* TODO: Remove dead items.

[bison.git] / data / c.m4

diff --git a/data/c.m4 b/data/c.m4
index d84651079a680f86c63a9906cf60336c762b9867..f9066764cf53523684989805cebbf3d1b599a4e0 100644 (file)
--- a/data/c.m4
+++ b/data/c.m4
@@ -1,7 +1,7 @@
 m4_divert(-1)                                               -*- Autoconf -*-
 
 # C M4 Macros for Bison.
-# Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
+# Copyright (C) 2002, 2004, 2005, 2006 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -95,6 +95,7 @@ m4_define_default([b4_parse_param])
 m4_define([b4_parse_param],
 b4_parse_param))
 
+
 # b4_parse_param_for(DECL, FORMAL, BODY)
 # ---------------------------------------
 # Iterate over the user parameters, binding the declaration to DECL,
@@ -141,7 +142,7 @@ m4_define([b4_int_type],
 
        m4_eval([0 <= $1]),                [1], [unsigned int],
 
-                                              [int])])
+                                              [int])])
 
 
 # b4_int_type_for(NAME)
@@ -227,7 +228,7 @@ m4_define([b4_token_enums],
    enum yytokentype {
 m4_map_sep([     b4_token_enum], [,
 ],
-           [$@])
+          [$@])
    };
 #endif
 ])])
@@ -247,11 +248,25 @@ m4_define([b4_token_enums_defines],
 ## --------------------------------------------- ##
 
 
+# b4_modern_c
+# -----------
+# A predicate useful in #if to determine whether C is ancient or modern.
+#
+# If __STDC__ is defined, the compiler is modern.  IBM xlc 7.0 when run
+# as 'cc' doesn't define __STDC__ (or __STDC_VERSION__) for pedantic
+# reasons, but it defines __C99__FUNC__ so check that as well.
+# Microsoft C normally doesn't define these macros, but it defines _MSC_VER.
+# Consider a C++ compiler to be modern if it defines __cplusplus.
+#
+m4_define([b4_c_modern],
+  [[(defined __STDC__ || defined __C99__FUNC__ \
+     || defined __cplusplus || defined _MSC_VER)]])
+
 # b4_c_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
 # ----------------------------------------------------------
 # Declare the function NAME.
 m4_define([b4_c_function_def],
-[#if defined (__STDC__) || defined (__C99__FUNC__) || defined (__cplusplus)
+[#if b4_c_modern
 b4_c_ansi_function_def($@)
 #else
 $2
@@ -275,9 +290,9 @@ $1 (b4_c_ansi_formals(m4_shiftn(2, $@)))[]dnl
 # Output the arguments ANSI-C definition.
 m4_define([b4_c_ansi_formals],
 [m4_case([$@],
-         [],   [void],
-         [[]], [void],
-               [m4_map_sep([b4_c_ansi_formal], [, ], [$@])])])
+        [],   [void],
+        [[]], [void],
+              [m4_map_sep([b4_c_ansi_formal], [, ], [$@])])])
 
 m4_define([b4_c_ansi_formal],
 [$1])
@@ -298,9 +313,9 @@ m4_define([b4_c_knr_formal_name],
 # Output the K&R argument declarations.
 m4_define([b4_c_knr_formal_decls],
 [m4_map_sep([b4_c_knr_formal_decl],
-            [
+           [
 ],
-            [$@])])
+           [$@])])
 
 m4_define([b4_c_knr_formal_decl],
 [    $1;])
@@ -316,7 +331,7 @@ m4_define([b4_c_knr_formal_decl],
 # -----------------------------------------------------------
 # Declare the function NAME.
 m4_define([b4_c_function_decl],
-[#if defined (__STDC__) || defined (__cplusplus)
+[#if defined __STDC__ || defined __cplusplus
 b4_c_ansi_function_decl($@)
 #else
 $2 $1 ();
@@ -383,9 +398,9 @@ m4_define([b4_symbol_actions],
 m4_pushdef([b4_at_dollar], [(*yylocationp)])dnl
       case $4: /* $3 */
 b4_syncline([$2], [$1])
-        $5;
+       $5;
 b4_syncline([@oline@], [@ofile@])
-        break;
+       break;
 m4_popdef([b4_at_dollar])dnl
 m4_popdef([b4_dollar_dollar])dnl
 ])
@@ -423,7 +438,7 @@ b4_parse_param_use[]dnl
     {
 ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_destructors]))[
       default:
-        break;
+       break;
     }
 }]dnl
 ])
@@ -443,25 +458,28 @@ m4_define_default([b4_yy_symbol_print_generate],
 /*ARGSUSED*/
 ]$1([yy_symbol_value_print],
     [static void],
-               [[FILE *yyoutput],                       [yyoutput]],
-               [[int yytype],                           [yytype]],
-               [[const YYSTYPE * const yyvaluep],       [yyvaluep]][]dnl
+              [[FILE *yyoutput],                       [yyoutput]],
+              [[int yytype],                           [yytype]],
+              [[const YYSTYPE * const yyvaluep],       [yyvaluep]][]dnl
 b4_location_if([, [[const YYLTYPE * const yylocationp], [yylocationp]]])[]dnl
 m4_ifset([b4_parse_param], [, b4_parse_param]))[
 {
-  YYUSE (yyvaluep);
+  if (!yyvaluep)
+    return;
 ]b4_location_if([  YYUSE (yylocationp);
 ])dnl
 b4_parse_param_use[]dnl
 [# ifdef YYPRINT
   if (yytype < YYNTOKENS)
     YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
+# else
+  YYUSE (yyoutput);
 # endif
   switch (yytype)
     {
 ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 [      default:
-        break;
+       break;
     }
 }
 
@@ -472,9 +490,9 @@ b4_parse_param_use[]dnl
 
 ]$1([yy_symbol_print],
     [static void],
-               [[FILE *yyoutput],                       [yyoutput]],
-               [[int yytype],                           [yytype]],
-               [[const YYSTYPE * const yyvaluep],       [yyvaluep]][]dnl
+              [[FILE *yyoutput],                       [yyoutput]],
+              [[int yytype],                           [yytype]],
+              [[const YYSTYPE * const yyvaluep],       [yyvaluep]][]dnl
 b4_location_if([, [[const YYLTYPE * const yylocationp], [yylocationp]]])[]dnl
 m4_ifset([b4_parse_param], [, b4_parse_param]))[
 {