(1) Record relevant GCC command line options in the gcda file (-O*, -f*,

    -W*, --param).
(2) At profile-use time, if foo.cc imports bar.cc, compare the command line
    options that were used at profile-generate time for these two modules
    (these options are recorded in the gcda file), and decide if bar.cc
    would be compatible with foo.cc.
(3) New warning option -Wripa-opt-mismatch emits a warning whenever we
    encounter auxiliary modules with mismatching options from the primary
    module (this warning is turned on by -Wall).
(4) New option -fripa-disallow-opt-mismatch skips auxiliary modules with
    mismatching options from the primary module.



git-svn-id: https://gcc.gnu.org/svn/gcc/branches/lw-ipo@150867 138bc75d-0d04-0410-961f-82ee72b054a4

9 files changed, 225 insertions, 44 deletions

diff --git a/gcc/c-opts.c b/gcc/c-opts.c
index b1343fef53e..1859534c9b3 100644
--- a/gcc/c-opts.c
+++ b/gcc/c-opts.c
@@ -388,6 +388,7 @@ c_common_handle_option (size_t scode, const char *arg, int value)
       warn_missing_braces = value;
       warn_parentheses = value;
       warn_return_type = value;
+      warn_ripa_opt_mismatch = value;
       warn_sequence_point = value;	/* Was C only.  */
       warn_switch = value;
       if (warn_strict_aliasing == -1)
diff --git a/gcc/common.opt b/gcc/common.opt
index d0ecea8a1aa..947eeb7b8ef 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -152,6 +152,10 @@ Wpadded
 Common Var(warn_padded) Warning
 Warn when padding is required to align structure members
 
+Wripa-opt-mismatch
+Common Var(warn_ripa_opt_mismatch) Warning
+Warn if primary and auxiliary modules have mismatched command line options
+
 Wshadow
 Common Var(warn_shadow) Warning
 Warn when one local variable shadows another
@@ -482,6 +486,10 @@ fdump-unnumbered-links
 Common Report Var(flag_dump_unnumbered_links) VarExists
 Suppress output of previous and next insn numbers in debugging dumps
 
+fripa-disallow-opt-mismatch
+Common Report Var(flag_ripa_disallow_opt_mismatch)
+Don't import an auxiliary module if the command line options mismatch with the primary module
+
 fearly-inlining
 Common Report Var(flag_early_inlining) Init(1) Optimization
 Perform early inlining
diff --git a/gcc/coverage.c b/gcc/coverage.c
index 914e48691f4..4d22ca8d3a3 100644
--- a/gcc/coverage.c
+++ b/gcc/coverage.c
@@ -149,7 +149,7 @@ static tree build_ctr_info_type (void);
 static tree build_ctr_info_value (unsigned, tree);
 static tree build_gcov_info (void);
 static void create_coverage (void);
-static void get_da_file_name (const char *);
+static char * get_da_file_name (const char *);
 
 /* Return the type node for gcov_type.  */
 
@@ -205,6 +205,70 @@ is_last_module (unsigned mod_id)
   return (mod_id == module_infos[num_in_fnames - 1]->ident);
 }
 
