gcc: Bring updates from Google's enhanced gcc-4.2.1.

Google released and enhanced version of gcc-4.2.1 plus their local
patches for Android[1].

The patches are owned by Google and the license hasn't been changed
from  the original GPLv2. We are only bringing a subset of the
available patches that may be helpful in FreeBSD. Changes specific
to android are not included.

From the README.google file[1].

Patches applied to google_vendor_src_branch/gcc/gcc-4.2.1:

gcc/Makefile.in
gcc/c-common.c
gcc/c-common.h
gcc/c-opts.c
gcc/c-typeck.c
gcc/cp/typeck.c
gcc/doc/invoke.texi
gcc/flags.h
gcc/opts.c
gcc/tree-flow.h
gcc/tree-ssa-alias-warnings.c
gcc/tree-ssa-alias.c

 Backport of -Wstrict-aliasing from mainline.
  Silvius Rus <rus@google.com>

gcc/coverage.c:
  Patch coverage_checksum_string for PR 25351.
  Seongbae Park <spark@google.com>
  Not yet submitted to FSF.

gcc/c-opts.c
gcc/c-ppoutput.c
gcc/c.opt
gcc/doc/cppopts.texi
libcpp/Makefile.in
libcpp/directives-only.c
libcpp/directives.c
libcpp/files.c
libcpp/include/cpplib.h
libcpp/init.c
libcpp/internal.h
libcpp/macro.c
  Support for -fdirectives-only.
  Ollie Wild <aaw@google.com>.
  Submitted to FSF but not yet approved.

libstdc++-v3/include/ext/hashtable.h
  http://b/742065
  http://b/629994
  Reduce min size of hashtable for hash_map, hash_set from 53 to 5

libstdc++-v3/include/ext/hashtable.h
  http://b/629994
  Do not iterate over buckets if hashtable is empty.

gcc/common.opt
gcc/doc/invoke.texi
gcc/flags.h
gcc/gimplify.c
gcc/opts.c
  Add Saito's patch for -finstrument-functions-exclude-* options.

gcc/common.opt
gcc/doc/invoke.texi
gcc/final.c
gcc/flags.h
gcc/opts.c
gcc/testsuite/gcc.dg/Wframe-larger-than.c
  Add a new flag -Wframe-larger-than- which enables a new warning
  when a frame size of a function is larger than specified.
  This patch hasn't been integrated into gcc mainline yet.

gcc/tree-vrp.c
  Add a hack to avoid using ivopts information for pointers starting
  at constant values.

Reference:

[1]
https://android.googlesource.com/toolchain/gcc/+/master/gcc-4.2.1/

Obtained from:	Google Inc.
MFC after:	3 weeks

1 files changed, 20 insertions, 1 deletions

diff --git a/contrib/gcc/c-opts.c b/contrib/gcc/c-opts.c
index 7f193749fd6a..0c584eb8ca74 100644
--- a/contrib/gcc/c-opts.c
+++ b/contrib/gcc/c-opts.c
@@ -396,7 +396,7 @@ c_common_handle_option (size_t scode, const char *arg, int value)
       if (c_dialect_cxx ())
 	warn_sign_compare = value;
       warn_switch = value;
-      warn_strict_aliasing = value;
+      set_warn_strict_aliasing (value);
       warn_strict_overflow = value;
       warn_address = value;
 
@@ -606,6 +606,10 @@ c_common_handle_option (size_t scode, const char *arg, int value)
 	disable_builtin_function (arg);
       break;
 
+    case OPT_fdirectives_only:
+      cpp_opts->directives_only = 1;
+      break;
+
     case OPT_fdollars_in_identifiers:
       cpp_opts->dollars_in_ident = value;
       break;
@@ -1329,6 +1333,11 @@ sanitize_cpp_opts (void)
   if (flag_dump_macros == 'M')
     flag_no_output = 1;
 
+  /* By default, -fdirectives-only implies -dD.  This allows subsequent phases
+     to perform proper macro expansion.  */
+  if (cpp_opts->directives_only && !cpp_opts->preprocessed && !flag_dump_macros)
+    flag_dump_macros = 'D';
+
   /* Disable -dD, -dN and -dI if normal output is suppressed.  Allow
      -dM since at least glibc relies on -M -dM to work.  */
   /* Also, flag_no_output implies flag_no_line_commands, always.  */
@@ -1359,6 +1368,14 @@ sanitize_cpp_opts (void)
      actually output the current directory?  */
   if (flag_working_directory == -1)
     flag_working_directory = (debug_info_level != DINFO_LEVEL_NONE);
+
+  if (cpp_opts->directives_only)
+    {
+      if (warn_unused_macros)
+	error ("-fdirectives-only is incompatible with -Wunused_macros");
+      if (cpp_opts->traditional)
+	error ("-fdirectives-only is incompatible with -traditional");
+    }
 }
 
 /* Add include path with a prefix at the front of its name.  */
@@ -1442,6 +1459,8 @@ finish_options (void)
 	    }
 	}
     }
+  else if (cpp_opts->directives_only)
+    cpp_init_special_builtins (parse_in);
 
   include_cursor = 0;
   push_command_line_include ();