+ ch = next_char (dm);
+
+ /* Handle extended Unicode characters. We encode them as __U{hex}_,
+ where {hex} omits leading 0's. For instance, '$' is encoded as
+ "__U24_". */
+ if (ch == '_'
+ && peek_char (dm) == '_'
+ && peek_char_next (dm) == 'U')
+ {
+ char buf[10];
+ int pos = 0;
+ advance_char (dm); advance_char (dm); length -= 2;
+ while (length-- > 0)
+ {
+ ch = next_char (dm);
+ if (!isxdigit (ch))
+ break;
+ buf[pos++] = ch;
+ }
+ if (ch != '_' || length < 0)
+ return STATUS_ERROR;
+ if (pos == 0)
+ {
+ /* __U_ just means __U. */
+ if (!dyn_string_append_cstr (identifier, "__U"))
+ return STATUS_ALLOCATION_FAILED;
+ continue;
+ }
+ else
+ {
+ buf[pos] = '\0';
+ ch = strtol (buf, 0, 16);
+ }
+ }
+
+ if (!dyn_string_append_char (identifier, ch))