tests/qht-bench.c:287:29: error: implicit conversion from 'unsigned long' to 'double' changes value from 18446744073709551615 to 18446744073709551616 [-Werror,-Wimplicit-int-float-conversion] *threshold = rate * UINT64_MAX; ~ ^~~~~~~~~~
Fix this by splitting the 64-bit constant into two halves, each of which is individually perfectly representable, the sum of which produces the correct arithmetic result. Cc: Emilio G. Cota <c...@braap.org> Reported-by: Philippe Mathieu-Daudé <phi...@redhat.com> Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- Question: Should we really be scaling by UINT64_MAX? The comparisons against info->r mean that 1.0 is exceedingly unlikely to hit. Or if that is supposed to be the point, why is is the test r >= threshold not r > threshold where, if threshold == UINT64_MAX, there is zero chance of the test being true for 1.0. --- tests/qht-bench.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tests/qht-bench.c b/tests/qht-bench.c index e3b512f26f..eb88a90137 100644 --- a/tests/qht-bench.c +++ b/tests/qht-bench.c @@ -284,7 +284,8 @@ static void do_threshold(double rate, uint64_t *threshold) if (rate == 1.0) { *threshold = UINT64_MAX; } else { - *threshold = rate * UINT64_MAX; + *threshold = (rate * 0xffff000000000000ull) + + (rate * 0x0000ffffffffffffull); } } -- 2.25.1