On 6/17/20 6:37 AM, Richard Henderson wrote:
> From: Wei Wang
>
> It's reported an error of implicit conversion from "unsigned long" to
> "double" when compiling with Clang 10. Simply make the encoding rate 0
> when the encoded_size is 0.
There is a similar error in tests/qht-bench.c, see the asan log:
https://patchew.org/QEMU/20200617072539.32686-1-f4...@amsat.org/
/tmp/qemu-test/src/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;
~ ^~
/usr/include/stdint.h:130:23: note: expanded from macro 'UINT64_MAX'
# define UINT64_MAX (__UINT64_C(18446744073709551615))
^~~~
/usr/include/stdint.h:107:25: note: expanded from macro '__UINT64_C'
# define __UINT64_C(c) c ## UL
^~~
:33:1: note: expanded from here
18446744073709551615UL
^~
1 error generated.
make: *** [/tmp/qemu-test/src/rules.mak:69: tests/qht-bench.o] Error 1
>
> Fixes: e460a4b1a4
> Reviewed-by: Dr. David Alan Gilbert
> Reviewed-by: Richard Henderson
> Reported-by: Richard Henderson
> Signed-off-by: Wei Wang
> Signed-off-by: Richard Henderson
> ---
> migration/ram.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index 41cc530d9d..069b6e30bc 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -913,10 +913,8 @@ static void migration_update_rates(RAMState *rs, int64_t
> end_time)
> unencoded_size = (xbzrle_counters.pages - rs->xbzrle_pages_prev) *
> TARGET_PAGE_SIZE;
> encoded_size = xbzrle_counters.bytes - rs->xbzrle_bytes_prev;
> -if (xbzrle_counters.pages == rs->xbzrle_pages_prev) {
> +if (xbzrle_counters.pages == rs->xbzrle_pages_prev || !encoded_size)
> {
> xbzrle_counters.encoding_rate = 0;
> -} else if (!encoded_size) {
> -xbzrle_counters.encoding_rate = UINT64_MAX;
> } else {
> xbzrle_counters.encoding_rate = unencoded_size / encoded_size;
> }
>
