rustc 1.56.0 : double free on OpenBSD sparc64

[semarie]

I am currently preparing packaging of rustc 1.56.0 for OpenBSD.

On sparc64, while compiling alloc, the build aborts due to double free (OpenBSD libc detects it and abort).

If I correctly understand the place, the double free occurs with stage1, which is 1.56.0 code built using 1.55.0.

It is a regression from previous stable, as building 1.55.0 was fine.

Any pointer would be appreciate.

The build log for alloc is the following:

   Compiling alloc v0.0.0 (/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/library/alloc)
     Running `/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/bootstrap/debug/rustc --crate-name alloc --edition=2018 library/alloc/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts --crate-type lib --emit=dep-info,metadata,link -C opt-level=3 -C embed-bitcode=no -C debuginfo=0 --cfg 'feature="compiler-builtins-c"' -C metadata=a2d2e271a66d2a4c -C extra-filename=-a2d2e271a66d2a4c --out-dir /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps --target sparc64-unknown-openbsd -L dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps -L dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/release/deps --extern compiler_builtins=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcompiler_builtins-7b676bd92d7e6db5.rmeta --extern core=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcore-b2a58fb9eb0abee9.rmeta -Zmacro-backtrace -Zsave-analysis -Cprefer-dynamic -Cembed-bitcode=yes '-Zcrate-attr=doc(html_root_url="https://doc.rust-lang.org/1.56.0/")' -Z binary-dep-depinfo -L native=/usr/lib`
[RUSTC-SHIM] rustc alloc env[0]: "CARGO"="/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-bootstrap-sparc64-1.55.0-20210907/bin/cargo.bin"
[RUSTC-SHIM] rustc alloc env[1]: "CARGO_CRATE_NAME"="alloc"
[RUSTC-SHIM] rustc alloc env[2]: "CARGO_HOME"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/cargo-home"
[RUSTC-SHIM] rustc alloc env[3]: "CARGO_INCREMENTAL"="0"
[RUSTC-SHIM] rustc alloc env[4]: "CARGO_MAKEFLAGS"="-j --jobserver-fds=5,6 --jobserver-auth=5,6"
[RUSTC-SHIM] rustc alloc env[5]: "CARGO_MANIFEST_DIR"="/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/library/alloc"
[RUSTC-SHIM] rustc alloc env[6]: "CARGO_PKG_AUTHORS"=""
[RUSTC-SHIM] rustc alloc env[7]: "CARGO_PKG_DESCRIPTION"="The Rust core allocation and collections library"
[RUSTC-SHIM] rustc alloc env[8]: "CARGO_PKG_HOMEPAGE"=""
[RUSTC-SHIM] rustc alloc env[9]: "CARGO_PKG_LICENSE"="MIT OR Apache-2.0"
[RUSTC-SHIM] rustc alloc env[10]: "CARGO_PKG_LICENSE_FILE"=""
[RUSTC-SHIM] rustc alloc env[11]: "CARGO_PKG_NAME"="alloc"
[RUSTC-SHIM] rustc alloc env[12]: "CARGO_PKG_REPOSITORY"="https://github.com/rust-lang/rust.git"
[RUSTC-SHIM] rustc alloc env[13]: "CARGO_PKG_VERSION"="0.0.0"
[RUSTC-SHIM] rustc alloc env[14]: "CARGO_PKG_VERSION_MAJOR"="0"
[RUSTC-SHIM] rustc alloc env[15]: "CARGO_PKG_VERSION_MINOR"="0"
[RUSTC-SHIM] rustc alloc env[16]: "CARGO_PKG_VERSION_PATCH"="0"
[RUSTC-SHIM] rustc alloc env[17]: "CARGO_PKG_VERSION_PRE"=""
[RUSTC-SHIM] rustc alloc env[18]: "CARGO_PROFILE_RELEASE_DEBUG"="0"
[RUSTC-SHIM] rustc alloc env[19]: "CARGO_PROFILE_RELEASE_DEBUG_ASSERTIONS"="false"
[RUSTC-SHIM] rustc alloc env[20]: "CARGO_PROFILE_RELEASE_OVERFLOW_CHECKS"="false"
[RUSTC-SHIM] rustc alloc env[21]: "CARGO_TARGET_DIR"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std"
[RUSTC-SHIM] rustc alloc env[22]: "RUSTBUILD_NATIVE_DIR"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/native"
[RUSTC-SHIM] rustc alloc env[23]: "RUSTC"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/bootstrap/debug/rustc"
[RUSTC-SHIM] rustc alloc env[24]: "RUSTC_BOOTSTRAP"="1"
[RUSTC-SHIM] rustc alloc env[25]: "RUSTC_BREAK_ON_ICE"="1"
[RUSTC-SHIM] rustc alloc env[26]: "RUSTC_ERROR_METADATA_DST"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/tmp/extended-error-metadata"
[RUSTC-SHIM] rustc alloc env[27]: "RUSTC_FORCE_UNSTABLE"="1"
