Subpart9 for async drop (major3) - elaborate_drops changes

[azhogin]

This is subpart 9 PR of #123948, just for review purposes.

Changes in drop elaboration to support async drops.
Drop elaboration is used to generate sync drop glue with drops of all internals included.
Async drop poll function is generated now using a similar way - first splitting dropee type using drop elaboration, and then StateTransform'ing it into coroutine poll function (StateTransform changes and shim generation in latter commits).

Review only last commit, based on previous PR #129744.

[bors]

☔ The latest upstream changes (presumably #130165) made this pull request unmergeable. Please resolve the merge conflicts.

[davidtwco]

r? @nikomatsakis is going to look into this

[rust-log-analyzer]

The job x86_64-gnu-llvm-19 failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

#20 exporting to docker image format
#20 sending tarball 19.9s done
#20 DONE 25.4s
##[endgroup]
Setting extra environment values for docker:  --env ENABLE_GCC_CODEGEN=1 --env GCC_EXEC_PREFIX=/usr/lib/gcc/
[CI_JOB_NAME=x86_64-gnu-llvm-19]
[CI_JOB_NAME=x86_64-gnu-llvm-19]
debug: `DISABLE_CI_RUSTC_IF_INCOMPATIBLE` configured.
---
sccache: Listening on address 127.0.0.1:4226
##[group]Configure the build
configure: processing command line
configure: 
configure: build.configure-args := ['--build=x86_64-unknown-linux-gnu', '--llvm-root=/usr/lib/llvm-19', '--enable-llvm-link-shared', '--set', 'rust.randomize-layout=true', '--set', 'rust.thin-lto-import-instr-limit=10', '--set', 'build.print-step-timings', '--enable-verbose-tests', '--set', 'build.metrics', '--enable-verbose-configure', '--enable-sccache', '--disable-manage-submodules', '--enable-locked-deps', '--enable-cargo-native-static', '--set', 'rust.codegen-units-std=1', '--set', 'dist.compression-profile=balanced', '--dist-compression-formats=xz', '--set', 'rust.lld=false', '--disable-dist-src', '--release-channel=nightly', '--enable-debug-assertions', '--enable-overflow-checks', '--enable-llvm-assertions', '--set', 'rust.verify-llvm-ir', '--set', 'rust.codegen-backends=llvm,cranelift,gcc', '--set', 'llvm.static-libstdcpp', '--enable-new-symbol-mangling']
configure: build.build          := x86_64-unknown-linux-gnu
configure: target.x86_64-unknown-linux-gnu.llvm-config := /usr/lib/llvm-19/bin/llvm-config
configure: llvm.link-shared     := True
configure: rust.randomize-layout := True
configure: rust.thin-lto-import-instr-limit := 10
---
  Number of decisions:   4447
  longest path:          1159 (code:    152)
  longest backtrack:       66 (code:    428)
Shared 86733 out of 152951 states by creating 14756 new states, saving 71977
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/expmed.cc: In function ‘rtx_def* extract_bit_field_1(rtx, poly_uint64, poly_uint64, int, rtx, machine_mode, machine_mode, bool, bool, rtx_def**)’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/expmed.cc:1864:45: warning: ‘*(unsigned int*)((char*)&imode + offsetof(scalar_int_mode, scalar_int_mode::m_mode))’ may be used uninitialized [-Wmaybe-uninitialized]
 1864 |       rtx sub = extract_bit_field_as_subreg (mode1, op0, imode,
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
 1865 |                                              bitsize, bitnum);
      |                                              ~~~~~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/expmed.cc:1824:19: note: ‘*(unsigned int*)((char*)&imode + offsetof(scalar_int_mode, scalar_int_mode::m_mode))’ was declared here
 1824 |   scalar_int_mode imode;
      |                   ^~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/gimple-range-gori.cc: In member function ‘void range_def_chain::dump(FILE*, basic_block, const char*)’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/gimple-range-gori.cc:319:19: warning: format not a string literal and no format arguments [-Wformat-security]
  319 |           fprintf (f, prefix);
      |           ~~~~~~~~^~~~~~~~~~~
---
                 from /checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/analyzer/region-model.h:33,
                 from /checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/analyzer/access-diagram.cc:39:
In constructor ‘ana::byte_range::byte_range(ana::byte_offset_t, ana::byte_size_t)’,
    inlined from ‘virtual text_art::table ana::string_literal_spatial_item::make_table(const ana::bit_to_table_map&, text_art::style_manager&) const’ at /checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/analyzer/access-diagram.cc:1812:18:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/analyzer/store.h:312:5: warning: ‘size_in_bytes.generic_wide_int<fixed_wide_int_storage<128> >::fixed_wide_int_storage<128>.fixed_wide_int_storage<128>::val[1]’ may be used uninitialized [-Wmaybe-uninitialized]
  312 |     m_size_in_bytes (size_in_bytes)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/analyzer/access-diagram.cc: In member function ‘virtual text_art::table ana::string_literal_spatial_item::make_table(const ana::bit_to_table_map&, text_art::style_manager&) const’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/analyzer/access-diagram.cc:1808:28: note: ‘size_in_bytes.generic_wide_int<fixed_wide_int_storage<128> >::fixed_wide_int_storage<128>.fixed_wide_int_storage<128>::val[1]’ was declared here
