wasmtime_cli_flags/
lib.rs

1//! Contains the common Wasmtime command line interface (CLI) flags.
2
3use anyhow::{Context, Result};
4use clap::Parser;
5use serde::Deserialize;
6use std::{
7    fmt, fs,
8    path::{Path, PathBuf},
9    time::Duration,
10};
11use wasmtime::Config;
12
13pub mod opt;
14
15#[cfg(feature = "logging")]
16fn init_file_per_thread_logger(prefix: &'static str) {
17    file_per_thread_logger::initialize(prefix);
18    file_per_thread_logger::allow_uninitialized();
19
20    // Extending behavior of default spawner:
21    // https://docs.rs/rayon/1.1.0/rayon/struct.ThreadPoolBuilder.html#method.spawn_handler
22    // Source code says DefaultSpawner is implementation detail and
23    // shouldn't be used directly.
24    #[cfg(feature = "parallel-compilation")]
25    rayon::ThreadPoolBuilder::new()
26        .spawn_handler(move |thread| {
27            let mut b = std::thread::Builder::new();
28            if let Some(name) = thread.name() {
29                b = b.name(name.to_owned());
30            }
31            if let Some(stack_size) = thread.stack_size() {
32                b = b.stack_size(stack_size);
33            }
34            b.spawn(move || {
35                file_per_thread_logger::initialize(prefix);
36                thread.run()
37            })?;
38            Ok(())
39        })
40        .build_global()
41        .unwrap();
42}
43
44wasmtime_option_group! {
45    #[derive(PartialEq, Clone, Deserialize)]
46    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
47    pub struct OptimizeOptions {
48        /// Optimization level of generated code (0-2, s; default: 2)
49        #[serde(default)]
50        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
51        pub opt_level: Option<wasmtime::OptLevel>,
52
53        /// Register allocator algorithm choice.
54        #[serde(default)]
55        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
56        pub regalloc_algorithm: Option<wasmtime::RegallocAlgorithm>,
57
58        /// Do not allow Wasm linear memories to move in the host process's
59        /// address space.
60        pub memory_may_move: Option<bool>,
61
62        /// Initial virtual memory allocation size for memories.
63        pub memory_reservation: Option<u64>,
64
65        /// Bytes to reserve at the end of linear memory for growth into.
66        pub memory_reservation_for_growth: Option<u64>,
67
68        /// Size, in bytes, of guard pages for linear memories.
69        pub memory_guard_size: Option<u64>,
70
71        /// Indicates whether an unmapped region of memory is placed before all
72        /// linear memories.
73        pub guard_before_linear_memory: Option<bool>,
74
75        /// Whether to initialize tables lazily, so that instantiation is
76        /// fast but indirect calls are a little slower. If no, tables are
77        /// initialized eagerly from any active element segments that apply to
78        /// them during instantiation. (default: yes)
79        pub table_lazy_init: Option<bool>,
80
81        /// Enable the pooling allocator, in place of the on-demand allocator.
82        pub pooling_allocator: Option<bool>,
83
84        /// The number of decommits to do per batch. A batch size of 1
85        /// effectively disables decommit batching. (default: 1)
86        pub pooling_decommit_batch_size: Option<usize>,
87
88        /// How many bytes to keep resident between instantiations for the
89        /// pooling allocator in linear memories.
90        pub pooling_memory_keep_resident: Option<usize>,
91
92        /// How many bytes to keep resident between instantiations for the
93        /// pooling allocator in tables.
94        pub pooling_table_keep_resident: Option<usize>,
95
96        /// Enable memory protection keys for the pooling allocator; this can
97        /// optimize the size of memory slots.
98        #[serde(default)]
99        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
100        pub pooling_memory_protection_keys: Option<wasmtime::Enabled>,
101
102        /// Sets an upper limit on how many memory protection keys (MPK) Wasmtime
103        /// will use. (default: 16)
104        pub pooling_max_memory_protection_keys: Option<usize>,
105
106        /// Configure attempting to initialize linear memory via a
107        /// copy-on-write mapping (default: yes)
108        pub memory_init_cow: Option<bool>,
109
110        /// Threshold below which CoW images are guaranteed to be used and be
111        /// dense.
112        pub memory_guaranteed_dense_image_size: Option<u64>,
113
114        /// The maximum number of WebAssembly instances which can be created
115        /// with the pooling allocator.
116        pub pooling_total_core_instances: Option<u32>,
117
118        /// The maximum number of WebAssembly components which can be created
119        /// with the pooling allocator.
120        pub pooling_total_component_instances: Option<u32>,
121
122        /// The maximum number of WebAssembly memories which can be created with
123        /// the pooling allocator.
124        pub pooling_total_memories: Option<u32>,
125
126        /// The maximum number of WebAssembly tables which can be created with
127        /// the pooling allocator.
128        pub pooling_total_tables: Option<u32>,
129
130        /// The maximum number of WebAssembly stacks which can be created with
131        /// the pooling allocator.
132        pub pooling_total_stacks: Option<u32>,
133
134        /// The maximum runtime size of each linear memory in the pooling
135        /// allocator, in bytes.
136        pub pooling_max_memory_size: Option<usize>,
137
138        /// The maximum table elements for any table defined in a module when
139        /// using the pooling allocator.
140        pub pooling_table_elements: Option<usize>,
141
142        /// The maximum size, in bytes, allocated for a core instance's metadata
143        /// when using the pooling allocator.