+/* Returns true if the command-line arguments stored in the given module-infos
+   are incompatible.  */
+static bool
+incompatible_cl_args (struct gcov_module_info* mod_info1,
+		      struct gcov_module_info* mod_info2)
+{
+  char **warning_opts1 = XNEWVEC (char *, mod_info1->num_cl_args);
+  char **warning_opts2 = XNEWVEC (char *, mod_info2->num_cl_args);
+  char **non_warning_opts1 = XNEWVEC (char *, mod_info1->num_cl_args);
+  char **non_warning_opts2 = XNEWVEC (char *, mod_info2->num_cl_args);
+  unsigned int i, num_warning_opts1 = 0, num_warning_opts2 = 0;
+  unsigned int num_non_warning_opts1 = 0, num_non_warning_opts2 = 0;
+  bool warning_mismatch = false;
+  bool non_warning_mismatch = false;
+  unsigned int start_index1 = mod_info1->num_quote_paths +
+    mod_info1->num_bracket_paths + mod_info1->num_cpp_defines;
+  unsigned int start_index2 = mod_info2->num_quote_paths +
+    mod_info2->num_bracket_paths + mod_info2->num_cpp_defines;
+
+  /* First, separate the warning and non-warning options.  */
+  for (i = 0; i < mod_info1->num_cl_args; i++)
+    if (mod_info1->string_array[start_index1 + i][1] == 'W')
+      warning_opts1[num_warning_opts1++] =
+	mod_info1->string_array[start_index1 + i];
+    else
+      non_warning_opts1[num_non_warning_opts1++] =
+	mod_info1->string_array[start_index1 + i];
+
+  for (i = 0; i < mod_info2->num_cl_args; i++)
+    if (mod_info2->string_array[start_index2 + i][1] == 'W')
+      warning_opts2[num_warning_opts2++] =
+	mod_info2->string_array[start_index2 + i];
+    else
+      non_warning_opts2[num_non_warning_opts2++] =
+	mod_info2->string_array[start_index2 + i];
+
+  /* Compare warning options. If these mismatch, we emit a warning.  */
+  if (num_warning_opts1 != num_warning_opts2)
+    warning_mismatch = true;
+  else
+    for (i = 0; i < num_warning_opts1 && !warning_mismatch; i++)
+      warning_mismatch = strcmp (warning_opts1[i], warning_opts2[i]) != 0;
+
+  /* Compare non-warning options. If these mismatch, we emit a warning, and if
+     -fripa-disallow-opt-mismatch is supplied, the two modules are also
+     incompatible.  */
+  if (num_non_warning_opts1 != num_non_warning_opts2)
+    non_warning_mismatch = true;
+  else
+    for (i = 0; i < num_non_warning_opts1 && !non_warning_mismatch; i++)
+      non_warning_mismatch =
+	strcmp (non_warning_opts1[i], non_warning_opts2[i]) != 0;
+
+  if (warn_ripa_opt_mismatch && (warning_mismatch || non_warning_mismatch))
+    warning (OPT_Wripa_opt_mismatch, "command line arguments mismatch for %s "
+	     "and %s", mod_info1->source_filename, mod_info2->source_filename);
+
+  XDELETEVEC (warning_opts1);
+  XDELETEVEC (warning_opts2);
+  XDELETEVEC (non_warning_opts1);
+  XDELETEVEC (non_warning_opts2);
+  return flag_ripa_disallow_opt_mismatch && non_warning_mismatch;
+}
+
 /* Read in the counts file, if available. DA_FILE_NAME is the
    name of the gcda file, and MODULE_ID is the module id of the
    associated source module.  */
@@ -377,16 +441,16 @@ read_counts_file (const char *da_file_name, unsigned module_id)
               = (struct gcov_module_info *) alloca ((length + 2)
                                                     * sizeof (gcov_unsigned_t));
 	  gcov_read_module_info (mod_info, length);
-	  module_infos_read++;
-
           info_sz = (sizeof (struct gcov_module_info) +
 		     sizeof (void *) * (mod_info->num_quote_paths +
 					mod_info->num_bracket_paths +
-					mod_info->num_cpp_defines));
+					mod_info->num_cpp_defines +
+					mod_info->num_cl_args));
 	  /* The first MODULE_INFO record must be for the primary module.  */
-	  if (module_infos_read == 1)
+	  if (module_infos_read == 0)
 	    {
 	      gcc_assert (mod_info->is_primary && !modset);
+	      module_infos_read++;
               modset = pointer_set_create ();
               pointer_set_insert (modset, (void *)(size_t)mod_info->ident);
 	      primary_module_id = mod_info->ident;
@@ -396,33 +460,49 @@ read_counts_file (const char *da_file_name, unsigned module_id)
 	    }
 	  else
             {
+	      int fd;
+	      char *aux_da_filename = get_da_file_name (mod_info->da_filename);
               gcc_assert (!mod_info->is_primary);
-              if (!pointer_set_insert (modset, (void *)(size_t)mod_info->ident)
-                  /* Forbid mixed language LIPO for now.  */
-                  && module_infos[0]->lang == mod_info->lang
-                  /* Debugging support.  */
-                  && module_infos_read <= max_group)
+	      if (pointer_set_insert (modset, (void *)(size_t)mod_info->ident))
+		inform (input_location, "Not importing %s: already imported",
+			mod_info->source_filename);
+	      else if (module_infos[0]->lang != mod_info->lang)
+		inform (input_location, "Not importing %s: source language"
+			" different from primary module's source language",
+			mod_info->source_filename);
+	      else if (module_infos_read == max_group)
+		inform (input_location, "Not importing %s: maximum group size"
+			" reached", mod_info->source_filename);
+	      else if (incompatible_cl_args (module_infos[0], mod_info))
+		inform (input_location, "Not importing %s: command-line"
+			" arguments not compatible with primary module",
+			mod_info->source_filename);
+	      else if ((fd = open (aux_da_filename, O_RDONLY)) < 0)
+		inform (input_location, "Not importing %s: couldn't open %s",
+			mod_info->source_filename, aux_da_filename);
+	      else
 		{
+		  close (fd);
+		  module_infos_read++;
 		  add_input_filename (mod_info->source_filename);
-                  module_infos = XRESIZEVEC (struct gcov_module_info *, module_infos,
-                                             num_in_fnames);
-                  gcc_assert (num_in_fnames == module_infos_read);
-                  module_infos[module_infos_read - 1]
-                      = XCNEWVAR (struct gcov_module_info, info_sz);
-                  memcpy (module_infos[module_infos_read - 1], mod_info, info_sz);
+		  module_infos = XRESIZEVEC (struct gcov_module_info *,
+					     module_infos, num_in_fnames);
+		  gcc_assert (num_in_fnames == module_infos_read);
+		  module_infos[module_infos_read - 1]
+		    = XCNEWVAR (struct gcov_module_info, info_sz);
+		  memcpy (module_infos[module_infos_read - 1], mod_info,
+			  info_sz);
 		}
-              else
-                module_infos_read--;
             }
 