[RUSTC-SHIM] rustc alloc env[28]: "RUSTC_INSTALL_BINDIR"="bin"
[RUSTC-SHIM] rustc alloc env[29]: "RUSTC_LIBDIR"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib"
[RUSTC-SHIM] rustc alloc env[30]: "RUSTC_LINT_FLAGS"="-Wrust_2018_idioms -Wunused_lifetimes -Wsemicolon_in_expressions_from_macros -Dwarnings"
[RUSTC-SHIM] rustc alloc env[31]: "RUSTC_REAL"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/bin/rustc"
[RUSTC-SHIM] rustc alloc env[32]: "RUSTC_SNAPSHOT"="/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-bootstrap-sparc64-1.55.0-20210907/bin/rustc"
[RUSTC-SHIM] rustc alloc env[33]: "RUSTC_SNAPSHOT_LIBDIR"="/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-bootstrap-sparc64-1.55.0-20210907/lib"
[RUSTC-SHIM] rustc alloc env[34]: "RUSTC_STAGE"="1"
[RUSTC-SHIM] rustc alloc env[35]: "RUSTC_SYSROOT"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1"
[RUSTC-SHIM] rustc alloc env[36]: "RUSTC_VERBOSE"="2"
[RUSTC-SHIM] rustc alloc env[37]: "RUSTDOC"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/bootstrap/debug/rustdoc"
[RUSTC-SHIM] rustc alloc env[38]: "RUSTDOCFLAGS"="-Dwarnings -Wrustdoc::invalid_codeblock_attributes --crate-version 1.56.0 -Zcrate-attr=doc(html_root_url=\"https://doc.rust-lang.org/1.56.0/\")"
[RUSTC-SHIM] rustc alloc env[39]: "RUSTDOC_REAL"="/path/to/nowhere/rustdoc/not/required"
[RUSTC-SHIM] rustc alloc env[40]: "RUSTFLAGS"="-Zmacro-backtrace -Zsave-analysis -Cprefer-dynamic -Cembed-bitcode=yes -Zcrate-attr=doc(html_root_url=\"https://doc.rust-lang.org/1.56.0/\")"
[RUSTC-SHIM] rustc alloc env[41]: "RUST_COMPILER_RT_ROOT"="/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/src/llvm-project/compiler-rt"
[RUSTC-SHIM] rustc alloc env[42]: "RUST_SAVE_ANALYSIS_CONFIG"="{\"output_file\": null,\"full_docs\": false,\"pub_only\": true,\"reachable_only\": false,\"distro_crate\": true,\"signatures\": false,\"borrow_data\": false}"
[RUSTC-SHIM] rustc alloc env[43]: "RUST_TEST_THREADS"="1"
[RUSTC-SHIM] rustc alloc working directory: /home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src
[RUSTC-SHIM] rustc alloc command: "LD_LIBRARY_PATH"="/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib:/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/release/deps:/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-bootstrap-sparc64-1.55.0-20210907/lib:/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-bootstrap-sparc64-1.55.0-20210907/bin/../lib" "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/bin/rustc" "--crate-name" "alloc" "--edition=2018" "library/alloc/src/lib.rs" "--error-format=json" "--json=diagnostic-rendered-ansi,artifacts" "--crate-type" "lib" "--emit=dep-info,metadata,link" "-C" "opt-level=3" "-C" "embed-bitcode=no" "-C" "debuginfo=0" "--cfg" "feature=\"compiler-builtins-c\"" "-C" "metadata=a2d2e271a66d2a4c" "-C" "extra-filename=-a2d2e271a66d2a4c" "--out-dir" "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps" "--target" "sparc64-unknown-openbsd" "-L" "dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps" "-L" "dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/release/deps" "--extern" "compiler_builtins=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcompiler_builtins-7b676bd92d7e6db5.rmeta" "--extern" "core=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcore-b2a58fb9eb0abee9.rmeta" "-Zmacro-backtrace" "-Zsave-analysis" "-Cprefer-dynamic" "-Cembed-bitcode=yes" "-Zcrate-attr=doc(html_root_url=\"https://doc.rust-lang.org/1.56.0/\")" "-Z" "binary-dep-depinfo" "-L" "native=/usr/lib" "-Wrust_2018_idioms" "-Wunused_lifetimes" "-Wsemicolon_in_expressions_from_macros" "-Dwarnings" "--sysroot" "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1" "-Z" "force-unstable-if-unmarked"
[RUSTC-SHIM] rustc alloc sysroot: "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1"
[RUSTC-SHIM] rustc alloc libdir: "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib"
rustc(46711) in free(): double free 0xf71c807970

