2017-10-11  Nathan Sidwell  <nathan@acm.org>

	gcc/
	* incpath.h (enum incpath_e): Name enum, prefix values.
	(add_path, add_cpp_dir_path, get_added_cpp_dirs): Use incpath_e type.
	* incpath.c (heads, tails): Use INC_MAX.
	(add_env_var_paths, add_standard_paths): Use incpath_e type.
	(merge_include_chains, split_quote_chain,
	register_include_chains): Update incpath_e names.
	(add_cpp_dir_path, add_path, get_added_cpp_dirs): Use incpath_e type.
	* config/darwin-c.c (add_system_framework_path): Update incpath_e
	names.
	(add_framework_path, darwin_register_objc_includes ): Likewise.
	* config/vms/vms-c.c (vms_c_register_includes): Likewise.

	c-family/
	* c-opts.c (add_prefixed_path): Change chain to incpath_e type.
	(c_common_handle_option): Update incpath_e names.

	fortran/
	* cpp.c (gfc_cpp_add_include_path): Update incpath_e names.
	(gfc_cpp_add_include_path_after): Likewise.

Index: incpath.h
===================================================================
--- incpath.h	(revision 253649)
+++ incpath.h	(working copy)
@@ -18,13 +18,22 @@
 #ifndef GCC_INCPATH_H
 #define GCC_INCPATH_H
 
+/* Various fragments of include path.  */
+enum incpath_kind {
+  INC_QUOTE = 0, /* include "foo" */
+  INC_BRACKET,   /* include <foo> */
+  INC_SYSTEM,    /* sysinclude */
+  INC_AFTER,	/* post-sysinclude.  */
+  INC_MAX
+};
+
 extern void split_quote_chain (void);
-extern void add_path (char *, int, int, bool);
+extern void add_path (char *, incpath_kind, int, bool);
 extern void register_include_chains (cpp_reader *, const char *,
 				     const char *, const char *,
 				     int, int, int);
-extern void add_cpp_dir_path (struct cpp_dir *, int);
-extern struct cpp_dir *get_added_cpp_dirs (int);
+extern void add_cpp_dir_path (struct cpp_dir *, incpath_kind);
+extern struct cpp_dir *get_added_cpp_dirs (incpath_kind);
 
 struct target_c_incpath_s {
   /* Do extra includes processing.  STDINC is false iff -nostdinc was given.  */
@@ -34,6 +43,4 @@ struct target_c_incpath_s {
 
 extern struct target_c_incpath_s target_c_incpath;
 
-enum { QUOTE = 0, BRACKET, SYSTEM, AFTER };
-
 #endif /* GCC_INCPATH_H */
Index: c-family/c-opts.c
===================================================================
--- c-family/c-opts.c	(revision 253649)
+++ c-family/c-opts.c	(working copy)
@@ -118,7 +118,7 @@ static void set_std_c11 (int);
 static void check_deps_environment_vars (void);
 static void handle_deferred_opts (void);
 static void sanitize_cpp_opts (void);
-static void add_prefixed_path (const char *, size_t);
+static void add_prefixed_path (const char *, incpath_kind);
 static void push_command_line_include (void);
 static void cb_file_change (cpp_reader *, const line_map_ordinary *);
 static void cb_dir_change (cpp_reader *, const char *);
@@ -316,7 +316,7 @@ c_common_handle_option (size_t scode, co
 
     case OPT_I:
       if (strcmp (arg, "-"))
-	add_path (xstrdup (arg), BRACKET, 0, true);
+	add_path (xstrdup (arg), INC_BRACKET, 0, true);
       else
 	{
 	  if (quote_chain_split)
@@ -550,7 +550,7 @@ c_common_handle_option (size_t scode, co
       break;
 
     case OPT_idirafter:
-      add_path (xstrdup (arg), AFTER, 0, true);
+      add_path (xstrdup (arg), INC_AFTER, 0, true);
       break;
 
     case OPT_imacros:
@@ -567,7 +567,7 @@ c_common_handle_option (size_t scode, co
       break;
 
     case OPT_iquote:
-      add_path (xstrdup (arg), QUOTE, 0, true);
+      add_path (xstrdup (arg), INC_QUOTE, 0, true);
       break;
 
     case OPT_isysroot:
@@ -575,15 +575,15 @@ c_common_handle_option (size_t scode, co
       break;
 
     case OPT_isystem:
-      add_path (xstrdup (arg), SYSTEM, 0, true);
+      add_path (xstrdup (arg), INC_SYSTEM, 0, true);
       break;
 
     case OPT_iwithprefix:
-      add_prefixed_path (arg, SYSTEM);
+      add_prefixed_path (arg, INC_SYSTEM);
       break;
 
     case OPT_iwithprefixbefore:
-      add_prefixed_path (arg, BRACKET);
+      add_prefixed_path (arg, INC_BRACKET);
       break;
 
     case OPT_lang_asm:
@@ -1326,7 +1326,7 @@ sanitize_cpp_opts (void)
 
