mystrncat.c: (in function func)
mystrncat.c:12:13: Passed storage buffer not completely defined (*buffer is
                      undefined): mystrncat (buffer, ...)
mystrncat.c:13:13: Passed storage b not completely defined (*b is undefined):
                      mystrncat (b, ...)
mystrncat.c:13:3: Unresolved constraint:
    Lclint is unable to resolve Requires: :
    MAXREAD ((malloc(256) @ mystrncat.c:10:7 ) )  <=  ( 0 )  needed to satisfy
    Requires: : MAXSET ((b @ mystrncat.c:13:13 ) )  >=  (MAXREAD ((b @
    mystrncat.c:13:13 ) )) + (( 255 ) ) derived from mystrncat precondition:
    Requires: : MAXSET ((<parameter 1> ) )  >=  (MAXREAD ((<parameter 1> ) )) +
    ((<parameter 3> ) )
mystrncat.c:12:3: Unresolved constraint:
    Lclint is unable to resolve Requires: : MAXREAD ((buffer @
    mystrncat.c:12:13 ) )  <=  ( 0 )  needed to satisfy Requires: :
    MAXSET ((buffer @ mystrncat.c:12:13 ) )  >=  (MAXREAD ((buffer @
    mystrncat.c:12:13 ) )) + (( 255 ) ) derived from mystrncat precondition:
    Requires: : MAXSET ((<parameter 1> ) )  >=  (MAXREAD ((<parameter 1> ) )) +
    ((<parameter 3> ) )

Finished LCLint checking --- 4 code errors found, as expected