ext/date: constify

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55318 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/date/date_core.c

@@ -6602,7 +6602,7 @@ tmx_m_zone(union DateData *x)
     return RSTRING_PTR(m_zone(x));
 }
 
-static struct tmx_funcs tmx_funcs = {
+static const struct tmx_funcs tmx_funcs = {
     (VALUE (*)(void *))m_real_year,
     (int (*)(void *))m_yday,
     (int (*)(void *))m_mon,

ext/date/date_parse.c

@@ -44,12 +44,12 @@
 #define cstr2num(s) rb_cstr_to_inum(s, 10, 0)
 #define str2num(s) rb_str_to_inum(s, 10, 0)
 
-static const char *abbr_days[] = {
+static const char abbr_days[][4] = {
     "sun", "mon", "tue", "wed",
     "thu", "fri", "sat"
 };
 
-static const char *abbr_months[] = {
+static const char abbr_months[][4] = {
     "jan", "feb", "mar", "apr", "may", "jun",
     "jul", "aug", "sep", "oct", "nov", "dec"
 };
@@ -342,7 +342,7 @@ struct zone {
     int offset;
 };
 
-static struct zone zones_source[] = {
+static const struct zone zones_source[] = {
     {"ut",   0*3600}, {"gmt",  0*3600}, {"est", -5*3600}, {"edt", -4*3600},
     {"cst", -6*3600}, {"cdt", -5*3600}, {"mst", -7*3600}, {"mdt", -6*3600},
     {"pst", -8*3600}, {"pdt", -7*3600},

ext/date/date_tmx.h

@@ -23,7 +23,7 @@ struct tmx_funcs {
 };
 struct tmx {
     void *dat;
-    struct tmx_funcs *funcs;
+    const struct tmx_funcs *funcs;
 };
 
 #define tmx_attr(x) (tmx->funcs->x)(tmx->dat)