Did not run successfully: signal: 6 (core dumped)
"/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/bin/rustc" "--crate-name" "alloc" "--edition=2018" "library/alloc/src/lib.rs" "--error-format=json" "--json=diagnostic-rendered-ansi,artifacts" "--crate-type" "lib" "--emit=dep-info,metadata,link" "-C" "opt-level=3" "-C" "embed-bitcode=no" "-C" "debuginfo=0" "--cfg" "feature=\"compiler-builtins-c\"" "-C" "metadata=a2d2e271a66d2a4c" "-C" "extra-filename=-a2d2e271a66d2a4c" "--out-dir" "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps" "--target" "sparc64-unknown-openbsd" "-L" "dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps" "-L" "dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/release/deps" "--extern" "compiler_builtins=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcompiler_builtins-7b676bd92d7e6db5.rmeta" "--extern" "core=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcore-b2a58fb9eb0abee9.rmeta" "-Zmacro-backtrace" "-Zsave-analysis" "-Cprefer-dynamic" "-Cembed-bitcode=yes" "-Zcrate-attr=doc(html_root_url=\"https://doc.rust-lang.org/1.56.0/\")" "-Z" "binary-dep-depinfo" "-L" "native=/usr/lib" "-Wrust_2018_idioms" "-Wunused_lifetimes" "-Wsemicolon_in_expressions_from_macros" "-Dwarnings" "--sysroot" "/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1" "-Z" "force-unstable-if-unmarked"
rustc exited with signal: 6 (core dumped)
-------------
error: could not compile `alloc`

Caused by:
  process didn't exit successfully: `/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/bootstrap/debug/rustc --crate-name alloc --edition=2018 library/alloc/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts --crate-type lib --emit=dep-info,metadata,link -C opt-level=3 -C embed-bitcode=no -C debuginfo=0 --cfg 'feature="compiler-builtins-c"' -C metadata=a2d2e271a66d2a4c -C extra-filename=-a2d2e271a66d2a4c --out-dir /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps --target sparc64-unknown-openbsd -L dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps -L dependency=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/release/deps --extern compiler_builtins=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcompiler_builtins-7b676bd92d7e6db5.rmeta --extern core=/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1-std/sparc64-unknown-openbsd/release/deps/libcore-b2a58fb9eb0abee9.rmeta -Zmacro-backtrace -Zsave-analysis -Cprefer-dynamic -Cembed-bitcode=yes '-Zcrate-attr=doc(html_root_url="https://doc.rust-lang.org/1.56.0/")' -Z binary-dep-depinfo -L native=/usr/lib` (exit status: 254)
command did not execute successfully: "/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-bootstrap-sparc64-1.55.0-20210907/bin/cargo" "build" "--target" "sparc64-unknown-openbsd" "-Zbinary-dep-depinfo" "-j" "1" "-v" "--release" "--frozen" "--features" "panic-unwind backtrace compiler-builtins-c" "--manifest-path" "/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/library/test/Cargo.toml" "--message-format" "json-render-diagnostics"
expected success, got: exit status: 101
Traceback (most recent call last):
  File "/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/x.py", line 27, in <module>
    bootstrap.main()
  File "/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/src/bootstrap/bootstrap.py", line 1217, in main
    bootstrap(help_triggered)
  File "/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/src/bootstrap/bootstrap.py", line 1203, in bootstrap
    run(args, env=env, verbose=build.verbose, is_bootstrap=True)
  File "/home/semarie/repos/ports/pobj/rust-1.56.0/rustc-1.56.0-src/src/bootstrap/bootstrap.py", line 153, in run
    raise RuntimeError(err)
RuntimeError: failed to run: /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/bootstrap/debug/bootstrap dist --jobs=1 library/std src/librustc cargo clippy rustfmt
*** Error 1 in . (Makefile:243 'do-build')
*** Error 2 in . (/home/semarie/repos/ports/infrastructure/mk/bsd.port.mk:2952 '/home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/.build_done')
*** Error 2 in /home/semarie/ports/mystuff/lang/rust (/home/semarie/repos/ports/infrastructure/mk/bsd.port.mk:2602 'all': @lock=rust-1.56.0;...)