 /* Add include path with a prefix at the front of its name.  */
 static void
-add_prefixed_path (const char *suffix, size_t chain)
+add_prefixed_path (const char *suffix, incpath_kind chain)
 {
   char *path;
   const char *prefix;
Index: config/darwin-c.c
===================================================================
--- config/darwin-c.c	(revision 253649)
+++ config/darwin-c.c	(working copy)
@@ -433,7 +433,7 @@ add_system_framework_path (char *path)
   p->construct = framework_construct_pathname;
   using_frameworks = 1;
 
-  add_cpp_dir_path (p, SYSTEM);
+  add_cpp_dir_path (p, INC_SYSTEM);
 }
 
 /* Add PATH to the bracket includes. PATH must be malloc-ed and
@@ -451,7 +451,7 @@ add_framework_path (char *path)
   p->construct = framework_construct_pathname;
   using_frameworks = 1;
 
-  add_cpp_dir_path (p, BRACKET);
+  add_cpp_dir_path (p, INC_BRACKET);
 }
 
 static const char *framework_defaults [] =
@@ -488,7 +488,7 @@ darwin_register_objc_includes (const cha
 	{
 	  str = concat (iprefix, fname + len, NULL);
           /* FIXME: wrap the headers for C++awareness.  */
-	  add_path (str, SYSTEM, /*c++aware=*/false, false);
+	  add_path (str, INC_SYSTEM, /*c++aware=*/false, false);
 	}
 
       /* Should this directory start with the sysroot?  */
@@ -497,7 +497,7 @@ darwin_register_objc_includes (const cha
       else
 	str = update_path (fname, "");
 
-      add_path (str, SYSTEM, /*c++aware=*/false, false);
+      add_path (str, INC_SYSTEM, /*c++aware=*/false, false);
     }
 }
 
Index: config/vms/vms-c.c
===================================================================
--- config/vms/vms-c.c	(revision 253649)
+++ config/vms/vms-c.c	(working copy)
@@ -418,7 +418,7 @@ vms_c_register_includes (const char *sys
   if (!stdinc)
     return;
 
-  for (dir = get_added_cpp_dirs (SYSTEM); dir != NULL; dir = dir->next)
+  for (dir = get_added_cpp_dirs (INC_SYSTEM); dir != NULL; dir = dir->next)
     {
       const char * const *lib;
       for (lib = vms_std_modules; *lib != NULL; lib++)
@@ -441,7 +441,7 @@ vms_c_register_includes (const char *sys
               p->sysp = 1;
               p->construct = vms_construct_include_filename;
               p->user_supplied_p = 0;
-              add_cpp_dir_path (p, SYSTEM);
+              add_cpp_dir_path (p, INC_SYSTEM);
             }
           else
             free (path);
Index: fortran/cpp.c
===================================================================
--- fortran/cpp.c	(revision 253649)
+++ fortran/cpp.c	(working copy)
@@ -683,14 +683,14 @@ gfc_cpp_add_include_path (char *path, bo
      include path. Fortran does not define any system include paths.  */
   int cxx_aware = 0;
 
-  add_path (path, BRACKET, cxx_aware, user_supplied);
+  add_path (path, INC_BRACKET, cxx_aware, user_supplied);
 }
 
 void
 gfc_cpp_add_include_path_after (char *path, bool user_supplied)
 {
   int cxx_aware = 0;
-  add_path (path, AFTER, cxx_aware, user_supplied);
+  add_path (path, INC_AFTER, cxx_aware, user_supplied);
 }
 
 void
Index: incpath.c
===================================================================
--- incpath.c	(revision 253649)
+++ incpath.c	(working copy)
@@ -46,7 +46,7 @@
 
 static const char dir_separator_str[] = { DIR_SEPARATOR, 0 };
 
