Found the following significant warnings:
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/libgeos/include/libgeos.h:46:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/libgeos/include/libgeos.h:434:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/wk/include/wk-v1.h:101:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/wk/include/wk-v1.h:106:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:179:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:181:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:182:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:183:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:380:6: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:394:6: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  init.c:401:6: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/libgeos/include/libgeos.c:8:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/libgeos/include/libgeos.c:262:6: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/libgeos/include/libgeos.c:263:3: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/wk/include/wk-v1-impl.c:50:15: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/wk/include/wk-v1-impl.c:148:13: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
See ‘/home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/geos.Rcheck/00install.out’ for details.