gdb backtrace:

(gdb) bt
#0  *_libc_abort () at /usr/src/lib/libc/stdlib/abort.c:57
#1  0x000000f72077127c in wrterror (d=0xf6d0ec95c0, msg=0xf720929518 "double free %p") at /usr/src/lib/libc/stdlib/malloc.c:307
#2  0x000000f7207748a4 in ofree (argpool=0xf7668ea6b0, p=0xf71c807970, clear=0, check=<optimized out>, argsz=0) at /usr/src/lib/libc/stdlib/malloc.c:1425
#3  0x000000f720775318 in free (ptr=0xf71c807970) at /usr/src/lib/libc/stdlib/malloc.c:1470
#4  0x000000f6e380530c in __rdl_dealloc () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/libstd-2f7fa7da8a3eb261.so
#5  0x000000f6e384d7e0 in __rust_dealloc () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/libstd-2f7fa7da8a3eb261.so
#6  0x000000f6e7c27168 in _$LT$rustc_mir..transform..abort_unwinding_calls..AbortUnwindingCalls$u20$as$u20$rustc_mir..transform..MirPass$GT$::run_pass::h053c381204964e57 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#7  0x000000f6e7b73934 in rustc_mir::transform::run_passes::hc5a79e705cf4b7ff () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#8  0x000000f6e7b7b008 in rustc_mir::transform::run_post_borrowck_cleanup_passes::h1f2ad3a24b17ef86 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#9  0x000000f6e7b7a1c8 in rustc_mir::transform::mir_drops_elaborated_and_const_checked::h2e7a148809863d0a ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#10 0x000000f6e85098a8 in rustc_query_system::query::plumbing::get_query_impl::h31223dfb84119524 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#11 0x000000f6e8b94204 in _$LT$rustc_query_impl..Queries$u20$as$u20$rustc_middle..ty..query..QueryEngine$GT$::mir_drops_elaborated_and_const_checked::hf319f0f0f0dd3967 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#12 0x000000f6e7b7bb34 in rustc_mir::transform::optimized_mir::h0a18ce025c9996e9 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#13 0x000000f6e85142f4 in rustc_query_system::query::plumbing::get_query_impl::h39907df79a9efdb6 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#14 0x000000f6e8b946bc in _$LT$rustc_query_impl..Queries$u20$as$u20$rustc_middle..ty..query..QueryEngine$GT$::optimized_mir::h5943a6dd3a5a7341 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#15 0x000000f6e9de6820 in rustc_middle::ty::_$LT$impl$u20$rustc_middle..ty..context..TyCtxt$GT$::instance_mir::h36a0164fbb838479 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#16 0x000000f6e7cc2f94 in rustc_mir::monomorphize::collector::collect_neighbours::hd7e072505b151b21 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#17 0x000000f6e7cba1c8 in rustc_mir::monomorphize::collector::collect_items_rec::h5285a9621b2e0057 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#18 0x000000f6e81484ac in rustc_session::utils::_$LT$impl$u20$rustc_session..session..Session$GT$::time::h6270d26c32cbf11a ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#19 0x000000f6e7cb8494 in rustc_mir::monomorphize::collector::collect_crate_mono_items::hfbe7d399465ca039 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#20 0x000000f6e7cc478c in rustc_mir::monomorphize::partitioning::collect_and_partition_mono_items::h4ea486c19adc9420 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#21 0x000000f6e85b711c in rustc_query_system::query::plumbing::get_query_impl::hef92cc8e0e612213 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#22 0x000000f6e8b9f490 in _$LT$rustc_query_impl..Queries$u20$as$u20$rustc_middle..ty..query..QueryEngine$GT$::collect_and_partition_mono_items::hac6f01e7aca93579 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#23 0x000000f6e41b3be0 in rustc_codegen_ssa::base::codegen_crate::h3db3a6d60fd1c7d4 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#24 0x000000f6e41f5bd0 in _$LT$rustc_codegen_llvm..LlvmCodegenBackend$u20$as$u20$rustc_codegen_ssa..traits..backend..CodegenBackend$GT$::codegen_crate::h40fcbb02620c0c17 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#25 0x000000f6e3f9cc00 in rustc_interface::queries::Queries::ongoing_codegen::h7dc2980385cffc42 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#26 0x000000f6e3e42560 in rustc_interface::queries::_$LT$impl$u20$rustc_interface..interface..Compiler$GT$::enter::h90128beff5c4cd10 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#27 0x000000f6e3deb8e4 in rustc_span::with_source_map::hfaabe5aefc06fe09 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#28 0x000000f6e3e40128 in scoped_tls::ScopedKey$LT$T$GT$::set::h8d5d162635713055 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#29 0x000000f6e3ded9b8 in std::sys_common::backtrace::__rust_begin_short_backtrace::h2218f90c4db4ab67 ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#30 0x000000f6e3ddb1c8 in core::ops::function::FnOnce::call_once$u7b$$u7b$vtable.shim$u7d$$u7d$::hdc74afcb832c219f ()
   from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/librustc_driver-5418242a65cf926c.so
#31 0x000000f6e37ed5bc in std::sys::unix::thread::Thread::new::thread_start::h0daf8654cb819454 () from /home/semarie/repos/ports/pobj/rust-1.56.0/build-sparc64/build/sparc64-unknown-openbsd/stage1/lib/libstd-2f7fa7da8a3eb261.so
#32 0x000000f741a47490 in _rthread_start (v=0xf720080838) at /usr/src/lib/librthread/rthread.c:96
#33 0x000000f7207c58ac in __tfork_thread () at /usr/src/lib/libc/arch/sparc64/sys/tfork_thread.S:58
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