-static void add_env_var_paths (const char *, int);
+static void add_env_var_paths (const char *, incpath_kind);
 static void add_standard_paths (const char *, const char *, const char *, int);
 static void free_path (struct cpp_dir *, int);
 static void merge_include_chains (const char *, cpp_reader *, int);
@@ -56,8 +56,9 @@ static struct cpp_dir *remove_duplicates
 					   struct cpp_dir *, int);
 
 /* Include chains heads and tails.  */
-static struct cpp_dir *heads[4];
-static struct cpp_dir *tails[4];
+static struct cpp_dir *heads[INC_MAX];
+static struct cpp_dir *tails[INC_MAX];
+
 static bool quote_ignores_source_dir;
 enum { REASON_QUIET = 0, REASON_NOENT, REASON_DUP, REASON_DUP_SYS };
 
@@ -92,7 +93,7 @@ free_path (struct cpp_dir *path, int rea
 /* Read ENV_VAR for a PATH_SEPARATOR-separated list of file names; and
    append all the names to the search path CHAIN.  */
 static void
-add_env_var_paths (const char *env_var, int chain)
+add_env_var_paths (const char *env_var, incpath_kind chain)
 {
   char *p, *q, *path;
 
@@ -116,7 +117,7 @@ add_env_var_paths (const char *env_var,
 	  path[q - p] = '\0';
 	}
 
-      add_path (path, chain, chain == SYSTEM, false);
+      add_path (path, chain, chain == INC_SYSTEM, false);
     }
 }
 
@@ -159,7 +160,7 @@ add_standard_paths (const char *sysroot,
 		      str = reconcat (str, str, dir_separator_str,
 				      imultiarch, NULL);
 		    }
-		  add_path (str, SYSTEM, p->cxx_aware, false);
+		  add_path (str, INC_SYSTEM, p->cxx_aware, false);
 		}
 	    }
 	}
@@ -225,7 +226,7 @@ add_standard_paths (const char *sysroot,
 	      str = reconcat (str, str, dir_separator_str, imultiarch, NULL);
 	    }
 
-	  add_path (str, SYSTEM, p->cxx_aware, false);
+	  add_path (str, INC_SYSTEM, p->cxx_aware, false);
 	}
     }
 }
@@ -349,29 +350,32 @@ merge_include_chains (const char *sysroo
   /* Add the sysroot to user-supplied paths starting with "=".  */
   if (sysroot)
     {
-      add_sysroot_to_chain (sysroot, QUOTE);
-      add_sysroot_to_chain (sysroot, BRACKET);
-      add_sysroot_to_chain (sysroot, SYSTEM);
-      add_sysroot_to_chain (sysroot, AFTER);
+      add_sysroot_to_chain (sysroot, INC_QUOTE);
+      add_sysroot_to_chain (sysroot, INC_BRACKET);
+      add_sysroot_to_chain (sysroot, INC_SYSTEM);
+      add_sysroot_to_chain (sysroot, INC_AFTER);
     }
 
   /* Join the SYSTEM and AFTER chains.  Remove duplicates in the
      resulting SYSTEM chain.  */
-  if (heads[SYSTEM])
-    tails[SYSTEM]->next = heads[AFTER];
+  if (heads[INC_SYSTEM])
+    tails[INC_SYSTEM]->next = heads[INC_AFTER];
   else
-    heads[SYSTEM] = heads[AFTER];
-  heads[SYSTEM] = remove_duplicates (pfile, heads[SYSTEM], 0, 0, verbose);
+    heads[INC_SYSTEM] = heads[INC_AFTER];
+  heads[INC_SYSTEM]
+    = remove_duplicates (pfile, heads[INC_SYSTEM], 0, 0, verbose);
 
   /* Remove duplicates from BRACKET that are in itself or SYSTEM, and
      join it to SYSTEM.  */
-  heads[BRACKET] = remove_duplicates (pfile, heads[BRACKET], heads[SYSTEM],
-				      heads[SYSTEM], verbose);
+  heads[INC_BRACKET]
+    = remove_duplicates (pfile, heads[INC_BRACKET], heads[INC_SYSTEM],
+			 heads[INC_SYSTEM], verbose);
 
