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 [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 95F15385C6E5 for ; Thu, 30 Nov 2023 15:46:07 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 95F15385C6E5 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 95F15385C6E5 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701359169; cv=none; b=Ekmk7y/+qVz+uhd4Lhw+apI2FSHP97z2LcEyBfKdlMvtK8w5wcFclfqQbJtedQAHuMF/998liolt6yC8XY9v7ANHn52DZZuloah3ceQOiFz2d4sgzTrvTtgsxqRV5y7bw8oOw3aBDPMtC/IX2AEygQ80JdwL/9iIaRP+hQa3gXs= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701359169; c=relaxed/simple; bh=FTyMW5lGmIzrFAx5H2Vw8hiIXqi4QiZlBNg+sv1YExw=; h=DKIM-Signature:From:Date:To:Subject:Message-ID:MIME-Version; b=tOjbJnLTGoEQHbwwlEarTmpGLaWKJgx5f4+L4PmjTxGWTKZw7bQsf1SC3zYwxkBZC/ZfxG0uPee3MSSr9Duz5uUgCqliKmVE8NUSaSJ5qAZatfQ+mNX/cF8+/1XS/6FPX2Uswvyt9FPubHDXYxPPgdSd7kbEav5gB5WRt1NLRtg= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701359167; 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: in-reply-to:in-reply-to:references:references; bh=TLh/coTtg8Ma2AC+0bhjHD5gs2b0dXxsZ3XSInodb3g=; b=GReBqpVg6m1ALoDZPdY1niBlPVGSNz9e+Z3S9DYvbLFHbrdo9/i/MzO9vrU+Ro1iPzH13V xZPfmOlev+i2+QfSWKjOyBzBm9KO83WIQ2paH42eEyT3aMRJzDixVc4gp/SZPZ5aZazIsf 7GUtSo7T3GzfWAr+aWHLZwX8FXT07c4= Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-504-5heHmCqoPVKt_qbsHb0h5g-1; Thu, 30 Nov 2023 10:46:06 -0500 X-MC-Unique: 5heHmCqoPVKt_qbsHb0h5g-1 Received: by mail-qv1-f72.google.com with SMTP id 6a1803df08f44-67a903a9322so1532836d6.3 for ; Thu, 30 Nov 2023 07:46:04 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701359164; x=1701963964; h=mime-version:references:message-id:in-reply-to:subject:cc:to:date :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=vrSOor3ZXSzsf9A7Z8BacuWaKVr2iT/JH4bdxi/jGfQ=; b=vGRsBJOy8Xc3Erw8V79Zq9o7UWHZA1+s2IGPGHzp0RdvK6SRQha9L4Zh8UMFcBg2Ox WBxZYxGwYKX3lTmAK5I9951gEgb7FRMGH0J7SJAYAVzJeVEOMUlPbX4YkgevqFqUuCnX 6JM6Tv2Hp6uOeAJL3vXXz4EYz2wP4nJsHj2zOkHdkoHJBNy2mn3VfmHuN+789qjtDsVo ZmtJOhM1JskJd3R4kaz7hMHjPnjll4bYki3wfu1e0pwfoOPml72CJkMjKyYtwzjdiJi5 qQyEVvVk60dKtysShvgssPvTo1838DA0zz01j2nhZOtTeXkbogdHrsZk3sY1oknCNchV Wx1g== X-Gm-Message-State: AOJu0YyH/MuSWmjGcRDMW+krxjkck0DCUGIbOJm9pc9tHNUUYt0OREo0 R+onqQv4Tys51luTsQkCKtfSWg4GRZKdCFe8yvG/mjyV2iLl0kdnazYI5REuNwVOVQGwrjrcTBg zJoXtfKCFl850dgTQ0Q== X-Received: by 2002:a05:622a:2299:b0:423:9b25:3943 with SMTP id ay25-20020a05622a229900b004239b253943mr24457798qtb.65.1701359164402; Thu, 30 Nov 2023 07:46:04 -0800 (PST) X-Google-Smtp-Source: AGHT+IEJby6FJE6V4Bb+Z9tXE6FO/4jxnrldH1Dt/OwhtkLOjesQ0+TNuljQLDgoZ4MEz8HtnKlPgw== X-Received: by 2002:a05:622a:2299:b0:423:9b25:3943 with SMTP id ay25-20020a05622a229900b004239b253943mr24457774qtb.65.1701359163949; Thu, 30 Nov 2023 07:46:03 -0800 (PST) Received: from [192.168.1.130] (ool-457670bb.dyn.optonline.net. [69.118.112.187]) by smtp.gmail.com with ESMTPSA id h19-20020ac87453000000b00423aa7fdefbsm583996qtr.60.2023.11.30.07.46.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Nov 2023 07:46:03 -0800 (PST) From: Patrick Palka X-Google-Original-From: Patrick Palka Date: Thu, 30 Nov 2023 10:46:02 -0500 (EST) To: Patrick Palka cc: Jason Merrill , gcc-patches@gcc.gnu.org Subject: Re: [PATCH v3 3/3] c++: note other candidates when diagnosing deletedness In-Reply-To: <4ed7c5e7-6707-a679-aa83-d72736e0806a@idea> Message-ID: <3cfbf151-f87b-49bc-11a0-a96034f9eabb@idea> References: <20231027195532.2566822-1-ppalka@redhat.com> <20231027195532.2566822-3-ppalka@redhat.com> <35674d69-7c49-4b2d-99fb-977cf34e7e9a@redhat.com> <4ed7c5e7-6707-a679-aa83-d72736e0806a@idea> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/mixed; boundary="8323329-1479004300-1701359163=:41183" X-Spam-Status: No, score=-13.8 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_H3,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,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: This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-1479004300-1701359163=:41183 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT On Fri, 27 Oct 2023, Patrick Palka wrote: > On Fri, 27 Oct 2023, Jason Merrill wrote: > > > On 10/27/23 15:55, Patrick Palka wrote: > > > With the previous two patches in place, we can now extend our > > > deletedness diagnostic to note the other considered candidates, e.g.: > > > > > > deleted16.C: In function 'int main()': > > > deleted16.C:10:4: error: use of deleted function 'void f(int)' > > > 10 | f(0); > > > | ~^~~ > > > deleted16.C:5:6: note: declared here > > > 5 | void f(int) = delete; > > > | ^ > > > deleted16.C:5:6: note: candidate: 'void f(int)' (deleted) > > > deleted16.C:6:6: note: candidate: 'void f(...)' > > > 6 | void f(...); > > > | ^ > > > deleted16.C:7:6: note: candidate: 'void f(int, int)' > > > 7 | void f(int, int); > > > | ^ > > > deleted16.C:7:6: note: candidate expects 2 arguments, 1 provided > > > > > > These notes are controlled by a new command line flag -fnote-all-cands, > > > which also controls whether we note ignored candidates more generally. > > > > > > gcc/ChangeLog: > > > > > > * doc/invoke.texi (C++ Dialect Options): Document -fnote-all-cands. > > > > > > gcc/c-family/ChangeLog: > > > > > > * c.opt: Add -fnote-all-cands. > > > > > > gcc/cp/ChangeLog: > > > > > > * call.cc (print_z_candidates): Only print ignored candidates > > > when -fnote-all-cands is set. > > > (build_over_call): When diagnosing deletedness, call > > > print_z_candidates if -fnote-all-cands is set. > > > > My suggestion was also to suggest using the flag in cases where it would make > > a difference, e.g. > > > > note: some candidates omitted, use '-fnote-all-cands' to display them > > Ah thanks, fixed. That'll help a lot with discoverability of the flag. > > > > > Maybe "-fdiagnostics-all-candidates"? > > Nice, that's a better name indeed :) > > How does the following look? Full bootstrap/regtest in progress. > > Here's the output of e.g. deleted16a.C. I think I'd prefer to not print > the source line when emitting the suggestion, but I don't know how to do > that properly (aside from e.g. emitting the note at UNKNOWN_LOCATION). > > In file included from gcc/testsuite/g++.dg/cpp0x/deleted16a.C:4: > gcc/testsuite/g++.dg/cpp0x/deleted16.C: In function ‘int main()’: > gcc/testsuite/g++.dg/cpp0x/deleted16.C:21:4: error: use of deleted function ‘void f(int)’ > 21 | f(0); // { dg-error "deleted" } > | ~^~~ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:6:6: note: declared here > 6 | void f(int) = delete; // { dg-message "declared here" } > | ^ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:21:4: note: use ‘-fdiagnostics-all-candidates’ to display considered candidates > 21 | f(0); // { dg-error "deleted" } > | ~^~~ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:22:4: error: use of deleted function ‘void g(int)’ > 22 | g(0); // { dg-error "deleted" } > | ~^~~ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:12:6: note: declared here > 12 | void g(int) = delete; // { dg-message "declared here" } > | ^ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:22:4: note: use ‘-fdiagnostics-all-candidates’ to display considered candidates > 22 | g(0); // { dg-error "deleted" } > | ~^~~ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:23:4: error: use of deleted function ‘void h(T, T) [with T = int]’ > 23 | h(1, 1); // { dg-error "deleted" } > | ~^~~~~~ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:17:24: note: declared here > 17 | template void h(T, T) = delete; // { dg-message "declared here|candidate" } > | ^ > gcc/testsuite/g++.dg/cpp0x/deleted16.C:23:4: note: use ‘-fdiagnostics-all-candidates’ to display considered candidates > 23 | h(1, 1); // { dg-error "deleted" } > | ~^~~~~~ > > -- >8 -- > > > Subject: [PATCH 3/3] c++: note other candidates when diagnosing deletedness > > With the previous two patches in place, we can now extend our > deletedness diagnostic to note the other considered candidates, e.g.: > > deleted16.C: In function 'int main()': > deleted16.C:10:4: error: use of deleted function 'void f(int)' > 10 | f(0); > | ~^~~ > deleted16.C:5:6: note: declared here > 5 | void f(int) = delete; > | ^ > deleted16.C:5:6: note: candidate: 'void f(int)' (deleted) > deleted16.C:6:6: note: candidate: 'void f(...)' > 6 | void f(...); > | ^ > deleted16.C:7:6: note: candidate: 'void f(int, int)' > 7 | void f(int, int); > | ^ > deleted16.C:7:6: note: candidate expects 2 arguments, 1 provided > > These notes are controlled by a new command line flag > -fdiagnostics-all-candidates which also controls whether we note > ignored candidates more generally. > > gcc/ChangeLog: > > * doc/invoke.texi (C++ Dialect Options): Document > -fdiagnostics-all-candidates. > > gcc/c-family/ChangeLog: > > * c.opt: Add -fdiagnostics-all-candidates. > > gcc/cp/ChangeLog: > > * call.cc (print_z_candidates): Only print ignored candidates > when -fdiagnostics-all-candidates is set, otherwise suggest > the flag. > (build_over_call): When diagnosing deletedness, note > other candidates only if -fdiagnostics-all-candidates is > set, otherwise suggest the flag. > > gcc/testsuite/ChangeLog: > > * g++.dg/overload/error6.C: Pass -fdiagnostics-all-candidates. > * g++.dg/cpp0x/deleted16.C: New test. > * g++.dg/cpp0x/deleted16a.C: New test. > * g++.dg/overload/error6a.C: New test. Ping. > --- > gcc/c-family/c.opt | 4 ++++ > gcc/cp/call.cc | 19 ++++++++++++++++++- > gcc/doc/invoke.texi | 5 +++++ > gcc/testsuite/g++.dg/cpp0x/deleted16.C | 25 +++++++++++++++++++++++++ > gcc/testsuite/g++.dg/cpp0x/deleted16a.C | 12 ++++++++++++ > gcc/testsuite/g++.dg/overload/error6.C | 1 + > gcc/testsuite/g++.dg/overload/error6a.C | 6 ++++++ > 7 files changed, 71 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/g++.dg/cpp0x/deleted16.C > create mode 100644 gcc/testsuite/g++.dg/cpp0x/deleted16a.C > create mode 100644 gcc/testsuite/g++.dg/overload/error6a.C > > diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt > index 44b9c862c14..c12c86bb8ed 100644 > --- a/gcc/c-family/c.opt > +++ b/gcc/c-family/c.opt > @@ -1781,6 +1781,10 @@ fdiagnostics-show-template-tree > C++ ObjC++ Var(flag_diagnostics_show_template_tree) Init(0) > Print hierarchical comparisons when template types are mismatched. > > +fdiagnostics-all-candidates > +C++ ObjC++ Var(flag_diagnostics_all_candidates) > +Note all candidates during overload resolution failure. > + > fdirectives-only > C ObjC C++ ObjC++ > Preprocess directives only. > diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc > index 81cc029dddb..e9c099eedb8 100644 > --- a/gcc/cp/call.cc > +++ b/gcc/cp/call.cc > @@ -4090,6 +4090,12 @@ print_z_candidates (location_t loc, struct z_candidate *candidates, > { > if (only_viable_p.is_true () && candidates->viable != 1) > break; > + if (ignored_candidate_p (candidates) && !flag_diagnostics_all_candidates) > + { > + inform (loc, "some candidates omitted; " > + "use %<-fdiagnostics-all-candidates%> to display them"); > + break; > + } > print_z_candidate (loc, N_("candidate:"), candidates); > } > } > @@ -9933,7 +9939,18 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain) > if (DECL_DELETED_FN (fn)) > { > if (complain & tf_error) > - mark_used (fn); > + { > + mark_used (fn); > + if (cand->next) > + { > + if (flag_diagnostics_all_candidates) > + print_z_candidates (input_location, cand, /*only_viable_p=*/false); > + else > + inform (input_location, > + "use %<-fdiagnostics-all-candidates%> to display " > + "considered candidates"); > + } > + } > return error_mark_node; > } > > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index 