[semarie]

for reference, I am building natively on sparc64, with openbsd packaging infrastructure using this port tree (it is Makefile which is fetching 1.56.0, applies some patches, start build, package, etc...). It includes few patches.

I tested 1.55.0 on the exact same OS version and it built fine.

I am currently testing 1.56.0 without a patch I backported from 1.57.0 which is changing few bits on backtrace. The gdb backtrace has mention of std::sys_common::backtrace::__rust_begin_short_backtrace, so it might be good candidate for this breakage.

[semarie]

my build without gimli patch still fail. so it isn't that.

[apiraino]

Assigning priority as discussed in the Zulip thread of the Prioritization Working Group.

@rustbot label -I-prioritize +P-medium

[semarie]

I bisected the problem and it seems that it is started to appear with d488de8 (#87587). I am looking if I could go futher.

[semarie]

I made some progress.

Disabling C-unwind by removing the AbortUnwindingCalls pass (see #86155) helps to not trigger the double-free.

Regarding unwinding, on OpenBSD, all architectures doesn't do it the same way: specially, sparc64 is the sole to use libgcc instead of libunwind.

@alexcrichton do you have some possible pointers to help me to properly resolv the issue ? For now, I intent to add debug! calls inside AbortUnwindingCalls pass to help to localize the double-free.

[semarie]

@alexcrichton as a workaround (for a local patch for sparc64 on OpenBSD), does not calling AbortUnwindingCalls might lead to big problems ?