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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: CH2PR10MB4344.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: bdd157d7-2c53-42a5-0a95-08dad6d44a2e X-MS-Exchange-CrossTenant-originalarrivaltime: 05 Dec 2022 15:20:49.1662 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: HedpjNCyvQRMwAaBvKL6Mp19ZN0jICvB2OmLa1191mi9ofCB2S8aWhD4/PNGAC4Dh9ILPipDN4xVhomEyMhTWw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR10MB4909 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.923,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-12-05_01,2022-12-05_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 bulkscore=0 mlxlogscore=999 adultscore=0 malwarescore=0 spamscore=0 phishscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2212050126 X-Proofpoint-ORIG-GUID: UNFal_Z225mj3Ut3VWl6lY-JCCjFwHlU X-Proofpoint-GUID: UNFal_Z225mj3Ut3VWl6lY-JCCjFwHlU X-Spam-Status: No, score=-5.3 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,RCVD_IN_MSPIKE_H2,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: > On Dec 5, 2022, at 10:16 AM, Richard Biener wrote: >=20 > On Fri, 2 Dec 2022, Qing Zhao wrote: >=20 >>=20 >>=20 >>> On Dec 2, 2022, at 2:20 AM, Richard Biener wrote: >>>=20 >>> On Fri, 2 Dec 2022, Richard Biener wrote: >>>=20 >>>> On Thu, 1 Dec 2022, Siddhesh Poyarekar wrote: >>>>=20 >>>>> On 2022-12-01 11:42, Kees Cook wrote: >>>>>> On Wed, Nov 30, 2022 at 02:25:56PM +0000, Qing Zhao wrote: >>>>>>> '-Wstrict-flex-arrays' >>>>>>> Warn about inproper usages of flexible array members according = to >>>>>>> the LEVEL of the 'strict_flex_array (LEVEL)' attribute attached= to >>>>>>> the trailing array field of a structure if it's available, >>>>>>> otherwise according to the LEVEL of the option >>>>>>> '-fstrict-flex-arrays=3DLEVEL'. >>>>>>>=20 >>>>>>> This option is effective only when LEVEL is bigger than 0. >>>>>>> Otherwise, it will be ignored with a warning. >>>>>>>=20 >>>>>>> when LEVEL=3D1, warnings will be issued for a trailing array >>>>>>> reference of a structure that have 2 or more elements if the >>>>>>> trailing array is referenced as a flexible array member. >>>>>>>=20 >>>>>>> when LEVEL=3D2, in addition to LEVEL=3D1, additional warnings w= ill be >>>>>>> issued for a trailing one-element array reference of a structur= e if >>>>>>> the array is referenced as a flexible array member. >>>>>>>=20 >>>>>>> when LEVEL=3D3, in addition to LEVEL=3D2, additional warnings w= ill be >>>>>>> issued for a trailing zero-length array reference of a structur= e if >>>>>>> the array is referenced as a flexible array member. >>>>>>>=20 >>>>>>> At the same time, -Warray-bounds is updated: >>>>>>=20 >>>>>> Why is there both -Wstrict-flex-arrays and -Warray-bounds? I thought >>>>>> only the latter was going to exist? >>>>=20 >>>> Sorry for appearantly not being clear - I was requesting=20 >>>> -Wstrict-flex-arrays to be dropped and instead adjusting -Warray-bound= s >>>> to adhere to -fstrict-flex-arrays in both =3D1 and =3D2 where then =3D= 2 >>>> would only add the intermediate pointer results verification. >>>>=20 >>>> I think that's reasonable if documented since the default behavior >>>> with -Wall will not change then unless the -fstrict-flex-arrays >>>> default is altered. >>>=20 >>> Btw, your patch seems to implement the above plus adds=20 >>> -Wstrict-flex-arrays. It seems it could be split into two, doing >>> the -Warray-bounds adjustment as first and the -Wstrict-flex-arrays=20 >>> addition as second. >>=20 >> Yes, implementation should be very easy to be adjusted to drop the new -= Wstrict-flex-arrays option. >> But I still feel the new -Wstrict-flex-arrays option is good to add. >=20 > Can you split the patch and re-post? I'll quickly approve the first > part and will think harder on the second. Okay, I will do that. thanks. Qing >=20 > Thanks, > Richard. >=20 >> Qing >>> We do all seem to agree on the first so it's easy >>> to go forward with that? >>>=20 >>> Thanks, >>> Richard. >>=20 >>=20 >=20 > --=20 > Richard Biener > SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg= , > Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman; > HRB 36809 (AG Nuernberg)