Hi Tim,
> Not sure if the compiler is correct here, but maybe worth a look:
>
> hash.c:549:11: error: implicit conversion from 'unsigned long' to
> 'float' changes value from 18446744073709551615 to 18446744073709551616
> [-Werror,-Wimplicit-int-float-conversion]
> if (SIZE_MAX <= new_candidate)
> ^~~~~~~~ ~~
> /usr/include/stdint.h:227:22: note: expanded from macro 'SIZE_MAX'
> # define SIZE_MAX (18446744073709551615UL)
> ^~~~~~~~~~~~~~~~~~~~~~
This warning is pointless, because
- Since the next float below 18446744073709551616 = 0x10000000000000000
would be 18446742974197923840 = 0xFFFFFF0000000000
the comparison result is the same for the two values ...615 and ...616.
- The compiler inserts the implicit conversion only because of the '<='
operator.
IMO you should file a ticket with the clang people.
Inserting a cast to 'double'
if ((double) SIZE_MAX <= (double) new_candidate)
would not help, because
the next double-float below 18446744073709551616 = 0x10000000000000000
would be 18446744073709549568 = 0xFFFFFFFFFFFFF800
Bruno
