Move the integer-type selection into c.m4

That way, glr.c can use it too.
* data/skeletons/c.m4 (b4_int_type):
Do not special-case ‘char’; it’s not worth the trouble,
as clang complains about char subscripts.
(b4_c99_int_type, b4_c99_int_type_define): New macros,
taken from yacc.c.
* data/skeletons/glr.c: Use b4_int_type_define.
* data/skeletons/yacc.c (b4_int_type): Remove, since there’s
no longer any need to redefine it.
Use b4_c99_int_type_define rather than its body.

data/skeletons/c.m4

@@ -171,8 +171,7 @@ b4_parse_param_for([Decl], [Formal], [  YYUSE (Formal);
 # to MAX (included) in portable C code.  Assume MIN and MAX fall in
 # 'int' range.
 m4_define([b4_int_type],
-[m4_if(b4_ints_in($@,      [0],   [127]), [1], [char],
+[m4_if(b4_ints_in($@,   [-127],   [127]), [1], [signed char],
-       b4_ints_in($@,   [-127],   [127]), [1], [signed char],
        b4_ints_in($@,      [0],   [255]), [1], [unsigned char],
 
        b4_ints_in($@, [-32767], [32767]), [1], [short],
@@ -180,6 +179,80 @@ m4_define([b4_int_type],
 
                                                [int])])
 
+# b4_c99_int_type(MIN, MAX)
+# -------------------------
+# Like b4_int_type, but for C99.
+# b4_c99_int_type_define replaces b4_int_type with this.
+m4_define([b4_c99_int_type],
+[m4_if(b4_ints_in($@,   [-127],   [127]), [1], [yytype_int8],
+       b4_ints_in($@,      [0],   [255]), [1], [yytype_uint8],
+
+       b4_ints_in($@, [-32767], [32767]), [1], [yytype_int16],
+       b4_ints_in($@,      [0], [65535]), [1], [yytype_uint16],
+
+                                               [int])])
+
+# b4_c99_int_type_define
+# ----------------------
+# Define private types suitable for holding small integers in C99 or later.
+m4_define([b4_c99_int_type_define],
+[m4_copy_force([b4_c99_int_type], [b4_int_type])dnl
+[/* On compilers that do not define __PTRDIFF_MAX__ etc., make sure
+   <limits.h> and (if available) <stdint.h> are included
+   so that the code can choose integer types of a good width.  */
+
+#ifndef __PTRDIFF_MAX__
+# ifndef INT_MAX
+#  include <limits.h> /* INFRINGES ON USER NAME SPACE */
+# endif
+# ifndef PTRDIFF_MAX
+#  if defined __STDC_VERSION__ && 199901 <= __STDC_VERSION__
+#   include <stdint.h> /* INFRINGES ON USER NAME SPACE */
+#  endif
+# endif
+#endif
+
+/* Narrow types that promote to a signed type and that can represent a
+   signed or unsigned integer of at least N bits.  In tables they can
+   save space and decrease cache pressure.  Promoting to a signed type
+   helps avoid bugs in integer arithmetic.  */
+
+#if defined __UINT_LEAST8_MAX__ && __UINT_LEAST8_MAX__ <= __INT_MAX__
+typedef __UINT_LEAST8_TYPE__ yytype_uint8;
+#elif defined UINT_LEAST8_MAX && UINT_LEAST8_MAX <= INT_MAX
+typedef uint_least8_t yytype_uint8;
+#elif UCHAR_MAX <= INT_MAX
+typedef unsigned char yytype_uint8;
+#else
+typedef short yytype_uint8;
+#endif
+
+#if defined __INT_LEAST8_MAX__ && __INT_LEAST8_MAX__ <= __INT_MAX__
+typedef __INT_LEAST8_TYPE__ yytype_int8;
+#elif defined INT_LEAST8_MAX && INT_LEAST8_MAX <= INT_MAX
+typedef int_least8_t yytype_int8;
+#else
+typedef signed char yytype_int8;
+#endif
+
+#if defined __UINT_LEAST16_MAX__ && __UINT_LEAST16_MAX__ <= __INT_MAX__
+typedef __UINT_LEAST16_TYPE__ yytype_uint16;
+#elif defined UINT_LEAST16_MAX && UINT_LEAST16_MAX <= INT_MAX
+typedef uint_least16_t yytype_uint16;
+#elif USHRT_MAX <= INT_MAX
+typedef unsigned short yytype_uint16;
+#else
+typedef int yytype_uint16;
+#endif
+
+#if defined __INT_LEAST16_MAX__ && __INT_LEAST16_MAX__ <= __INT_MAX__
+typedef __INT_LEAST16_TYPE__ yytype_int16;
+#elif defined INT_LEAST16_MAX && INT_LEAST16_MAX <= INT_MAX
+typedef int_least16_t yytype_int16;
+#else
+typedef short yytype_int16;
+#endif]])
+
 
