Cargo.toml

[package]
name = "mmtk"
version = "0.32.0"
authors = ["The MMTk Developers <>"]
edition = "2021" # TODO: Switch to 2024 after bumping MSRV to 1.85
license = "MIT OR Apache-2.0"
description = "MMTk is a framework for the design and implementation of high-performance and portable memory managers."
homepage = "https://www.mmtk.io"
repository = "https://github.com/mmtk/mmtk-core"
readme = "README.md"
categories = ["memory-management"]
keywords = ["gc", "garbage", "collection", "garbage-collection", "allocation"]
rust-version = "1.84"
build = "build.rs"
# Use the MSRV-aware resolver which has been available since Rust 1.84.
#
# NOTE: The MSRV-aware resolver will only find compatible versions within the allowed version range.
# For example, if we specify a dependency version as "0.7.2" or equivalently ">=0.7.2,<0.8.0",
# and the version 0.7.4 is MSRV-compatible but 0.7.5 is not, then it will resolve to 0.7.4.
# However, if 0.7.2 is not compatible with our MSRV,
# the resolver will refuse to go below 0.7.2, and the resolution will fail.
# For this reason, we still need to keep some dependency versions below the latest versions.
#
# TODO: Remove `resolver = "3"` after bumping Rust edition to 2024 (Rust 1.85+) because it will be the default.
resolver = "3"

[lib]
name = "mmtk"
crate-type = ["rlib"]
doctest = false

[dependencies]
# MMTk macros - we have to specify a version here in order to publish the crate, even though we use the dependency from a local path.
mmtk-macros = { version="0.32.0", path = "macros/" }

# Third party dependencies
atomic = "0.6.0"
atomic_refcell = "0.1.7"
atomic-traits = "0.4.0"
bytemuck = { version = "1.14.0", features = ["derive", "zeroable_maybe_uninit"] }
cfg-if = "1.0"
crossbeam = "0.8.1"
delegate = "0.13.2"
downcast-rs = "2.0.1"
enum-map = "2.7.3"
env_logger = { version = "0.11.3", optional = true }
is-terminal = "0.4.7"
itertools = "0.14.0"
jemalloc-sys = { version = "0.5.3", features = ["disable_initial_exec_tls"], optional = true }
lazy_static = "1.1"
libc = "0.2"
log = { version = "0.4", features = ["max_level_trace"] }
memoffset = "0.9"
mimalloc-sys = { version = "0.1.6", optional = true }
num_cpus = "1.8"
num-traits = "0.2"
pfm = { version = "0.1.1", optional = true }
portable-atomic = "1.4.3"
probe = "0.5"
regex = "1.7.0"
rustversion = "1.0"
spin = "0.10.0"
static_assertions = "1.1.0"
strum = "0.27.1"
strum_macros = "0.27.1"
# sysinfo >=0.37.0 requires MSRV 1.88.0 and Rust edition 2024.
sysinfo = "0.36.1"

[dev-dependencies]
paste = "1.0.8"
rand = "0.9.0"
rand_chacha = "0.9.0"
# criterion >=0.8.0 requires MSRV 1.86.0.
criterion = "0.7.0"

[build-dependencies]
built = { version = "0.8.0", features = ["git2"] }

[lints.clippy]
# Allow this. Clippy suggests we should use Sft, Mmtk, rather than SFT and MMTK.
# According to its documentation (https://rust-lang.github.io/rust-clippy/master/index.html#upper_case_acronyms),
# with upper-case-acronyms-aggressive turned on, it should also warn us about SFTMap, VMBinding, GCWorker.
# However, it seems clippy does not catch all these patterns at the moment. So it would be hard for us to
# find all the patterns and consistently change all of them. I think it would be a better idea to just allow this.
# We may reconsider this in the future. Plus, using upper case letters for acronyms does not sound a big issue
# to me - considering it will break our API and all the efforts for all the developers to make the change, it may
# not worth it.
upper_case_acronyms = "allow"
# Allow this -- 9 July 2025. Clippy suggests that we should always inline format args if possible.
# This lint was upgraded to 'style' in Rust 1.67, and then was downgraded to pedantic in 1.67.1.
# It was upgraded again in Rust 1.88, and downgraded again in Rust 1.89. We disable this lint to avoid warnings in affected versions.
# See https://github.com/mmtk/mmtk-core/issues/1334.
uninlined_format_args = "allow"

[[bench]]
name = "main"
harness = false

[features]
default = ["builtin_env_logger", "log/release_max_level_off"]

# Built-in env_logger.  This feature is enabled by default.
# The user can disable this default feature to remove `env_logger` from the dependencies.
# See `crate::util::logger` for more details.
builtin_env_logger = ["dep:env_logger"]

# Enable this feature if you want to use nightly features and compiler
nightly = []

# This feature is only supported on x86-64 for now
# It's manually added to CI scripts
perf_counter = ["dep:pfm"]

# This feature is only used for tests with MockVM.
# CI scripts run those tests with this feature.
mock_test = ["test_private"]

# This feature will expose some private functions for testings or benchmarking.
test_private = []

# .github/scripts/ci-common.sh extracts features from the following part (including from comments).
# So be careful when editing or adding stuff to the section below.


