From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Forbes Subject: [PATCH 2/3] evaluate: warn on identical exprs around '||' Date: Sun, 28 Aug 2011 10:26:54 +1200 Message-ID: <1314484015-7694-2-git-send-email-chrisf@ijw.co.nz> References: <1314484015-7694-1-git-send-email-chrisf@ijw.co.nz> Return-path: Received: from mail-pz0-f42.google.com ([209.85.210.42]:46246 "EHLO mail-pz0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751718Ab1H0W1S (ORCPT ); Sat, 27 Aug 2011 18:27:18 -0400 Received: by mail-pz0-f42.google.com with SMTP id 37so6264861pzk.1 for ; Sat, 27 Aug 2011 15:27:18 -0700 (PDT) In-Reply-To: <1314484015-7694-1-git-send-email-chrisf@ijw.co.nz> Sender: linux-sparse-owner@vger.kernel.org List-Id: linux-sparse@vger.kernel.org To: linux-sparse@vger.kernel.org Cc: Chris Forbes Same as prev, but for || operator. Signed-off-by: Chris Forbes --- evaluate.c | 4 ++++ validation/check_identical_exprs_on_or.c | 24 ++++++++++++++++++++++++ 2 files changed, 28 insertions(+), 0 deletions(-) create mode 100644 validation/check_identical_exprs_on_or.c diff --git a/evaluate.c b/evaluate.c index 08f6ae6..11de7aa 100644 --- a/evaluate.c +++ b/evaluate.c @@ -985,6 +985,10 @@ static struct symbol *evaluate_logical(struct expression *expr) expr_equiv(expr->left, expr->right)) { warning(expr->pos, "identical expressions on both " "sides of '&&'"); + } else if (expr->op == SPECIAL_LOGICAL_OR && + expr_equiv(expr->left, expr->right)) { + warning(expr->pos, "identical expressions on both " + "sides of '||'"); } } diff --git a/validation/check_identical_exprs_on_or.c b/validation/check_identical_exprs_on_or.c new file mode 100644 index 0000000..74fe226 --- /dev/null +++ b/validation/check_identical_exprs_on_or.c @@ -0,0 +1,24 @@ +extern void bar(void); + +static void foo(void *a, void *b, void *c) +{ + if (a || a) /* should warn */ + bar(); + + if (a || b) /* should not warn */ + bar(); + + if ((a == b) || (a == b)) /* should warn */ + bar(); + + if ((a == b) || (b == c)) /* should not warn */ + bar(); +} +/* + * check-name: A warning should be issued for identical expressions on both sides of the '||' operator. + * + * check-error-start +check_identical_exprs_on_or.c:5:15: warning: identical expressions on both sides of '||' +check_identical_exprs_on_or.c:11:22: warning: identical expressions on both sides of '||' + * check-error-end + */ -- 1.7.4.1