Found the following significant warnings:
  ./Rmpi.h:34:20: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:35:18: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:36:28: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:37:23: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:38:20: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:39:17: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:40:19: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:41:19: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:47:22: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:49:24: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:51:25: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  ./Rmpi.h:89:19: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:38:13: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:60:20: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:110:18: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:121:29: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:142:23: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:153:20: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:157:17: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:161:19: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:165:19: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:208:22: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:221:24: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:235:25: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  Rmpi.c:1068:19: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
  conversion.c:31:9: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
See ‘/data/gannet/ripley/R/packages/tests-clang/Rmpi.Rcheck/00install.out’ for details.
* used C compiler: ‘clang version 15.0.6’