 	  /* Debugging */
           {
-            fprintf (stderr,
-                     "MODULE Id=%d, Is_Primary=%s,"
-                     " Is_Exported=%s, Name=%s (%s)\n",
-                     mod_info->ident, mod_info->is_primary?"yes":"no",
-                     mod_info->is_exported?"yes":"no", mod_info->source_filename,
-                     mod_info->da_filename);
+            inform (input_location,
+		    "MODULE Id=%d, Is_Primary=%s,"
+		    " Is_Exported=%s, Name=%s (%s)",
+		    mod_info->ident, mod_info->is_primary?"yes":"no",
+		    mod_info->is_exported?"yes":"no", mod_info->source_filename,
+		    mod_info->da_filename);
           }
         }
       gcov_sync (offset, length);
@@ -1129,6 +1209,29 @@ build_cpp_def_array_value (tree string_type, tree cpp_def_value,
   return cpp_def_value;
 }
 
+/* Returns an array (tree) of command-line argument strings. STRING_TYPE is
+   the string type, CL_ARGS_VALUE is the initial value of the command-line
+   args array. */
+
+static tree
+build_cl_args_array_value (tree string_type, tree cl_args_value)
+{
+  unsigned int i;
+  for (i = 0; i < num_lipo_cl_args; i++)
+    {
+      int arg_length = strlen (lipo_cl_args[i]);
+      tree arg_string = build_string (arg_length + 1, lipo_cl_args[i]);
+      TREE_TYPE (arg_string) =
+	build_array_type (char_type_node,
+			  build_index_type (build_int_cst (NULL_TREE,
+							   arg_length)));
+      cl_args_value = tree_cons (NULL_TREE,
+				 build1 (ADDR_EXPR, string_type, arg_string),
+				 cl_args_value);
+    }
+  return cl_args_value;
+}
+
 /* Returns the value of the module info associated with the
    current source module being compiled.  */
 
@@ -1254,11 +1357,20 @@ build_gcov_module_info_value (void)
   value = tree_cons (field, build_int_cstu (get_gcov_unsigned_t (),
                                             num_cpp_defines), value);
 
+  /* Num command-line args.  */
+  field = build_decl (UNKNOWN_LOCATION, FIELD_DECL,
+		      NULL_TREE, get_gcov_unsigned_t ());
+  TREE_CHAIN (field) = fields;
+  fields = field;
+  value = tree_cons (field, build_int_cstu (get_gcov_unsigned_t (),
+                                            num_lipo_cl_args), value);
+
   /* string array  */
   index_type = build_index_type (build_int_cst (NULL_TREE,
 						num_quote_paths	+
 						num_bracket_paths +
-						num_cpp_defines));
+						num_cpp_defines +
+						num_lipo_cl_args));
   string_array_type = build_array_type (string_type, index_type);
   string_array = build_inc_path_array_value (string_type, string_array,
 					     quote_paths, num_quote_paths);
@@ -1266,6 +1378,7 @@ build_gcov_module_info_value (void)
 					     bracket_paths, num_bracket_paths);
   string_array = build_cpp_def_array_value (string_type, string_array,
 					    cpp_defines_head);
+  string_array = build_cl_args_array_value (string_type, string_array);
   string_array = build_constructor_from_list (string_array_type,
 					      nreverse (string_array));
   field = build_decl (UNKNOWN_LOCATION, FIELD_DECL,
@@ -1500,9 +1613,10 @@ create_coverage (void)
 