5a9284d635c..7e9f68d31b3 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -3311,6 +3311,11 @@ called. If the handler returns, execution continues normally. > @item -fcoroutines > Enable support for the C++ coroutines extension (experimental). > > +@opindex fdiagnostics-all-candidates > +@item -fdiagnostics-all-candidates > +Permit the C++ front end to note all candidates during overload resolution > +failure, including when a deleted function is selected. > + > @opindex fno-elide-constructors > @opindex felide-constructors > @item -fno-elide-constructors > diff --git a/gcc/testsuite/g++.dg/cpp0x/deleted16.C b/gcc/testsuite/g++.dg/cpp0x/deleted16.C > new file mode 100644 > index 00000000000..d4347942c42 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp0x/deleted16.C > @@ -0,0 +1,25 @@ > +// Verify -fdiagnostics-all-candidates makes us note other candidates > +// when a deleted function is selected by overload resolution. > +// { dg-do compile { target c++11 } } > +// { dg-additional-options "-fdiagnostics-all-candidates" } > + > +void f(int) = delete; // { dg-message "declared here" } > +void f(...); // { dg-message "candidate" } > +void f(int, int); // { dg-message "candidate" } > + > +// An example where the perfect candidate optimization causes us > +// to ignore function templates. > +void g(int) = delete; // { dg-message "declared here" } > +template void g(T); // { dg-message "candidate" } > + > +// An example where we have a strictly viable candidate and > +// an incompletely considered bad candidate. > +template void h(T, T) = delete; // { dg-message "declared here|candidate" } > +void h(int*, int) = delete; // { dg-message "candidate" } > + > +int main() { > + f(0); // { dg-error "deleted" } > + g(0); // { dg-error "deleted" } > + h(1, 1); // { dg-error "deleted" } > + // { dg-error "invalid conversion" "" { target *-*-* } .-1 } when noting 2nd cand > +} > diff --git a/gcc/testsuite/g++.dg/cpp0x/deleted16a.C b/gcc/testsuite/g++.dg/cpp0x/deleted16a.C > new file mode 100644 > index 00000000000..e62306fa3d1 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp0x/deleted16a.C > @@ -0,0 +1,12 @@ > +// Verify we suggest -fdiagnostics-all-candidates when diagnosing > +// overload resolution selecting a deleted function. > +// { dg-do compile { target c++11 } } > +#include "deleted16.C" > + > +// { dg-error "deleted" "" { target *-*-* } 21 } > +// { dg-error "deleted" "" { target *-*-* } 22 } > +// { dg-error "deleted" "" { target *-*-* } 23 } > + > +// { dg-message "use '-fdiagnostics-all-candidates'" "" { target *-*-* } 21 } > +// { dg-message "use '-fdiagnostics-all-candidates'" "" { target *-*-* } 22 } > +// { dg-message "use '-fdiagnostics-all-candidates'" "" { target *-*-* } 23 } > diff --git a/gcc/testsuite/g++.dg/overload/error6.C b/gcc/testsuite/g++.dg/overload/error6.C > index 86a12eaa8de..3186a297bfc 100644 > --- a/gcc/testsuite/g++.dg/overload/error6.C > +++ b/gcc/testsuite/g++.dg/overload/error6.C > @@ -1,5 +1,6 @@ > // Verify we note even non-template candidates when diagnosing > // overload resolution failure for a template-id. > +// { dg-additional-options "-fdiagnostics-all-candidates" } > > template void f(T); // { dg-message "candidate" } > void f(int); // { dg-message {candidate: 'void f\(int\)' \(ignored\)} } > diff --git a/gcc/testsuite/g++.dg/overload/error6a.C b/gcc/testsuite/g++.dg/overload/error6a.C > new file mode 100644 > index 00000000000..e86ab5158ab > --- /dev/null > +++ b/gcc/testsuite/g++.dg/overload/error6a.C > @@ -0,0 +1,6 @@ > +// Verify we suggest -fdiagnostics-all-candidates when there are > +// omitted candidates. > +#include "error6.C" > + > +// { dg-error "no match" "" { target *-*-* } 9 } > +// { dg-message "use '-fdiagnostics-all-candidates'" "" { target *-*-* } 9 } > -- > 2.42.0.482.g2e8e77cbac > --8323329-1479004300-1701359163=:41183--