   /* Remove duplicates from QUOTE that are in itself or SYSTEM, and
      join it to BRACKET.  */
-  heads[QUOTE] = remove_duplicates (pfile, heads[QUOTE], heads[SYSTEM],
-				    heads[BRACKET], verbose);
+  heads[INC_QUOTE]
+    = remove_duplicates (pfile, heads[INC_QUOTE], heads[INC_SYSTEM],
+			 heads[INC_BRACKET], verbose);
 
   /* If verbose, print the list of dirs to search.  */
   if (verbose)
@@ -379,9 +383,9 @@ merge_include_chains (const char *sysroo
       struct cpp_dir *p;
 
       fprintf (stderr, _("#include \"...\" search starts here:\n"));
-      for (p = heads[QUOTE];; p = p->next)
+      for (p = heads[INC_QUOTE];; p = p->next)
 	{
-	  if (p == heads[BRACKET])
+	  if (p == heads[INC_BRACKET])
 	    fprintf (stderr, _("#include <...> search starts here:\n"));
 	  if (!p)
 	    break;
@@ -398,14 +402,14 @@ merge_include_chains (const char *sysroo
 void
 split_quote_chain (void)
 {
-  if (heads[QUOTE])
-    free_path (heads[QUOTE], REASON_QUIET);
-  if (tails[QUOTE])
-    free_path (tails[QUOTE], REASON_QUIET);
-  heads[QUOTE] = heads[BRACKET];
-  tails[QUOTE] = tails[BRACKET];
-  heads[BRACKET] = NULL;
-  tails[BRACKET] = NULL;
+  if (heads[INC_QUOTE])
+    free_path (heads[INC_QUOTE], REASON_QUIET);
+  if (tails[INC_QUOTE])
+    free_path (tails[INC_QUOTE], REASON_QUIET);
+  heads[INC_QUOTE] = heads[INC_BRACKET];
+  tails[INC_QUOTE] = tails[INC_BRACKET];
+  heads[INC_BRACKET] = NULL;
+  tails[INC_BRACKET] = NULL;
   /* This is NOT redundant.  */
   quote_ignores_source_dir = true;
 }
@@ -413,7 +417,7 @@ split_quote_chain (void)
 /* Add P to the chain specified by CHAIN.  */
 
 void
-add_cpp_dir_path (cpp_dir *p, int chain)
+add_cpp_dir_path (cpp_dir *p, incpath_kind chain)
 {
   if (tails[chain])
     tails[chain]->next = p;
@@ -425,7 +429,7 @@ add_cpp_dir_path (cpp_dir *p, int chain)
 /* Add PATH to the include chain CHAIN. PATH must be malloc-ed and
    NUL-terminated.  */
 void
-add_path (char *path, int chain, int cxx_aware, bool user_supplied_p)
+add_path (char *path, incpath_kind chain, int cxx_aware, bool user_supplied_p)
 {
   cpp_dir *p;
 
@@ -450,7 +454,7 @@ add_path (char *path, int chain, int cxx
 #ifndef INO_T_EQ
   p->canonical_name = lrealpath (path);
 #endif
-  if (chain == SYSTEM || chain == AFTER)
+  if (chain == INC_SYSTEM || chain == INC_AFTER)
     p->sysp = 1 + !cxx_aware;
   else
     p->sysp = 0;
@@ -480,8 +484,8 @@ register_include_chains (cpp_reader *pfi
 
   /* CPATH and language-dependent environment variables may add to the
      include chain.  */
-  add_env_var_paths ("CPATH", BRACKET);
-  add_env_var_paths (lang_env_vars[idx], SYSTEM);
+  add_env_var_paths ("CPATH", INC_BRACKET);
+  add_env_var_paths (lang_env_vars[idx], INC_SYSTEM);
 
   target_c_incpath.extra_pre_includes (sysroot, iprefix, stdinc);
 
@@ -493,14 +497,14 @@ register_include_chains (cpp_reader *pfi
 
   merge_include_chains (sysroot, pfile, verbose);
 
-  cpp_set_include_chains (pfile, heads[QUOTE], heads[BRACKET],
+  cpp_set_include_chains (pfile, heads[INC_QUOTE], heads[INC_BRACKET],
 			  quote_ignores_source_dir);
 }
 
 /* Return the current chain of cpp dirs.  */
 
 struct cpp_dir *
-get_added_cpp_dirs (int chain)
+get_added_cpp_dirs (incpath_kind chain)
 {
   return heads[chain];
 }