 /* Get the da file name, given base file name.  */
 
-void
+static char *
 get_da_file_name (const char *base_file_name)
 {
+  char *da_file_name;
   int len = strlen (base_file_name);
   const char *prefix = profile_data_prefix;
   /* + 1 for extra '/', in case prefix doesn't end with /.  */
@@ -1516,7 +1630,6 @@ get_da_file_name (const char *base_file_name)
   /* Name of da file.  */
   da_file_name = XNEWVEC (char, len + strlen (GCOV_DATA_SUFFIX)
 			  + prefix_len + 1);
-  da_base_file_name = XNEWVEC (char, len + 1);
 
   if (prefix)
     {
@@ -1528,7 +1641,7 @@ get_da_file_name (const char *base_file_name)
     da_file_name[0] = 0;
   strcat (da_file_name, base_file_name);
   strcat (da_file_name, GCOV_DATA_SUFFIX);
-  strcpy (da_base_file_name, base_file_name);
+  return da_file_name;
 }
 
 /* Rebuild counts_hash already built the primary module. This hashtable
@@ -1640,7 +1753,9 @@ coverage_init (const char *filename, const char* source_name)
   int src_name_prefix_len = 0;
   int len = strlen (filename);
 
-  get_da_file_name (filename);
+  da_file_name = get_da_file_name (filename);
+  da_base_file_name = XNEWVEC (char, strlen (filename) + 1);
+  strcpy (da_base_file_name, filename);
 
   /* Name of bbg file.  */
   bbg_file_name = XNEWVEC (char, len + strlen (GCOV_NOTE_SUFFIX) + 1);
@@ -1670,17 +1785,11 @@ coverage_init (const char *filename, const char* source_name)
   if (flag_profile_use && L_IPO_COMP_MODE)
     {
       unsigned i;
-      char *da_file_name_p = da_file_name;
-      char *da_base_file_name_p = da_base_file_name;
       gcc_assert (flag_dyn_ipa);
       rebuild_counts_hash ();
       for (i = 1; i < num_in_fnames; i++)
-        {
-          get_da_file_name (module_infos[i]->da_filename);
-          read_counts_file (da_file_name, module_infos[i]->ident);
-        }
-      da_file_name = da_file_name_p;
-      da_base_file_name = da_base_file_name_p;
+	read_counts_file (get_da_file_name (module_infos[i]->da_filename),
+			  module_infos[i]->ident);
     }
 }
 
