From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id A3A0A3858410 for ; Thu, 9 May 2024 17:42:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org A3A0A3858410 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org A3A0A3858410 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1715276576; cv=none; b=K3ykCUCMtJ63+dk2B+1oUdcKwXE2L5hAmhMlhvNEfv2CUffDvLIvoJ2iphqlqbOxa6tVKghSBjncdFIrdTNoIc4GIQ2mF7mMdqnt8rJeDZqihVVjmk+okt94TMK64eIxrE2CLOpaXPM21GfASMc0Il7gdlWhdL7discyZddysMg= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1715276576; c=relaxed/simple; bh=hzBVqMJXqLi2bh4TfRJ0Y5LqPiaRyGIB/XCh0L9VTdg=; h=DKIM-Signature:From:To:Subject:Date:Message-Id:MIME-Version; b=DCCb/x5J8+AlnUMIrHK9+kMKqr50m/GcKidwUgb6SWFOCBcu6tK9xBRVEBAIaR0MyTrAdMaYE3PKwNcRkSq/9ziYOmk7AfTVziYX76Fc42ibgYKCAXZWcCpUxOApKdWaqKJP60fq/b29a/p8UgdBGuzkC5fQtXApbR+RWvblDOc= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1715276572; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=kHyu4C8HeEOS0Z1K+7QKrMat5xPK4/nkC8fNh1mt+TQ=; b=NYSyi8LAJU2ogJv+alRxcWD0ll6u/p96k1D8zzcala93foAL2WJcTibfaEk7HIscLee7aq l7wYWJvmyuqy+llvkhumgtndbVtx3VGgjqnNzWa+y3VvySg3EH8xQ6LhI34Zefi+scu8/+ i+WWZ+tLF8n47ebuxcjbhZ2Ih0b2ZS8= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-185-SoD7WVjeOnaphHXLsV4xlQ-1; Thu, 09 May 2024 13:42:50 -0400 X-MC-Unique: SoD7WVjeOnaphHXLsV4xlQ-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A6B10800CA5 for ; Thu, 9 May 2024 17:42:50 +0000 (UTC) Received: from t14s.localdomain.com (unknown [10.22.18.2]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7EA3B746821; Thu, 9 May 2024 17:42:50 +0000 (UTC) From: David Malcolm To: gcc-patches@gcc.gnu.org Cc: David Malcolm Subject: [PATCH 12/21] analyzer: casting all zeroes should give all zeroes [PR113333] Date: Thu, 9 May 2024 13:42:27 -0400 Message-Id: <20240509174236.2278921-13-dmalcolm@redhat.com> In-Reply-To: <20240509174236.2278921-1-dmalcolm@redhat.com> References: <20240509174236.2278921-1-dmalcolm@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true X-Spam-Status: No, score=-11.7 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: In particular, accessing the result of *calloc (1, SZ) (if non-NULL) should be known to be all zeroes. (backported from commit r14-7265-gd235bf2e807c5f) gcc/analyzer/ChangeLog: PR analyzer/113333 * region-model-manager.cc (region_model_manager::maybe_fold_unaryop): Casting all zeroes should give all zeroes. gcc/testsuite/ChangeLog: PR analyzer/113333 * gcc.dg/analyzer/calloc-1.c: Add tests. * gcc.dg/analyzer/data-model-9.c: Update expected results. * gcc.dg/analyzer/pr96639.c: Update expected results. Signed-off-by: David Malcolm --- gcc/analyzer/region-model-manager.cc | 6 ++++ gcc/testsuite/gcc.dg/analyzer/calloc-1.c | 34 ++++++++++++++++++++ gcc/testsuite/gcc.dg/analyzer/data-model-9.c | 6 ++-- gcc/testsuite/gcc.dg/analyzer/pr96639.c | 2 +- 4 files changed, 43 insertions(+), 5 deletions(-) diff --git a/gcc/analyzer/region-model-manager.cc b/gcc/analyzer/region-model-manager.cc