From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by sourceware.org (Postfix) with ESMTPS id 0ECD93858D1E for ; Sat, 11 Nov 2023 03:07:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 0ECD93858D1E Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 0ECD93858D1E Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2607:f8b0:4864:20::52f ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1699672074; cv=none; b=SCa7Ey4X1JOl/qB+nK16S8m5PP0g1+OdkeLmjErYox4a9O3RrYWYrIXcIm+Kv6CwV2zpoGDts0qBmcyE2QevOXXi0cVwj7HZqVcrBVjS1sbWF1T/y79hFWG2lhSkw19Ys/reIa6rvrcrd7uyOlYsZHgJUZ6vodjfpSs1LPDZZVk= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1699672074; c=relaxed/simple; bh=p5kd3395hi2/58PsM98E3tGHIXsMqgZPQgAT0OM9D84=; h=DKIM-Signature:MIME-Version:From:Date:Message-ID:Subject:To; b=SVci8dWrNt1HqpW0zKj+H+R1d27eGvUAY5wxiK/nimOkn/KcuUaq/dCKexe5wA8AZAoU/RpqYsImhcpZGIftd2a3e1e9QvNtyqf94By6mMDmB+MZoae+GzYuSoGx3l5/E640Bp0BJpOJXbwHQG7Q/JTbCYSW8J/KBQSgI2lJyc0= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-pg1-x52f.google.com with SMTP id 41be03b00d2f7-5bdc18756a3so1913799a12.1 for ; Fri, 10 Nov 2023 19:07:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1699672070; x=1700276870; darn=sourceware.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=Tsnl52zgBV+SYNNY6QIVvF/V8O7rr+tH38CdOPMsFU0=; b=NNNJFUI8hktGZ7OAqvARxfVyUQMnw3fvo22bSg6YlgNTRzCL0Fgfak59Nu7iRBF5GG GKCBw5asmXYZ8165nFbkk8oVeHq97YEyqxiVlOLHQrqeeztYenzD93qQrLIjj7y+JvBN aI+zXXlxhYR9eMzE9rQqhz7CR7GvdKfnQOBYRUeEcGFzVXwDZn0QfKQBkN1ofh1Qy1vY JopvhXlwwSIsKX/fz2VvhzcpU4JPAIRotO0J7gVp3x36zKiJBRnNW5Rfhwjp/R0Wy38m G65DeXtJhSuUsrT7FyNJT46TfltegDnNlOfJpR+oRsLEcjiBUYY25hLsxscFravMV2Sr rqOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699672070; x=1700276870; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Tsnl52zgBV+SYNNY6QIVvF/V8O7rr+tH38CdOPMsFU0=; b=WSud6h63Wd8fU+LTfvTXkBYQj1UB/ERPYpfS/G71GZ5B1WIuKVro8s8sBhypt8pLvP dygqEbTlNruSbE7Xf1lddHSKEjZl3w1hNVwis+3D5RyWxjMQ3IkoSvf9k4PUGzjROpZf 0Q+8ZFldD30lZSSCdKcVrxrqdAXWN7vOavhu2nYDm+QN5fj6t4BB51dUvG0FC2CR9qZ5 MoPjVOyWk0rufY8RjIrX+aMopgo78F0PlGrM2yZEurk8Xi5x7Xk9tFJtDWgTu5wq8KtM crn6Tn4XYawpmjs1+7jvsMm6RhYGo/WHODPDDzyIpVwOCuNwClaoHtYWA7zbZ9O5UCgj t0oA== X-Gm-Message-State: AOJu0YyM6mD69YME8ERpeBVTSPwixjD1NUk+ntYQf7X8oorA/wifXx/3 zeVpkjKcMHx0fQPB3OJmihToRUiOYgl20aKaVfWbTD/4 X-Google-Smtp-Source: AGHT+IHc/O6ZtyReDyS5b2CQMP3TgNezApDnAvYdyyyWGqR+RsaAzL9Z1MK+m7UP0TSZydILoqHcYuA8ZjA7jmCzZBA= X-Received: by 2002:a05:6a20:7343:b0:181:6f91:efe with SMTP id v3-20020a056a20734300b001816f910efemr953291pzc.19.1699672070206; Fri, 10 Nov 2023 19:07:50 -0800 (PST) MIME-Version: 1.0 References: <877cnd4qy8.fsf@redhat.com> In-Reply-To: From: Zeck S Date: Fri, 10 Nov 2023 21:07:28 -0600 Message-ID: Subject: Re: [RFC][PATCH?] fixed some segfaults and bugs in mdebug support To: Andrew Burgess Cc: gdb-patches@sourceware.org Content-Type: multipart/alternative; boundary="000000000000faba3e0609d7bde9" X-Spam-Status: No, score=-9.