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 77568998a44..84018510b46 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -253,7 +253,7 @@ Objective-C and Objective-C++ Dialects}.
 -Wparentheses  -Wpedantic-ms-format -Wno-pedantic-ms-format @gol
 -Wpointer-arith  -Wno-pointer-to-int-cast @gol
 -Wredundant-decls @gol
--Wreturn-type  -Wsequence-point  -Wshadow @gol
+-Wreturn-type  -Wripa-opt-mismatch  -Wsequence-point  -Wshadow @gol
 -Wsign-compare  -Wsign-conversion  -Wstack-protector @gol
 -Wstrict-aliasing -Wstrict-aliasing=n @gol
 -Wstrict-overflow -Wstrict-overflow=@var{n} @gol
@@ -333,7 +333,7 @@ Objective-C and Objective-C++ Dialects}.
 -fcheck-data-deps -fconserve-stack -fcprop-registers -fcrossjumping @gol
 -fcse-follow-jumps -fcse-skip-blocks -fcx-fortran-rules -fcx-limited-range @gol
 -fdata-sections -fdce -fdce @gol
--fdelayed-branch -fdelete-null-pointer-checks -fdse -fdse -fripa @gol
+-fdelayed-branch -fdelete-null-pointer-checks -fdse -fdse @gol
 -fearly-inlining -fexpensive-optimizations -ffast-math @gol
 -ffinite-math-only -ffloat-store -fexcess-precision=@var{style} @gol
 -fforward-propagate -ffunction-sections @gol
@@ -363,7 +363,7 @@ Objective-C and Objective-C++ Dialects}.
 -freciprocal-math -fregmove -frename-registers -freorder-blocks @gol
 -freorder-blocks-and-partition -freorder-functions @gol
 -frerun-cse-after-loop -freschedule-modulo-scheduled-loops @gol
--frounding-math -fsched2-use-superblocks @gol
+-fripa -fripa-disallow-opt-mismatch -frounding-math -fsched2-use-superblocks @gol
 -fsched2-use-traces -fsched-spec-load -fsched-spec-load-dangerous @gol
 -fsched-stalled-insns-dep[=@var{n}] -fsched-stalled-insns[=@var{n}] @gol
 -fsched-group-heuristic -fsched-critical-path-heuristic @gol
@@ -2803,6 +2803,7 @@ Options} and @ref{Objective-C and Objective-C++ Dialect Options}.
 -Wpointer-sign  @gol
 -Wreorder   @gol
 -Wreturn-type  @gol
+-Wripa-opt-mismatch @gol
 -Wsequence-point  @gol
 -Wsign-compare @r{(only in C++)}  @gol
 -Wstrict-aliasing  @gol
@@ -3207,6 +3208,16 @@ exceptions are @samp{main} and functions defined in system headers.
 
 This warning is enabled by @option{-Wall}.
 
+@item -Wripa-opt-mismatch
+@opindex Wripa-opt-mismatch
+@opindex Wno-ripa-opt-mismatch
+When doing an FDO build with @option{-fprofile-use} and @option{-fripa},
+warn if importing an axuiliary module that was built with a different
+GCC command line during the profile-generate phase than the primary
+module.
+
+This warning is enabled by @option{-Wall}.
+
 @item -Wswitch
 @opindex Wswitch
 @opindex Wno-switch
@@ -7103,6 +7114,13 @@ During the @option{-fprofile-generate} phase, this flag turns on some additional
 instrumentation code that enables dynamic call-graph analysis.
 During the @option{-fprofile-use} phase, this flag enables cross-module
 optimizations such as inlining.
+
+@item -fripa-disallow-opt-mismatch
+@opindex fripa-disallow-opt-mismatch
+Don't import an auxiliary module, if the GCC command line options used for this
+auxiliary module during the profile-generate stage were different from those used
+for the primary module. Note that any mismatches in warning-related options are
+ignored for this comparison.
 @end table
 
 The following options control compiler behavior regarding floating
diff --git a/gcc/dyn-ipa.c b/gcc/dyn-ipa.c
index 99b7fd25adb..9353535f780 100644
--- a/gcc/dyn-ipa.c
+++ b/gcc/dyn-ipa.c
@@ -1011,7 +1011,7 @@ gcov_write_module_info (const struct gcov_info *mod_info,
   len += 2; /* each name string is led by a length.  */
 
   num_strings = module_info->num_quote_paths + module_info->num_bracket_paths +
-    module_info->num_cpp_defines;
+    module_info->num_cpp_defines + module_info->num_cl_args;
   for (i = 0; i < num_strings; i++)
     {
       gcov_unsigned_t string_len
@@ -1021,7 +1021,7 @@ gcov_write_module_info (const struct gcov_info *mod_info,
       len += 1; /* Each string is lead by a length.  */
     }
 
-  len += 7; /* 7 more fields */
+  len += 8; /* 8 more fields */
 
   gcov_write_tag_length (GCOV_TAG_MODULE_INFO, len);
   gcov_write_unsigned (module_info->ident);
@@ -1031,6 +1031,7 @@ gcov_write_module_info (const struct gcov_info *mod_info,
   gcov_write_unsigned (module_info->num_quote_paths);
   gcov_write_unsigned (module_info->num_bracket_paths);
   gcov_write_unsigned (module_info->num_cpp_defines);
+  gcov_write_unsigned (module_info->num_cl_args);
 