 1808 |                byte_size_t size_in_bytes
      |                            ^~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/diagnostic.cc: In function ‘void fancy_abort(const char*, int, const char*)’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/diagnostic.cc:1677:15: warning: format not a string literal and no format arguments [-Wformat-security]
 1677 |       fnotice (stderr, diagnostic_kind_text[DK_ICE]);
---
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/gcc.cc:7930:9: warning: ignoring return value of ‘ssize_t write(int, const void*, size_t)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 7930 |   write (fd, "\n\n", 2);
      |   ~~~~~~^~~~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/gcc.cc: In member function ‘void driver::final_actions() const’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/gcc.cc:9307:13: warning: ignoring return value of ‘int truncate(const char*, __off_t)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 9307 |     truncate(totruncate_file, 0);
      |     ~~~~~~~~^~~~~~~~~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/gengtype-lex.l: In function ‘int yylex(const char**)’:
gengtype-lex.cc:357:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
  357 | #define YY_DO_BEFORE_ACTION \
      |  ~~~~~~~~~~~~~^~~~~~~
---
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/lto/lto-common.cc: In function ‘void lto_resolution_read(splay_tree, FILE*, lto_file*)’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/lto/lto-common.cc:2091:10: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 2091 |   fscanf (resolution, " ");   /* Read white space.  */
      |   ~~~~~~~^~~~~~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/lto/lto-common.cc:2093:9: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 2093 |   fread (obj_name, sizeof (char), name_len, resolution);
      |   ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/lto/lto-common.cc:2113:10: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 2113 |   fscanf (resolution, "%u", &num_symbols);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/gcc/jit/jit-recording.cc:32:
---
Applying io_quotes_use            to linux/blkzoned.h
Applying io_quotes_use            to linux/ipmi.h
Applying io_quotes_use            to linux/psp-dbc.h
Applying io_quotes_use            to linux/bt-bmc.h
Applying io_quotes_use            to linux/tps6594_pfsm.h
Applying io_quotes_use            to linux/cxl_mem.h
Applying io_quotes_use            to linux/wmi.h
Applying io_quotes_use            to linux/auto_fs.h
Applying io_quotes_use            to linux/mmtimer.h
Applying io_quotes_use            to linux/f2fs.h
Applying io_quotes_use            to linux/vhost.h
---
Applying io_quotes_use            to sound/asound.h
Applying io_quotes_use            to sound/compress_offload.h
Applying hpux8_bogus_inlines      to math.h
Applying pthread_incomplete_struct_argument to pthread.h
Fixed:  pthread.h
Applying io_quotes_use            to misc/mrvl_cn10k_dpi.h
Applying io_quotes_use            to misc/ocxl.h
Applying io_quotes_use            to misc/cxl.h
Applying io_quotes_use            to misc/xilinx_sdfec.h
Applying io_quotes_def            to unicode/platform.h
Applying sun_malloc               to malloc.h
Applying io_quotes_use            to scsi/cxlflash_ioctl.h
---
Applying machine_name             to x86_64-linux-gnu/bits/unistd_ext.h
Applying io_quotes_use            to x86_64-linux-gnu/asm/mtrr.h
Applying io_quotes_use            to x86_64-linux-gnu/asm/amd_hsmp.h
Applying machine_name             to openssl/e_os2.h
Applying io_quotes_use            to drm/xe_drm.h
Applying io_quotes_use            to drm/radeon_drm.h
Applying io_quotes_use            to drm/panfrost_drm.h
Applying io_quotes_use            to drm/etnaviv_drm.h
Applying io_quotes_use            to drm/lima_drm.h
Applying io_quotes_use            to drm/qaic_accel.h
Applying io_quotes_use            to drm/vc4_drm.h
Applying io_quotes_use            to drm/i915_drm.h
Applying io_quotes_use            to drm/omap_drm.h
Applying io_quotes_use            to drm/pvr_drm.h
Applying io_quotes_use            to drm/amdgpu_drm.h
Applying io_quotes_use            to drm/vgem_drm.h
Applying io_quotes_use            to drm/msm_drm.h
Applying io_quotes_use            to drm/v3d_drm.h
Applying io_quotes_use            to drm/exynos_drm.h
Applying io_quotes_use            to drm/nouveau_drm.h
Applying io_quotes_use            to drm/drm.h
Applying io_quotes_use            to drm/habanalabs_accel.h
Applying io_quotes_use            to drm/tegra_drm.h
Applying io_quotes_use            to rdma/rdma_user_ioctl.h
cc1: note: self-tests are not enabled in this build
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/c++tools/server.cc: In function ‘void server(bool, int, module_resolver*)’:
/checkout/obj/build/x86_64-unknown-linux-gnu/gcc/src/c++tools/server.cc:620:10: warning: ignoring return value of ‘int pipe(int*)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
---
---- [ui] tests/ui/async-await/async-drop/ex-ice-132103.rs stdout ----

