reserved_word: just use gperf 3.1 declaration

The reason why this was commented out was because of gperf 3.0 vs 3.1
differences (see [Feature #13883]).  Five years passed, I am pretty
confident that we can drop support of old versions here.

Ditto for uniname2ctype_p(), onig_jis_property(), and zonetab().

defs/keywords

@@ -2,7 +2,7 @@
 struct kwtable {short name, id[2], state;};
 const struct kwtable *rb_reserved_word(const char *, unsigned int);
 #ifndef RIPPER
-static const struct kwtable *reserved_word(/*!ANSI{*/const char *, unsigned int/*}!ANSI*/);
+static const struct kwtable *reserved_word(register const char *str, register size_t len);
 #define rb_reserved_word(str, len) reserved_word(str, len)
 %}
 

defs/lex.c.src

@@ -2,7 +2,7 @@
 struct kwtable {short name, id[2], state;};
 const struct kwtable *rb_reserved_word(const char *, unsigned int);
 #ifndef RIPPER
-static const struct kwtable *reserved_word(/*!ANSI{*/const char *, unsigned int/*}!ANSI*/);
+static const struct kwtable *reserved_word(register const char *str, register size_t len);
 #define rb_reserved_word(str, len) reserved_word(str, len)
 %}
 

enc/jis/props.h.blt

@@ -69,7 +69,7 @@ struct enc_property {
     unsigned char ctype;
 };
 
-static const struct enc_property *onig_jis_property(/*const char *str, unsigned int len*/);
+static const struct enc_property *onig_jis_property(register const char *str, register size_t len);
 #line 43 "enc/jis/props.kwd"
 struct enc_property;
 
@@ -82,7 +82,7 @@ struct enc_property;
 
 #ifndef GPERF_DOWNCASE
 #define GPERF_DOWNCASE 1
-static unsigned char gperf_downcase[256] =
+static const unsigned char gperf_downcase[256] =
   {
       0,   1,   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,  12,  13,  14,
      15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,

enc/jis/props.kwd

@@ -37,7 +37,7 @@ struct enc_property {
     unsigned char ctype;
 };
 
-static const struct enc_property *onig_jis_property(/*!ANSI{*/const char *str, unsigned int len/*}!ANSI*/);
+static const struct enc_property *onig_jis_property(register const char *str, register size_t len);
 %}
 
 struct enc_property;

enc/jis/props.src

@@ -37,7 +37,7 @@ struct enc_property {
     unsigned char ctype;
 };
 
-static const struct enc_property *onig_jis_property(/*!ANSI{*/const char *str, unsigned int len/*}!ANSI*/);
+static const struct enc_property *onig_jis_property(register const char *str, register size_t len);
 %}
 
 struct enc_property;

enc/unicode/14.0.0/name2ctype.h

@@ -40642,11 +40642,7 @@ struct uniname2ctype_struct {
 };
 #define uniname2ctype_offset(str) offsetof(struct uniname2ctype_pool_t, uniname2ctype_pool_##str)
 
-static const struct uniname2ctype_struct *uniname2ctype_p(
-#if !(1+0) /* if ANSI, old style not to conflict with generated prototype */
-    const char *, unsigned int
-#endif
-);
+static const struct uniname2ctype_struct *uniname2ctype_p(register const char *str, register size_t len);
 
 #ifndef USE_UNICODE_PROPERTIES
 #define TOTAL_KEYWORDS 15

ext/date/zonetab.h

@@ -36,7 +36,7 @@ struct zone {
     int name;
     int offset;
 };
-static const struct zone *zonetab();
+static const struct zone *zonetab(register const char *str, register size_t len);
 #line 9 "zonetab.list"
 struct zone;
 

ext/date/zonetab.list

@@ -3,7 +3,7 @@ struct zone {
     int name;
     int offset;
 };
-static const struct zone *zonetab();
+static const struct zone *zonetab(register const char *str, register size_t len);
 %}
 
 struct zone;

lex.c.blt

@@ -34,7 +34,7 @@
 struct kwtable {short name, id[2], state;};
 const struct kwtable *rb_reserved_word(const char *, unsigned int);
 #ifndef RIPPER
-static const struct kwtable *reserved_word(/*const char *, unsigned int*/);
+static const struct kwtable *reserved_word(register const char *str, register size_t len);
 #define rb_reserved_word(str, len) reserved_word(str, len)
 #line 9 "defs/keywords"
 struct kwtable;

tool/enc-unicode.rb

@@ -465,11 +465,7 @@ struct uniname2ctype_struct {
 };
 #define uniname2ctype_offset(str) offsetof(struct uniname2ctype_pool_t, uniname2ctype_pool_##str)
 
-static const struct uniname2ctype_struct *uniname2ctype_p(
-#if !(/*ANSI*/+0) /* if ANSI, old style not to conflict with generated prototype */
-    const char *, unsigned int
-#endif
-);
+static const struct uniname2ctype_struct *uniname2ctype_p(register const char *str, register size_t len);
 %}
 struct uniname2ctype_struct;
 %%