   /* Now write the filenames */
   aligned_fname = (gcov_unsigned_t *) alloca ((filename_len + src_filename_len + 2) *
diff --git a/gcc/gcov-io.c b/gcc/gcov-io.c
index 1e351f1cb3b..833f7ae1215 100644
--- a/gcc/gcov-io.c
+++ b/gcc/gcov-io.c
@@ -511,7 +511,8 @@ gcov_read_module_info (struct gcov_module_info *mod_info,
   mod_info->num_quote_paths = gcov_read_unsigned ();
   mod_info->num_bracket_paths = gcov_read_unsigned ();
   mod_info->num_cpp_defines = gcov_read_unsigned ();
-  len -= 7;
+  mod_info->num_cl_args = gcov_read_unsigned ();
+  len -= 8;
 
   filename_len = gcov_read_unsigned ();
   mod_info->da_filename = (char *) xmalloc (filename_len *
@@ -528,7 +529,7 @@ gcov_read_module_info (struct gcov_module_info *mod_info,
   len -= (src_filename_len + 1);
 
   num_strings = mod_info->num_quote_paths + mod_info->num_bracket_paths +
-    mod_info->num_cpp_defines;
+    mod_info->num_cpp_defines + mod_info->num_cl_args;
   for (j = 0; j < num_strings; j++)
    {
      gcov_unsigned_t string_len = gcov_read_unsigned ();
diff --git a/gcc/gcov-io.h b/gcc/gcov-io.h
index e88db363069..4fccc63e0a3 100644
--- a/gcc/gcov-io.h
+++ b/gcc/gcov-io.h
@@ -470,6 +470,7 @@ struct gcov_module_info
   gcov_unsigned_t num_quote_paths;
   gcov_unsigned_t num_bracket_paths;
   gcov_unsigned_t num_cpp_defines;
+  gcov_unsigned_t num_cl_args;
   char *string_array[1];
 };
 
diff --git a/gcc/opts.c b/gcc/opts.c
index cb43729edac..cc0bff14ac9 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -731,6 +731,37 @@ flag_instrument_functions_exclude_p (tree fndecl)
   return false;
 }
 
+/* GCC command-line options saved to the LIPO profile data file.
+   See detailed comment in opts.h.  */
+const char **lipo_cl_args;
+unsigned num_lipo_cl_args;
+
+/* Inspect the given GCC command-line arguments, which are part of one GCC
+   switch, and decide whether or not to store these to the LIPO profile data
+   file.  */
+static void
+lipo_save_cl_args (unsigned int argc, const char **argv)
+{
+  unsigned int i;
+  const char *opt = argv[0];
+  /* Store the following command-line flags to the lipo profile data file:
+     (1) -f... (except -frandom-seed...)
+     (2) -m...
+     (3) -W...
+     (4) -O...
+     (5) --param...
+  */
+  if (opt[0] == '-'
+      && (opt[1] == 'f' || opt[1] == 'm' || opt[1] == 'W' || opt[1] == 'O'
+	  || (strstr (opt, "--param") == opt))
+      && !strstr(opt, "-frandom-seed"))
+    {
+      num_lipo_cl_args += argc;
+      lipo_cl_args = XRESIZEVEC (const char *, lipo_cl_args, num_lipo_cl_args);
+      for (i = 0; i < argc; i++)
+	lipo_cl_args[num_lipo_cl_args - argc + i] = argv[i];
+    }
+}
 
 /* Decode and handle the vector of command line options.  LANG_MASK
    contains has a single bit set representing the current
@@ -766,6 +797,8 @@ handle_options (unsigned int argc, const char **argv, unsigned int lang_mask)
 
       n = handle_option (argv + i, lang_mask);
 
+      lipo_save_cl_args (n, argv + i);
+
       if (!n)
 	{
 	  n = 1;
diff --git a/gcc/opts.h b/gcc/opts.h
index 7a13fb705cf..590f6c14a71 100644
--- a/gcc/opts.h
+++ b/gcc/opts.h
@@ -98,6 +98,15 @@ extern const char **in_fnames;
 
 extern unsigned num_in_fnames;
 
+/* GCC command-line arguments used during profile-gen, that are saved to the
+   profile data file. During profile-use, these can be compared to make sure
+   only those auxiliary modules are actually imported that use a compatible
+   set of GCC flags as the primary module.  */
+extern const char **lipo_cl_args;
+
+/* The size of the above mentioned mentioned array.  */
+extern unsigned num_lipo_cl_args;
+
 size_t find_opt (const char *input, int lang_mask);
 extern void prune_options (int *argcp, char ***argvp);
 extern void decode_options (unsigned int argc, const char **argv);