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bh=OWJ4yaWNjxPu2ysbgj55qVygT7d6hyH6ePcO7QutRko=; b=KLhFkPs5U5LKqhd1jyQQ+xy7jO1oE4Cr7ZRHLqKhQraFKhJBLwK5Z/uH/AQ0HLa7oQaI9z GIOOjyh/N9tmvMUgqlHVI29b6XDayzwtsnakS9ARWEuM4FuuNo6i1YYtjK3+kwDOQjlNI/ dy9gE+c7n7H3zS92plOi9iy2kbeMi0k= Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2022-7-12 header.b=DCbMT1ud; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=cBSNHMnx; arc=pass ("microsoft.com:s=arcselector9901:i=1"); spf=none (imf11.hostedemail.com: domain of dan.carpenter@oracle.com has no SPF policy when checking 205.220.165.32) smtp.mailfrom=dan.carpenter@oracle.com; dmarc=pass (policy=none) header.from=oracle.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 2340F40020 X-Stat-Signature: ikk95je3tot4484c8u9te8qas1qsyjnc X-Rspam-User: X-HE-Tag: 1658469054-957033 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Jul 21, 2022 at 10:52:54AM -0700, Mike Kravetz wrote: > > diff --git a/tools/testing/selftests/vm/hugetlb-madvise.c b/tools/testing/selftests/vm/hugetlb-madvise.c > > index 6c6af40f5747..3c9943131881 100644 > > --- a/tools/testing/selftests/vm/hugetlb-madvise.c > > +++ b/tools/testing/selftests/vm/hugetlb-madvise.c > > @@ -89,10 +89,11 @@ void write_fault_pages(void *addr, unsigned long nr_pages) > > > > void read_fault_pages(void *addr, unsigned long nr_pages) > > { > > - unsigned long i, tmp; > > + unsigned long dummy = 0; > > + unsigned long i; > > > > for (i = 0; i < nr_pages; i++) > > - tmp += *((unsigned long *)(addr + (i * huge_page_size))); > > When I originally wrote this, something must have complained if written as: > > tmp = *((unsigned long *)(addr + (i * huge_page_size))); > > changing to += eliminated that complaint, but caused this one. Happy > with your changes, but if there is an even better way to write this, I am > happy to change it. These days compilers don't like when you read something and then don't use it. It's possible they might just start optimizing parts of that away? I think we've now tricked the compiler into doing what we want. regards, dan carpenter