { 0xa930, 0xa946, 1},
   { 0xa960, 0xa97c, 1},
   { 0xa984, 0xa9b2, 1},
@@ -2160,9 +2161,8 @@ static const Unicode_range unicode_letters[] =
   { 0xab20, 0xab26, 1},
   { 0xab28, 0xab2e, 1},
   { 0xab30, 0xab5a, 1},
-  { 0xab5c, 0xab5f, 1},
-  { 0xab64, 0xab65, 1},
-  { 0xabc0, 0xabe2, 1},
+  { 0xab5c, 0xab65, 1},
+  { 0xab70, 0xabe2, 1},
   { 0xac00, 0xd7a3, 1},
   { 0xd7b0, 0xd7c6, 1},
   { 0xd7cb, 0xd7fb, 1},
@@ -2221,6 +2221,8 @@ static const Unicode_range unicode_letters[] =
   { 0x10840, 0x10855, 1},
   { 0x10860, 0x10876, 1},
   { 0x10880, 0x1089e, 1},
+  { 0x108e0, 0x108f2, 1},
+  { 0x108f4, 0x108f5, 1},
   { 0x10900, 0x10915, 1},
   { 0x10920, 0x10939, 1},
   { 0x10980, 0x109b7, 1},
@@ -2238,6 +2240,8 @@ static const Unicode_range unicode_letters[] =
   { 0x10b60, 0x10b72, 1},
   { 0x10b80, 0x10b91, 1},
   { 0x10c00, 0x10c48, 1},
+  { 0x10c80, 0x10cb2, 1},
+  { 0x10cc0, 0x10cf2, 1},
   { 0x11003, 0x11037, 1},
   { 0x11083, 0x110af, 1},
   { 0x110d0, 0x110e8, 1},
@@ -2246,9 +2250,14 @@ static const Unicode_range unicode_letters[] =
   { 0x11176, 0x11183, 13},
   { 0x11184, 0x111b2, 1},
   { 0x111c1, 0x111c4, 1},
-  { 0x111da, 0x11200, 38},
-  { 0x11201, 0x11211, 1},
+  { 0x111da, 0x111dc, 2},
+  { 0x11200, 0x11211, 1},
   { 0x11213, 0x1122b, 1},
+  { 0x11280, 0x11286, 1},
+  { 0x11288, 0x1128a, 2},
+  { 0x1128b, 0x1128d, 1},
+  { 0x1128f, 0x1129d, 1},
+  { 0x1129f, 0x112a8, 1},
   { 0x112b0, 0x112de, 1},
   { 0x11305, 0x1130c, 1},
   { 0x1130f, 0x11310, 1},
@@ -2256,20 +2265,24 @@ static const Unicode_range unicode_letters[] =
   { 0x1132a, 0x11330, 1},
   { 0x11332, 0x11333, 1},
   { 0x11335, 0x11339, 1},
-  { 0x1133d, 0x1135d, 32},
-  { 0x1135e, 0x11361, 1},
+  { 0x1133d, 0x11350, 19},
+  { 0x1135d, 0x11361, 1},
   { 0x11480, 0x114af, 1},
   { 0x114c4, 0x114c5, 1},
   { 0x114c7, 0x11580, 185},
   { 0x11581, 0x115ae, 1},
+  { 0x115d8, 0x115db, 1},
   { 0x11600, 0x1162f, 1},
   { 0x11644, 0x11680, 60},
   { 0x11681, 0x116aa, 1},
+  { 0x11700, 0x11719, 1},
   { 0x118a0, 0x118df, 1},
   { 0x118ff, 0x11ac0, 449},
   { 0x11ac1, 0x11af8, 1},
-  { 0x12000, 0x12398, 1},
+  { 0x12000, 0x12399, 1},
+  { 0x12480, 0x12543, 1},
   { 0x13000, 0x1342e, 1},
+  { 0x14400, 0x14646, 1},
   { 0x16800, 0x16a38, 1},
   { 0x16a40, 0x16a5e, 1},
   { 0x16ad0, 0x16aed, 1},
@@ -2343,6 +2356,7 @@ static const Unicode_range unicode_letters[] =
   { 0x20000, 0x2a6d6, 1},
   { 0x2a700, 0x2b734, 1},
   { 0x2b740, 0x2b81d, 1},
+  { 0x2b820, 0x2cea1, 1},
   { 0x2f800, 0x2fa1d, 1},
 };
 
diff --git a/gcc/go/gofrontend/parse.cc b/gcc/go/gofrontend/parse.cc
index cc4377627e9..9d6a8c6f4a6 100644
--- a/gcc/go/gofrontend/parse.cc
+++ b/gcc/go/gofrontend/parse.cc
@@ -198,7 +198,7 @@ Parse::qualified_ident(std::string* pname, Named_object** ppackage)
       return false;
     }
 
