Found the following significant warnings:
  divsub.c:59:49: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:59:63: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:570:94: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:576:73: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:577:41: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:577:58: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:629:64: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:630:19: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:665:12: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:665:43: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:695:51: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:695:61: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:715:29: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  divsub.c:716:48: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:36:9: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:59:43: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:59:57: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:68:43: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:68:49: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:68:63: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:71:31: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:71:45: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:87:13: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:104:11: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:104:20: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:120:85: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:121:37: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:122:22: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:123:17: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:124:36: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:124:51: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:124:73: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:124:75: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:125:12: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:126:38: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:128:53: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:129:53: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:131:11: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:131:38: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:158:9: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:169:35: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:178:49: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:178:72: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:257:43: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:257:51: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:257:57: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:258:50: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:258:59: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  phylog.c:258:65: warning: invalid UTF-8 in comment [-Winvalid-utf8]
  testamova.c:116:22: warning: invalid UTF-8 in comment [-Winvalid-utf8]
See '/home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/ade4.Rcheck/00install.out' for details.