 # b4_int_type_for(NAME)
 # ---------------------

data/skeletons/glr.c

@@ -265,6 +265,8 @@ static YYLTYPE yyloc_default][]b4_yyloc_default;])[
 #include <stdlib.h>
 #include <string.h>
 
+]b4_c99_int_type_define[
+
 #ifndef YY_
 # if defined YYENABLE_NLS && YYENABLE_NLS
 #  if ENABLE_NLS

data/skeletons/yacc.c

@@ -106,25 +106,6 @@ m4_ifset([b4_parse_param], [b4_args(b4_parse_param), ])])
 
 
 
-## ------------ ##
-## Data Types.  ##
-## ------------ ##
-
-# b4_int_type(MIN, MAX)
-# ---------------------
-# Return a narrow int type able to handle numbers ranging from
-# MIN to MAX (included).  Overwrite the version from c.m4,
-# so that the code can use C99 types if available.
-m4_define([b4_int_type],
-[m4_if(b4_ints_in($@,   [-127],   [127]), [1], [yytype_int8],
-       b4_ints_in($@,      [0],   [255]), [1], [yytype_uint8],
-
-       b4_ints_in($@, [-32767], [32767]), [1], [yytype_int16],
-       b4_ints_in($@,      [0], [65535]), [1], [yytype_uint16],
-
-                                               [int])])
-
-
 ## ----------------- ##
 ## Semantic Values.  ##
 ## ----------------- ##
@@ -388,57 +369,7 @@ m4_if(b4_api_prefix, [yy], [],
 # undef short
 #endif
 
-/* On compilers that do not define __PTRDIFF_MAX__ etc., include
+]b4_c99_int_type_define[
-   <limits.h> and (if available) <stdint.h> so that the code can
-   choose integer types of a good width.  */
-
-#ifndef __PTRDIFF_MAX__
-# include <limits.h> /* INFRINGES ON USER NAME SPACE */
-# if defined __STDC_VERSION__ && 199901 <= __STDC_VERSION__
-#  include <stdint.h> /* INFRINGES ON USER NAME SPACE */
-# endif
-#endif
-
-/* Narrow types that promote to a signed type and that can represent a
-   signed or unsigned integer of at least N bits.  In tables they can
-   save space and decrease cache pressure.  Promoting to a signed type
-   helps avoid bugs in integer arithmetic.  */
-
-#if defined __UINT_LEAST8_MAX__ && __UINT_LEAST8_MAX__ <= __INT_MAX__
-typedef __UINT_LEAST8_TYPE__ yytype_uint8;
-#elif defined UINT_LEAST8_MAX && UINT_LEAST8_MAX <= INT_MAX
-typedef uint_least8_t yytype_uint8;
-#elif UCHAR_MAX <= INT_MAX
-typedef unsigned char yytype_uint8;
-#else
-typedef short yytype_uint8;
-#endif
-
-#if defined __INT_LEAST8_MAX__ && __INT_LEAST8_MAX__ <= __INT_MAX__
-typedef __INT_LEAST8_TYPE__ yytype_int8;
-#elif defined INT_LEAST8_MAX && INT_LEAST8_MAX <= INT_MAX
-typedef int_least8_t yytype_int8;
-#else
-typedef signed char yytype_int8;
-#endif
-
-#if defined __UINT_LEAST16_MAX__ && __UINT_LEAST16_MAX__ <= __INT_MAX__
-typedef __UINT_LEAST16_TYPE__ yytype_uint16;
-#elif defined UINT_LEAST16_MAX && UINT_LEAST16_MAX <= INT_MAX
-typedef uint_least16_t yytype_uint16;
-#elif USHRT_MAX <= INT_MAX
-typedef unsigned short yytype_uint16;
-#else
-typedef int yytype_uint16;
-#endif
-
-#if defined __INT_LEAST16_MAX__ && __INT_LEAST16_MAX__ <= __INT_MAX__
-typedef __INT_LEAST16_TYPE__ yytype_int16;
-#elif defined INT_LEAST16_MAX && INT_LEAST16_MAX <= INT_MAX
-typedef int_least16_t yytype_int16;
-#else
-typedef short yytype_int16;
-#endif
 
 #ifndef YYPTRDIFF_T
 # if defined __PTRDIFF_TYPE__ && defined __PTRDIFF_MAX__