index 1a9886fd83c..51a2d8b029f 100644 --- a/gcc/analyzer/region-model-manager.cc +++ b/gcc/analyzer/region-model-manager.cc @@ -422,6 +422,12 @@ region_model_manager::maybe_fold_unaryop (tree type, enum tree_code op, && region_sval->get_type () && POINTER_TYPE_P (region_sval->get_type ())) return get_ptr_svalue (type, region_sval->get_pointee ()); + + /* Casting all zeroes should give all zeroes. */ + if (type + && arg->all_zeroes_p () + && (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))) + return get_or_create_int_cst (type, 0); } break; case TRUTH_NOT_EXPR: diff --git a/gcc/testsuite/gcc.dg/analyzer/calloc-1.c b/gcc/testsuite/gcc.dg/analyzer/calloc-1.c index bc28128671f..efb1a24c96a 100644 --- a/gcc/testsuite/gcc.dg/analyzer/calloc-1.c +++ b/gcc/testsuite/gcc.dg/analyzer/calloc-1.c @@ -25,3 +25,37 @@ char *test_1 (size_t sz) return p; } + +char ** +test_pr113333_1 (void) +{ + char **p = (char **)calloc (1, sizeof(char *)); + if (p) + { + __analyzer_eval (*p == 0); /* { dg-warning "TRUE" } */ + __analyzer_eval (p[0] == 0); /* { dg-warning "TRUE" } */ + } + return p; +} + +char ** +test_pr113333_2 (void) +{ + char **p = (char **)calloc (2, sizeof(char *)); + if (p) + { + __analyzer_eval (*p == 0); /* { dg-warning "TRUE" } */ + __analyzer_eval (p[0] == 0); /* { dg-warning "TRUE" } */ + __analyzer_eval (p[1] == 0); /* { dg-warning "TRUE" } */ + } + return p; +} + +char ** +test_pr113333_3 (void) +{ + char **vec = (char **)calloc (1, sizeof(char *)); + if (vec) + for (char **p=vec ; *p ; p++); /* { dg-bogus "heap-based buffer over-read" } */ + return vec; +} diff --git a/gcc/testsuite/gcc.dg/analyzer/data-model-9.c b/gcc/testsuite/gcc.dg/analyzer/data-model-9.c index 159bc612576..2121f20c4f0 100644 --- a/gcc/testsuite/gcc.dg/analyzer/data-model-9.c +++ b/gcc/testsuite/gcc.dg/analyzer/data-model-9.c @@ -14,8 +14,7 @@ void test_1 (void) struct foo *f = calloc (1, sizeof (struct foo)); if (f == NULL) return; - __analyzer_eval (f->i == 0); /* { dg-warning "TRUE" "desired" { xfail *-*-* } } */ - /* { dg-bogus "UNKNOWN" "status quo" { xfail *-*-* } .-1 } */ + __analyzer_eval (f->i == 0); /* { dg-warning "TRUE" } */ free (f); } @@ -27,7 +26,6 @@ void test_2 (void) if (f == NULL) return; memset (f, 0, sizeof (struct foo)); - __analyzer_eval (f->i == 0); /* { dg-warning "TRUE" "desired" { xfail *-*-* } } */ - /* { dg-bogus "UNKNOWN" "status quo" { xfail *-*-* } .-1 } */ + __analyzer_eval (f->i == 0); /* { dg-warning "TRUE" } */ free (f); } diff --git a/gcc/testsuite/gcc.dg/analyzer/pr96639.c b/gcc/testsuite/gcc.dg/analyzer/pr96639.c index aedf0464dc9..c06a5c02f79 100644 --- a/gcc/testsuite/gcc.dg/analyzer/pr96639.c +++ b/gcc/testsuite/gcc.dg/analyzer/pr96639.c @@ -6,5 +6,5 @@ x7 (void) int **md = calloc (1, sizeof (void *)); return md[0][0]; /* { dg-warning "possibly-NULL" "unchecked deref" } */ - /* { dg-warning "leak of 'md'" "leak" { target *-*-* } .-1 } */ + /* { dg-warning "Wanalyzer-null-dereference" "deref of NULL" { target *-*-* } .-1 } */ } -- 2.26.3