# Do not modify the following line - ci-common.sh matches it
# -- Non mutually exclusive features --

# spaces with different semantics

# A VM-allocated/managed space. A binding could use this for their boot image, metadata space, etc.
# FIXME: This is not properly implemented yet (it is only working for JikesRVM): https://github.com/mmtk/mmtk-core/issues/415
# If a binding would need to trace/scan objects that is allocated and managed by the VM, `ActivePlan::vm_trace_object()` is an alternative.
vm_space = []

# Bulk set unlog bits for all objects inside the VM space. A binding can use
# this in case they do not have a way to iterate through objects in the
# bootimage to set the unlog bit. Note that this will set the unlog bit for
# addresses that may not correspond to valid objects.
set_unlog_bits_vm_space = []

# A readonly space.
# TODO: This is not properly implemented yet. We currently use an immortal space instead, and do not guarantee read-only semantics.
ro_space = []
# A code space with execution permission.
code_space  = []

# By default, we only allow execution permission for code spaces. With this feature, all the spaces have execution permission.
# Use with care.
exec_permission_on_all_spaces = []

# Global valid object (VO) bit metadata.
# The VO bit is set when an object is allocated, and cleared when the GC determines it is dead.
# It is useful for conservative garbage collection, including conservative stack scanning.
# See `src/util/metadata/vo_bit/mod.rs`
#
# eager_sweeping: VO bits for dead objects must have been cleared by the end of each GC.
# Native MarkSweep only ensures this in eager sweeping mode.
vo_bit = ["eager_sweeping"]

# Enable object pinning, in particular, enable pinning/unpinning, and its metadata
object_pinning = []

# The following two features are useful for using Immix for VMs that do not support moving GC.

# Disable any object copying in Immix. This makes Immix a non-moving policy.
immix_non_moving = []

# Disable any object copying in nursery GC for Sticky Immix while allowing other kinds of copying.
# `immix_non_moving` disables all kinds of copying in Immix, so this feature is not needed
# if `immix_non_moving` is in use.
sticky_immix_non_moving_nursery = []

# Reduce block size for ImmixSpace.  This mitigates fragmentation when defrag is disabled.
immix_smaller_block = []
# Zero the unmarked lines after a GC cycle in immix. This helps debug untraced objects.
immix_zero_on_release = []

# Run sanity GC
sanity = []
# Run analysis
analysis = []
# Use lock free variant of NoGC
nogc_lock_free = []
# Use lock free with no zeroing NoGC
nogc_no_zeroing = ["nogc_lock_free"]
# For using a single GC thread
# Q: Why do we need this as a compile time flat? We can always set the number of GC threads through options.
single_worker = []

# To run expensive comprehensive runtime checks, such as checking duplicate edges
extreme_assertions = []

# Enable multiple spaces for NoGC, each allocator maps to an individual ImmortalSpace.
nogc_multi_space = []

# Disable multiple spaces for Compressor.
# Enabling this feature will cause the Compressor to move all objects, which will be
# slower for large objects and will be outright incorrect for bindings which allocate
# non-moving objects; but compacting all objects will be more space-efficient.
compressor_single_space = []

# To collect statistics for each GC work packet. Enabling this may introduce a small overhead (several percentage slowdown on benchmark time).
work_packet_stats = []

# Count the malloc'd memory into the heap size
malloc_counted_size = []

# Workaround a problem where bpftrace scripts (see tools/tracing/timeline/capture.bt) cannot
# capture the type names of work packets.
bpftrace_workaround = []

# Disable mmap annotations.
# All invocations of `mmap` in mmtk-core are accompanied by calls of `prctl` with
# `PR_SET_VMA_ANON_NAME` to annotate the mmap ranges with human-readable names.  It is enabled by
# default and should work fine even with large heap sizes.  However, if this is causing problems,
# users can disable such annotations by enabling this Cargo feature.
no_mmap_annotation = []

# Allow the binding to access Valid Object (VO) bit.
# MMTk uses VO bit to identify a valid object. Thus VO bit is carefully managed by MMTk in cooperation with the binding.
# So normally this feature is not needed, and its use should be discouraged.
# However, in rare cases, a binding may want to directly access and manipulate VO bit. For example, a binding cannot cooperate
# with MMTk to identify each object for setting the VO bit. This is usually due to the limitation of the VM.
# In such cases, a binding may use this feature and manipulate the VO bit to their needs. The binding's manipulation on VO bit
# may violate MMTk's semantics, and may result in undefined behaviors for VO bit related APIs. This feature should
# only be used if you understand how VO bit works internally. Use at your own risk.
vo_bit_access = []

# Do not modify the following line - ci-common.sh matches it
# -- Mutally exclusive features --
# Only one feature from each group can be provided. Otherwise build will fail.

# Name of the mutualy exclusive feature group. ci-common.sh matches lines like this one.
# Group:malloc
# only one of the following features should be enabled, or none to use the default malloc from libc
# this does not replace the global Rust allocator, but provides these libraries for GC implementation
malloc_mimalloc = ["dep:mimalloc-sys"]
malloc_jemalloc = ["dep:jemalloc-sys"]

# Use the native mimalloc allocator for malloc. This is not tested by me (Yi) yet, and it is only used to make sure that some code
# is not compiled in default builds.
malloc_native_mimalloc = []

# Group:marksweepallocation
# default is native allocator with lazy sweeping
eager_sweeping = []
# Use library malloc as the freelist allocator for mark sweep. This will makes mark sweep slower. As malloc may return addresses outside our
# normal heap range, we will have to use chunk-based SFT table. Turning on this feature will use a different SFT map implementation on 64bits,
# and will affect all the plans in the build. Please be aware of the consequence, and this is only meant to be experimental use.
malloc_mark_sweep = []

# Group:nonmovingspace
immortal_as_nonmoving = []
marksweep_as_nonmoving = []

# If there are more groups, they should be inserted above this line
# Group:end