-  package->package_value()->note_usage();
+  package->package_value()->note_usage(Gogo::unpack_hidden_name(name));
 
   token = this->advance_token();
   if (!token->is_identifier())
@@ -2430,7 +2430,7 @@ Parse::operand(bool may_be_sink, bool* is_parenthesized)
 		return Expression::make_error(location);
 	      }
 	    package = named_object->package_value();
-	    package->note_usage();
+	    package->note_usage(id);
 	    id = this->peek_token()->identifier();
 	    is_exported = this->peek_token()->is_identifier_exported();
 	    packed = this->gogo_->pack_hidden_name(id, is_exported);
diff --git a/gcc/go/gofrontend/unsafe.cc b/gcc/go/gofrontend/unsafe.cc
index ca9622569bd..9ed5b9d0d3c 100644
--- a/gcc/go/gofrontend/unsafe.cc
+++ b/gcc/go/gofrontend/unsafe.cc
@@ -32,8 +32,6 @@ Gogo::import_unsafe(const std::string& local_name, bool is_local_name_exported,
     }
 
   package->set_location(location);
-  package->set_is_imported();
-
   this->imports_.insert(std::make_pair("unsafe", package));
 
   Bindings* bindings = package->bindings();
diff --git a/gcc/go/gospec.c b/gcc/go/gospec.c
index ca3c2d70d68..a56ffe0fad1 100644
--- a/gcc/go/gospec.c
+++ b/gcc/go/gospec.c
@@ -120,8 +120,10 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
   /* Whether the -S option was used.  */
   bool saw_opt_S = false;
 
-  /* Whether the -m32 option was used. */
-  bool saw_opt_m32 ATTRIBUTE_UNUSED = false;
+#ifdef TARGET_CAN_SPLIT_STACK_64BIT
+  /* Whether the -m64 option is in force. */
+  bool is_m64 = TARGET_CAN_SPLIT_STACK_64BIT;
+#endif
 
   /* The first input file with an extension of .go.  */
   const char *first_go_file = NULL;  
@@ -160,7 +162,11 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
 
 #ifdef TARGET_CAN_SPLIT_STACK_64BIT
 	case OPT_m32:
-	  saw_opt_m32 = true;
+	  is_m64 = false;
+	  break;
+
+	case OPT_m64:
+	  is_m64 = true;
 	  break;
 #endif
 
@@ -253,7 +259,7 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
 #endif
 
 #ifdef TARGET_CAN_SPLIT_STACK_64BIT
-  if (!saw_opt_m32)
+  if (is_m64)
     supports_split_stack = 1;
 #endif
 
diff --git a/gcc/go/lang.opt b/gcc/go/lang.opt
index 4b1c671b323..3b304eac7bc 100644
--- a/gcc/go/lang.opt
+++ b/gcc/go/lang.opt
@@ -39,35 +39,35 @@ Go
 
 fgo-check-divide-zero
 Go Var(go_check_divide_zero) Init(1)
-Add explicit checks for division by zero
+Add explicit checks for division by zero.
 
 fgo-check-divide-overflow
 Go Var(go_check_divide_overflow) Init(1)
-Add explicit checks for division overflow in INT_MIN / -1
+Add explicit checks for division overflow in INT_MIN / -1.
 
 fgo-dump-
 Go Joined RejectNegative
--fgo-dump-<type>	Dump Go frontend internal information
+-fgo-dump-<type>	Dump Go frontend internal information.
 
 fgo-optimize-
 Go Joined RejectNegative
--fgo-optimize-<type>	Turn on optimization passes in the frontend
+-fgo-optimize-<type>	Turn on optimization passes in the frontend.
 
 fgo-pkgpath=
 Go Joined RejectNegative
--fgo-pkgpath=<string>	Set Go package path
+-fgo-pkgpath=<string>	Set Go package path.
 
 fgo-prefix=
 Go Joined RejectNegative
--fgo-prefix=<string>	Set package-specific prefix for exported Go names
+-fgo-prefix=<string>	Set package-specific prefix for exported Go names.
 
 fgo-relative-import-path=
 Go Joined RejectNegative
--fgo-relative-import-path=<path> Treat a relative import as relative to path
+-fgo-relative-import-path=<path> Treat a relative import as relative to path.
 
 frequire-return-statement
 Go Var(go_require_return_statement) Init(1) Warning
-Functions which return values must end with return statements
+Functions which return values must end with return statements.
 
 o
 Go Joined Separate