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,GIT_PATCH_0,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE 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: --000000000000faba3e0609d7bde9 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable I'm still working on the testing. Been setting up QEMU stuff so I can run linux mips code. Seems like the best option. I think I should be able to get the test suite to call the IDO compiler and use the linux mips linker. Also, sent the signed paperwork to the FSF for copyright assignment, and am waiting to hear back. Been a few weeks, so, figured I'd post an update. Fixed one more small bug I found as well. On Mon, Oct 23, 2023 at 7:25=E2=80=AFPM Zeck S wrote: > Oh, I messed up the diff. Spoiled by github, never done it this way. > The testing makes sense now. Might be the weekend before I can make much > progress on that. > Thanks for the fast reply! > > On Mon, Oct 23, 2023 at 4:40=E2=80=AFAM Andrew Burgess > wrote: > >> Zeck S writes: >> >> > First off, I apologize if I'm doing this process wrong. I have sent an >> > email to assign@gnu.org trying to get the paperwork required for >> copyright >> > assignment. I think that's the correct thing to do? >> > >> > While I wait on that, I'm not sure exactly what is required for these >> > changes. >> > >> > Here's what I fixed in mdebug support. >> > >> > info sym funcName would segfault >> > The first problem was that no compunit_symtab was set for the >> global_block >> > on blockvectors in new_symtab. This caused a crash in block.c. >> > initialize_block_iterator called get_block_compunit_symtab and the >> > assertion gdb_assert (gb->compunit_symtab !=3D NULL); would fail. >> > >> > info types would segfault >> > The second problem was memory corruption. struct global_block is a >> larger >> > and different type from plain block and blockvector is expected to have >> > index 0 be a global_block struct. This can be seen done correctly in >> jit.c >> > near /* Now add the special blocks */ under if (i =3D=3D GLOBAL_BLOCK). >> Failing >> > to allocate this correctly leads to crashes for me (usually) in >> > set_compunit_symtab where the assertion gdb_assert >> (gb->compunit_symtab =3D=3D >> > NULL); would randomly fail. This fix is also in new_symtab. >> > >> > info line file:line did not work >> > The third problem was finding lines never worked because add_line never >> set >> > .is_stmt to true, so in symtab.c find_line_common never saw >> item->is_stmt >> > as true, do it always went down the /* Ignore non-statements. */ path = in >> > its main loop. >> >> I was confused by this description as the only change I see is you >> removing this line 'lt->item[lt->nitems].is_stmt =3D 1;' , but I suspect >> you generated your diff the wrong way round. >> >> You should consider creating your diff as a git commit, then use 'git >> send-email' to send out patches, I found this site >> https://git-send-email.io/ a pretty useful guide for setting up git & >> email sending. >> >> > >> > I looked in the gdb/testsuite directory, and I don't see a directory f= or >> > mips or mdebug? Unsure how to set up a test for this. To make files wi= th >> > mdebug symbols, I used the old IRIX IDO compiler running under a kind = of >> > qemu setup used by N64 game reverse engineering projects. (N64 dev is >> why >> > I'm interested in this symbol format. I can connect vscode to gdb and >> gdb >> > to an n64 emulator with a gdb stub to debug with symbols) >> >> You might not need to add any new tests at all, IF you can identify some >> existing tests that are fixed by your changes. >> >> Most tests are not separated based on which compiler or environment is >> used, though clearly there are exceptions, e.g. gdb.arch/*.exp does >> contain some architecture specific tests. Instead most tests are >> written based on the GDB feature being tested. For example, >> gdb.base/infoline.exp tests the 'info line' command. >> >> The