From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 7F81E3858413; Tue, 30 Jan 2024 11:55:56 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7F81E3858413 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1706615756; bh=dcm85l4SrooLiSDHobbC4pONlxJWu3Xl3h2Za8B5xPs=; h=From:To:Subject:Date:In-Reply-To:References:From; b=XMyBWsKbbiyDTXzMLwNpIgZom8KLWpbYK3DpWJSXkWHSpRptkIksmFdLrQW3qA4P/ 2v9i71LZ4v46U3XglA1pDeq0dOX6CfG6d45wCk1adVAR++0yIWUgPWO9qGNd6YntQp w9r4mVwZ8WoPiq1w5JGNylhsYtNTXngSAJNE7sMQ= From: "fweimer at redhat dot com" To: glibc-bugs@sourceware.org Subject: [Bug build/31316] Fails test misc/tst-dirname "Didn't expect signal from child: got `Illegal instruction'" on non SSE CPUs Date: Tue, 30 Jan 2024 11:55:54 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: build X-Bugzilla-Version: 2.38 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: fweimer at redhat dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D31316 Florian Weimer changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |fweimer at redhat dot com --- Comment #1 from Florian Weimer --- The instruction stream does not make sense. Running this: =E2=80=9C import base64 data=3D"""8d 70 08 f7 c6 0f 00 00 00 0f 85 20 0a 00 00 8d 5c 97 04 65 a1 0c 00 00 00 85 c0 0f 85 46 04 00 00 8b 4c 24 18 89 f0 c1 e8 0c 8b 79 = 08 8b 4c 24 14 31 f8 89 41 04 8b 44 24 18 8b 40 04 89 44 24 """.replace(' ', '').replace('\n', '') with open('f', 'wb') as out: out.write(base64.b16decode(data, casefold=3DTrue)) =E2=80=9D And: objdump -b binary -m i386 -D f gives: 0: 8d 70 08 lea 0x8(%eax),%esi 3: f7 c6 0f 00 00 00 test $0xf,%esi 9: 0f 85 20 0a 00 00 jne 0xa2f f: 8d 5c 97 04 lea 0x4(%edi,%edx,4),%ebx 13: 65 a1 0c 00 00 00 mov %gs:0xc,%eax 19: 85 c0 test %eax,%eax 1b: 0f 85 46 04 00 00 jne 0x467 21: 8b 4c 24 18 mov 0x18(%esp),%ecx 25: 89 f0 mov %esi,%eax 27: c1 e8 0c shr $0xc,%eax 2a: 8b 79 08 mov 0x8(%ecx),%edi 2d: 8b 4c 24 14 mov 0x14(%esp),%ecx 31: 31 f8 xor %edi,%eax 33: 89 41 04 mov %eax,0x4(%ecx) 36: 8b 44 24 18 mov 0x18(%esp),%eax 3a: 8b 40 04 mov 0x4(%eax),%eax 3d: 89 .byte 0x89 3e: 44 inc %esp 3f: 24 .byte 0x24 The fault is at offset 0x2a, which is as far as I can see a perfectly fine = i386 instruction. It's also not in a string function, the instruction sequence involving %gs is related to a single-thread optimization. The tail involving inc %esp is also really dubious. Could you obtain a backtrace using GDB, possibly from a coredump? --=20 You are receiving this mail because: You are on the CC list for the bug.=