error: Error: expected failure status (Some(1)) but received status Some(101).
status: exit status: 101
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/async-await/async-drop/ex-ice-132103.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2" "--target=x86_64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/async-await/async-drop/ex-ice-132103" "-A" "unused" "-A" "internal_features" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "-Zvalidate-mir" "--edition=2018" "-Zinline-mir=yes"
stdout: none
--- stderr -------------------------------
error[E0658]: use of unstable library feature `async_drop`
##[error]  --> /checkout/tests/ui/async-await/async-drop/ex-ice-132103.rs:4:20
   |
LL | use core::future::{async_drop_in_place, Future};
   |                    ^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
   = help: add `#![feature(async_drop)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `async_drop`
##[error]  --> /checkout/tests/ui/async-await/async-drop/ex-ice-132103.rs:12:19
   |
LL |     pin!(unsafe { async_drop_in_place(x.as_mut_ptr()) });
   |                   ^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
   = help: add `#![feature(async_drop)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

##[error]error: internal compiler error: compiler/rustc_mir_transform/src/shim.rs:137:13: AsyncDropGlueCtorShim in re-working (AsyncDropGlueCtorShim(DefId(2:15012 ~ core[b50a]::future::async_drop::async_drop_in_place), Coroutine(DefId(0:15 ~ ex_ice_132103[2735]::test_async_drop::{closure#0}), [i32, (), std::future::ResumeTy, (), (), CoroutineWitness(DefId(0:15 ~ ex_ice_132103[2735]::test_async_drop::{closure#0}), [i32]), (i32,)])))


thread 'rustc' panicked at compiler/rustc_mir_transform/src/shim.rs:137:13:
Box<dyn Any>
stack backtrace:
   0: std::panicking::begin_panic::<rustc_errors::ExplicitBug>
   1: <rustc_errors::diagnostic::BugAbort as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
   2: rustc_middle::util::bug::opt_span_bug_fmt::<rustc_span::span_encoding::Span>::{closure#0}
   3: rustc_middle::ty::context::tls::with_opt::<rustc_middle::util::bug::opt_span_bug_fmt<rustc_span::span_encoding::Span>::{closure#0}, !>::{closure#0}
   4: rustc_middle::ty::context::tls::with_context_opt::<rustc_middle::ty::context::tls::with_opt<rustc_middle::util::bug::opt_span_bug_fmt<rustc_span::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
   5: rustc_middle::util::bug::bug_fmt
   6: rustc_mir_transform::shim::make_shim
      [... omitted 3 frames ...]
   7: <rustc_middle::ty::context::TyCtxt>::instance_mir
   8: rustc_mir_transform::inline::cycle::mir_inliner_callees
      [... omitted 3 frames ...]
   9: rustc_mir_transform::inline::cycle::mir_callgraph_reachable::process
  10: rustc_mir_transform::inline::cycle::mir_callgraph_reachable::process
  11: rustc_mir_transform::inline::cycle::mir_callgraph_reachable::process
  12: rustc_mir_transform::inline::cycle::mir_callgraph_reachable
      [... omitted 3 frames ...]
  13: rustc_mir_transform::inline::process_blocks::<rustc_mir_transform::inline::NormalInliner>
  14: <rustc_mir_transform::inline::Inline as rustc_mir_transform::pass_manager::MirPass>::run_pass
  15: rustc_mir_transform::pass_manager::run_passes_inner
  16: rustc_mir_transform::optimized_mir
      [... omitted 3 frames ...]
  17: <rustc_middle::ty::context::TyCtxt>::instance_mir
  18: <rustc_data_structures::sync::parallel::ParallelGuard>::run::<(), rustc_data_structures::sync::parallel::par_for_each_in<&rustc_span::def_id::LocalDefId, &[rustc_span::def_id::LocalDefId], <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners<rustc_interface::passes::run_required_analyses::{closure#7}::{closure#0}>::{closure#0}>::{closure#0}::{closure#1}::{closure#0}>
  19: <rustc_session::session::Session>::time::<(), rustc_interface::passes::run_required_analyses::{closure#7}>
  20: rustc_interface::passes::analysis
      [... omitted 3 frames ...]
  21: <std::thread::local::LocalKey<core::cell::Cell<*const ()>>>::with::<rustc_middle::ty::context::tls::enter_context<<rustc_middle::ty::context::GlobalCtxt>::enter<rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}, core::option::Option<rustc_interface::queries::Linker>>::{closure#1}, core::option::Option<rustc_interface::queries::Linker>>::{closure#0}, core::option::Option<rustc_interface::queries::Linker>>
  22: <rustc_middle::ty::context::TyCtxt>::create_global_ctxt::<core::option::Option<rustc_interface::queries::Linker>, rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}>
  23: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
  24: <alloc::boxed::Box<dyn for<'a> core::ops::function::FnOnce<(&'a rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, &'a std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt<'a>>, &'a rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena<'a>>, &'a rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena<'a>>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}), Output = core::option::Option<rustc_interface::queries::Linker>>> as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once
  25: rustc_interface::passes::create_and_enter_global_ctxt::<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>
  26: <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: please make sure that you have updated to the latest nightly