expectation is that if someone has a more niche compiler or >> environment then they will perform their own regression testing using >> their setup. >> >> So, hopefully, if you can get the GDB tests running using your >> toolchain, then without your patch you'll see some failures in (maybe) >> gdb.base/infoline.exp, and after your patch some of the failures would >> be resolved, you'd then mention some (or all) of these improvements in >> your commit message. >> >> Of course, if your particular situation isn't covered by an existing >> test then you might need to extend an existing test -- or create a new >> test -- whatever seems most appropriate. >> >> > >> > diff --git a/gdb/mdebugread.c b/gdb/mdebugread.c >> > index 4b0a1eb255f..9cb30ce0acd 100644 >> > --- a/gdb/mdebugread.c >> > +++ b/gdb/mdebugread.c >> > @@ -239,9 +239,6 @@ enum block_type { FUNCTION_BLOCK, >> NON_FUNCTION_BLOCK }; >> > static struct block *new_block (struct objfile *objfile, >> > enum block_type, enum language); >> > >> > -static struct block *new_global_block (struct objfile *objfile, >> > - enum block_type, enum language); >> > - >> > static struct compunit_symtab *new_symtab (const char *, int, struct >> > objfile *); >> > >> > static struct linetable *new_linetable (int); >> > @@ -4545,7 +4542,6 @@ add_line (struct linetable *lt, int lineno, >> CORE_ADDR >> > adr, int last) >> > return lineno; >> > >> > lt->item[lt->nitems].line =3D lineno; >> > - lt->item[lt->nitems].is_stmt =3D 1; >> > lt->item[lt->nitems++].set_unrelocated_pc (unrelocated_addr (adr << >> 2)); >> > return lineno; >> > } >> > @@ -4638,10 +4634,9 @@ new_symtab (const char *name, int maxlines, >> struct >> > objfile *objfile) >> > >> > /* All symtabs must have at least two blocks. */ >> > bv =3D new_bvect (2); >> > - bv->set_block (GLOBAL_BLOCK, new_global_block (objfile, >> > NON_FUNCTION_BLOCK, lang)); >> > + bv->set_block (GLOBAL_BLOCK, new_block (objfile, NON_FUNCTION_BLOCK, >> > lang)); >> > bv->set_block (STATIC_BLOCK, new_block (objfile, NON_FUNCTION_BLOCK, >> > lang)); >> > bv->static_block ()->set_superblock (bv->global_block ()); >> > - bv->global_block ()->set_compunit_symtab(cust); >> > cust->set_blockvector (bv); >> > >> > cust->set_debugformat ("ECOFF"); >> > @@ -4740,21 +4735,6 @@ new_block (struct objfile *objfile, enum >> block_type >> > type, >> > return retval; >> > } >> > >> > -static struct block * >> > -new_global_block (struct objfile *objfile, enum block_type type, >> > - enum language language) >> >> Static functions should have a comment before them. In this case >> something as simple as: >> >> /* Like new_block, but create a global_block. */ >> >> Though I wonder if we could/should just give new_block an extra >> parameter so its declaration becomes: >> >> static struct block *new_block (struct objfile *objfile, >> enum block_type, enum language, >> bool global_block =3D false); >> >> Hopefully it's obvious how the new parameter would be used :) >> >> Thanks, >> Andrew >> >> >> > -{ >> > - struct block *retval =3D new (&objfile->objfile_obstack) global_blo= ck; >> > - >> > - if (type =3D=3D FUNCTION_BLOCK) >> > - retval->set_multidict (mdict_create_linear_expandable (language)); >> > - else >> > - retval->set_multidict (mdict_create_hashed_expandable (language)); >> > - >> > - return retval; >> > -} >> > - >> > - >> > /* Create a new symbol with printname NAME. */ >> > >> > static struct symbol * >> >> --000000000000faba3e0609d7bde9--