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* [Bug c++/94147] New: mangling of lambdas in initializers is wrong @ 2020-03-11 16:33 nathan at gcc dot gnu.org 2020-03-11 16:33 ` [Bug c++/94147] " nathan at gcc dot gnu.org ` (3 more replies) 0 siblings, 4 replies; 5+ messages in thread From: nathan at gcc dot gnu.org @ 2020-03-11 16:33 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94147 Bug ID: 94147 Summary: mangling of lambdas in initializers is wrong Product: gcc Version: 10.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: nathan at gcc dot gnu.org Target Milestone: --- inline auto var = [] (int) {}; should mangle the lambda as _ZN3varMUlE_clEv likewise for static member variables ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/94147] mangling of lambdas in initializers is wrong 2020-03-11 16:33 [Bug c++/94147] New: mangling of lambdas in initializers is wrong nathan at gcc dot gnu.org @ 2020-03-11 16:33 ` nathan at gcc dot gnu.org 2020-03-18 12:17 ` cvs-commit at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: nathan at gcc dot gnu.org @ 2020-03-11 16:33 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94147 Nathan Sidwell <nathan at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |ASSIGNED Assignee|unassigned at gcc dot gnu.org |nathan at gcc dot gnu.org Ever confirmed|0 |1 Last reconfirmed| |2020-03-11 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/94147] mangling of lambdas in initializers is wrong 2020-03-11 16:33 [Bug c++/94147] New: mangling of lambdas in initializers is wrong nathan at gcc dot gnu.org 2020-03-11 16:33 ` [Bug c++/94147] " nathan at gcc dot gnu.org @ 2020-03-18 12:17 ` cvs-commit at gcc dot gnu.org 2020-03-18 12:17 ` nathan at gcc dot gnu.org 2022-11-28 22:29 ` pinskia at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2020-03-18 12:17 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94147 --- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Nathan Sidwell <nathan@gcc.gnu.org>: https://gcc.gnu.org/g:11cf25c40e3f586d19474108c78a2dfad7925902 commit r10-7243-g11cf25c40e3f586d19474108c78a2dfad7925902 Author: Nathan Sidwell <nathan@acm.org> Date: Wed Mar 18 05:16:28 2020 -0700 PR c++/94147 - mangling of lambdas assigned to globals This patch implements Jason's suggestion of pushing a lambda scope when parsing a global variable initializer. That bit worked fine, but happened to cause g++.dg/opt/dump1.C to not give any used-but-not-defined warnings. The reason was no_linkage_check, which considers any lambda that has an extra-scope to have linkage. Which is technically correct. Except that we think that all types that have linkage have external linkage. Our representation of linkage and visibility is somewhat inaccurate, particularly when it comes to types. We have TREE_PUBLIC, DECL_EXTERNAL, DECL_VISIBILITY, DECL_COMDAT, DECL_NOT_REALLY_EXTERN. It could really do with a through cleanup, but that won't be a simple task. The best I could come up with was seeing if the extra scope was a VAR_DECL, and if that was TREE_PUBLIC and the var was inline (its COMDATness is sadly not set at that point) or a template instantiation, then the lambda had linkage. Otherwise it's as-if it has no-linkage from the POV of compiler internals. This is an ABI change (so we should document it), but it's changing mangling from an unpredictable (in practice) counter, to something the ABI defines. So I'm not concerned about mangling-changed warnings, or preserving the broken mangling under some ABI selection flag. Code that did this worked by accident within a single TU. It'll continue to work by design there, and across TUs. * parser.c (cp_parser_init_declarator): Namespace-scope variables provide a lambda scope. * tree.c (no_linkage_check): Lambdas with a variable for extra scope have a linkage from the variable. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/94147] mangling of lambdas in initializers is wrong 2020-03-11 16:33 [Bug c++/94147] New: mangling of lambdas in initializers is wrong nathan at gcc dot gnu.org 2020-03-11 16:33 ` [Bug c++/94147] " nathan at gcc dot gnu.org 2020-03-18 12:17 ` cvs-commit at gcc dot gnu.org @ 2020-03-18 12:17 ` nathan at gcc dot gnu.org 2022-11-28 22:29 ` pinskia at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: nathan at gcc dot gnu.org @ 2020-03-18 12:17 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94147 Nathan Sidwell <nathan at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED --- Comment #2 from Nathan Sidwell <nathan at gcc dot gnu.org> --- Fixed 11cf25c40e3f586d19474108c78a2dfad7925902 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/94147] mangling of lambdas in initializers is wrong 2020-03-11 16:33 [Bug c++/94147] New: mangling of lambdas in initializers is wrong nathan at gcc dot gnu.org ` (2 preceding siblings ...) 2020-03-18 12:17 ` nathan at gcc dot gnu.org @ 2022-11-28 22:29 ` pinskia at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: pinskia at gcc dot gnu.org @ 2022-11-28 22:29 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94147 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|--- |10.0 ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-11-28 22:29 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-03-11 16:33 [Bug c++/94147] New: mangling of lambdas in initializers is wrong nathan at gcc dot gnu.org 2020-03-11 16:33 ` [Bug c++/94147] " nathan at gcc dot gnu.org 2020-03-18 12:17 ` cvs-commit at gcc dot gnu.org 2020-03-18 12:17 ` nathan at gcc dot gnu.org 2022-11-28 22:29 ` pinskia at gcc dot gnu.org
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