@SGaist
And function update_vars() is:
151 static void
152 internal_function
153 update_vars (void)
154 {
155 __daylight = tz_rules[0].offset != tz_rules[1].offset;
156 __timezone = -tz_rules[0].offset;
157 __tzname[0] = (char *) tz_rules[0].name;
158 __tzname[1] = (char *) tz_rules[1].name;
159
160 /* Keep __tzname_cur_max up to date. */
161 size_t len0 = strlen (__tzname[0]);
162 size_t len1 = strlen (__tzname[1]);
163 if (len0 > __tzname_cur_max)
164 __tzname_cur_max = len0;
165 if (len1 > __tzname_cur_max)
166 __tzname_cur_max = len1;
167 }