note: rustc 1.88.0-nightly (1a0a15247 2025-04-06) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z threads=1 -Z simulate-remapped-rust-src-base=/rustc/FAKE_PREFIX -Z translate-remapped-path-to-local-path=no -Z ignore-directory-in-diagnostics-source-blocks=/cargo -Z ignore-directory-in-diagnostics-source-blocks=/checkout/vendor -C codegen-units=1 -Z ui-testing -Z deduplicate-diagnostics=no -Z write-long-types-to-disk=no -C strip=debuginfo -C prefer-dynamic -C rpath -C debuginfo=0 -Z validate-mir -Z inline-mir=yes

query stack during panic:
#0 [mir_shims] generating MIR shim for `core::future::async_drop::async_drop_in_place`, instance=AsyncDropGlueCtorShim(DefId(2:15012 ~ core[b50a]::future::async_drop::async_drop_in_place), Coroutine(DefId(0:15 ~ ex_ice_132103[2735]::test_async_drop::{closure#0}), [i32, (), core::future::ResumeTy, (), (), CoroutineWitness(DefId(0:15 ~ ex_ice_132103[2735]::test_async_drop::{closure#0}), [i32]), (i32,)]))
#1 [mir_inliner_callees] computing all local function calls in `core::future::async_drop::async_drop_in_place`
#2 [mir_callgraph_reachable] computing if `main::{closure#0}` (transitively) calls `main`
#3 [optimized_mir] optimizing MIR for `main`
#4 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors

---
2   --> $DIR/feature-gate-async-drop.rs:3:5
3    |
4 LL | use std::future::AsyncDrop;

8    = help: add `#![feature(async_drop)]` to the crate attributes to enable
9    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
10 
- error[E0658]: use of unstable library feature 'async_drop'
+ error[E0658]: use of unstable library feature `async_drop`
12   --> $DIR/feature-gate-async-drop.rs:13:5
13    |
14 LL |     async fn drop(self: Pin<&mut Self>) {}

18    = help: add `#![feature(async_drop)]` to the crate attributes to enable
19    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
20 
- error[E0658]: use of unstable library feature 'async_drop'
+ error[E0658]: use of unstable library feature `async_drop`
22   --> $DIR/feature-gate-async-drop.rs:12:6
23    |
---
To only update this specific test, also pass `--test-args feature-gates/feature-gate-async-drop.rs`

error: 1 errors occurred comparing output.
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/feature-gates/feature-gate-async-drop.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2" "--target=x86_64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/feature-gates/feature-gate-async-drop" "-A" "unused" "-A" "internal_features" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--edition=2021"
stdout: none
--- stderr -------------------------------
error[E0658]: use of unstable library feature `async_drop`
##[error]  --> /checkout/tests/ui/feature-gates/feature-gate-async-drop.rs:3:5
   |
LL | use std::future::AsyncDrop; //~ ERROR  use of unstable library feature 'async_drop'
   |     ^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
   = help: add `#![feature(async_drop)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `async_drop`
##[error]  --> /checkout/tests/ui/feature-gates/feature-gate-async-drop.rs:13:5
   |
LL |     async fn drop(self: Pin<&mut Self>) {} //~ ERROR  use of unstable library feature 'async_drop'
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
   = help: add `#![feature(async_drop)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `async_drop`
##[error]  --> /checkout/tests/ui/feature-gates/feature-gate-async-drop.rs:12:6
   |
LL | impl AsyncDrop for Foo { //~ ERROR  use of unstable library feature 'async_drop'
   |      ^^^^^^^^^
   |
   = note: see issue #126482 <https://github.com/rust-lang/rust/issues/126482> for more information
   = help: add `#![feature(async_drop)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0658`.
------------------------------------------

[bors]

☔ The latest upstream changes (presumably #139578) made this pull request unmergeable. Please resolve the merge conflicts.

[petrochenkov]

#123948 was merged.