Found the following significant warnings:
  fastcodes.cpp:152:8: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:152:33: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:152:59: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:152:84: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:155:15: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:155:40: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:155:66: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:155:91: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:645:8: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:645:33: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:645:59: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:645:84: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:648:15: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:648:40: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:648:66: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
  fastcodes.cpp:648:91: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
See '/home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/combinIT.Rcheck/00install.out' for details.