> -----Original Message----- > From: Gcc-patches <gcc-patches- > bounces+kyrylo.tkachov=arm....@gcc.gnu.org> On Behalf Of Arthur Cohen > Sent: Wednesday, December 14, 2022 10:05 AM > To: Jakub Jelinek <ja...@redhat.com>; gcc-r...@gcc.gnu.org; gcc- > patc...@gcc.gnu.org > Subject: Re: [PATCH] rust: Fix up aarch64-linux bootstrap [PR106072] > > Hi Jakub, > > On 12/14/22 10:14, Jakub Jelinek via Gcc-rust wrote: > > Hi! > > > > Bootstrap fails on aarch64-linux and some other arches with: > > .../gcc/rust/parse/rust-parse-impl.h: In member function > ‘Rust::AST::ClosureParam > Rust::Parser<ManagedTokenSource>::parse_closure_param() [with > ManagedTokenSource = Rust::Lexer]’: > > .../gcc/rust/parse/rust-parse-impl.h:8916:49: error: ‘this’ pointer is null > > [- > Werror=nonnull] > > The problem is that while say on x86_64-linux the side-effects in the > > arguments are evaluated from last argument to first, on aarch64-linux > > it is the other way around, from first to last. The C++ I believe even > > in C++17 makes the evaluation of those side-effects unordered > > (indeterminately sequenced with no interleaving), so that is fine. > > But, when the call in return statement is evaluated from first to > > last, std::move (pattern) happens before pattern->get_locus () and > > the former will make pattern (std::unique_ptr) a wrapper object around > > nullptr, so dereferencing it later to call get_locus () on it is invalid. > > > > The following patch fixes that, ok for trunk?
FWIW, with this patch my aarch64 bootstrap progressed past the previous point of failure (it's currently in stage 3). Thanks, Kyrill > > > > 2022-12-14 Jakub Jelinek <ja...@redhat.com> > > > > PR rust/106072 > > * parse/rust-parse-impl.h (parse_closure_param): Store > > pattern->get_locus () in a temporary before std::move (pattern) is > > invoked. > > > > --- gcc/rust/parse/rust-parse-impl.h.jj 2022-12-13 > 16:50:12.708093521 +0100 > > +++ gcc/rust/parse/rust-parse-impl.h 2022-12-14 09:50:31.731111932 > +0100 > > @@ -8912,8 +8912,9 @@ Parser<ManagedTokenSource>::parse_closur > > } > > } > > > > - return AST::ClosureParam (std::move (pattern), pattern->get_locus (), > > - std::move (type), std::move (outer_attrs)); > > + Location loc = pattern->get_locus (); > > + return AST::ClosureParam (std::move (pattern), loc, std::move (type), > > + std::move (outer_attrs)); > > } > > > > // Parses a grouped or tuple expression (disambiguates). > > > > Jakub > > > > Thanks :) this looks good to me. We already have that issue fixed in our > upstream dev branch, by this PR: > > https://github.com/Rust-GCC/gccrs/pull/1619 > > but we have yet to update GCC's master with our upstream dev branch, so > in the meantime feel free to apply your patch. When I'll get to updating > master, I'm expecting these kinds of tiny conflicts and we'll deal with > them. > > Thanks a lot for working on this and sorry that my tardiness in updating > has caused a duplication of efforts. > > All the best, > > -- > Arthur Cohen <arthur.co...@embecosm.com> > > Toolchain Engineer > > Embecosm GmbH > > Geschäftsführer: Jeremy Bennett > Niederlassung: Nürnberg > Handelsregister: HR-B 36368 > www.embecosm.de > > Fürther Str. 27 > 90429 Nürnberg > > > Tel.: 091 - 128 707 040 > Fax: 091 - 128 707 077