144        pub pooling_max_core_instance_size: Option<usize>,
145
146        /// Configures the maximum number of "unused warm slots" to retain in the
147        /// pooling allocator. (default: 100)
148        pub pooling_max_unused_warm_slots: Option<u32>,
149
150        /// How much memory, in bytes, to keep resident for async stacks allocated
151        /// with the pooling allocator. (default: 0)
152        pub pooling_async_stack_keep_resident: Option<usize>,
153
154        /// The maximum size, in bytes, allocated for a component instance's
155        /// `VMComponentContext` metadata. (default: 1MiB)
156        pub pooling_max_component_instance_size: Option<usize>,
157
158        /// The maximum number of core instances a single component may contain
159        /// (default is unlimited).
160        pub pooling_max_core_instances_per_component: Option<u32>,
161
162        /// The maximum number of Wasm linear memories that a single component may
163        /// transitively contain (default is unlimited).
164        pub pooling_max_memories_per_component: Option<u32>,
165
166        /// The maximum number of tables that a single component may transitively
167        /// contain (default is unlimited).
168        pub pooling_max_tables_per_component: Option<u32>,
169
170        /// The maximum number of defined tables for a core module. (default: 1)
171        pub pooling_max_tables_per_module: Option<u32>,
172
173        /// The maximum number of defined linear memories for a module. (default: 1)
174        pub pooling_max_memories_per_module: Option<u32>,
175
176        /// The maximum number of concurrent GC heaps supported. (default: 1000)
177        pub pooling_total_gc_heaps: Option<u32>,
178
179        /// Enable or disable the use of host signal handlers for traps.
180        pub signals_based_traps: Option<bool>,
181
182        /// DEPRECATED: Use `-Cmemory-guard-size=N` instead.
183        pub dynamic_memory_guard_size: Option<u64>,
184
185        /// DEPRECATED: Use `-Cmemory-guard-size=N` instead.
186        pub static_memory_guard_size: Option<u64>,
187
188        /// DEPRECATED: Use `-Cmemory-may-move` instead.
189        pub static_memory_forced: Option<bool>,
190
191        /// DEPRECATED: Use `-Cmemory-reservation=N` instead.
192        pub static_memory_maximum_size: Option<u64>,
193
194        /// DEPRECATED: Use `-Cmemory-reservation-for-growth=N` instead.
195        pub dynamic_memory_reserved_for_growth: Option<u64>,
196
197        /// Whether or not `PAGEMAP_SCAN` ioctls are used to reset linear
198        /// memory.
199        #[serde(default)]
200        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
201        pub pooling_pagemap_scan: Option<wasmtime::Enabled>,
202    }
203
204    enum Optimize {
205        ...
206    }
207}
208
209wasmtime_option_group! {
210    #[derive(PartialEq, Clone, Deserialize)]
211    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
212    pub struct CodegenOptions {
213        /// Either `cranelift` or `winch`.
214        ///
215        /// Currently only `cranelift` and `winch` are supported, but not all
216        /// builds of Wasmtime have both built in.
217        #[serde(default)]
218        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
219        pub compiler: Option<wasmtime::Strategy>,
220        /// Which garbage collector to use: `drc` or `null`.
221        ///
222        /// `drc` is the deferred reference-counting collector.
223        ///
224        /// `null` is the null garbage collector, which does not collect any
225        /// garbage.
226        ///
227        /// Note that not all builds of Wasmtime will have support for garbage
228        /// collection included.
229        #[serde(default)]
230        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
231        pub collector: Option<wasmtime::Collector>,
232        /// Enable Cranelift's internal debug verifier (expensive)
233        pub cranelift_debug_verifier: Option<bool>,
234        /// Whether or not to enable caching of compiled modules.
235        pub cache: Option<bool>,
236        /// Configuration for compiled module caching.
237        pub cache_config: Option<String>,
238        /// Whether or not to enable parallel compilation of modules.
239        pub parallel_compilation: Option<bool>,
240        /// Whether to enable proof-carrying code (PCC)-based validation.
241        pub pcc: Option<bool>,
242        /// Controls whether native unwind information is present in compiled
243        /// object files.
244        pub native_unwind_info: Option<bool>,
245
246        /// Whether to perform function inlining during compilation.
247        pub inlining: Option<bool>,
248
249        #[prefixed = "cranelift"]
250        #[serde(default)]
251        /// Set a cranelift-specific option. Use `wasmtime settings` to see
252        /// all.
253        pub cranelift: Vec<(String, Option<String>)>,
254    }
255
256    enum Codegen {
257        ...
258    }
259}
260
261wasmtime_option_group! {
262    #[derive(PartialEq, Clone, Deserialize)]
263    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
264    pub struct DebugOptions {
265        /// Enable generation of DWARF debug information in compiled code.
266        pub debug_info: Option<bool>,
267        /// Enable guest debugging insrumentation.
268        pub guest_debug: Option<bool>,
269        /// Configure whether compiled code can map native addresses to wasm.
270        pub address_map: Option<bool>,
271        /// Configure whether logging is enabled.
272        pub logging: Option<bool>,
273        /// Configure whether logs are emitted to files
274        pub log_to_files: Option<bool>,
275        /// Enable coredump generation to this file after a WebAssembly trap.
276        pub coredump: Option<String>,
277    }
278
279    enum Debug {
280        ...
281    }
282}
283
284wasmtime_option_group! {
285    #[derive(PartialEq, Clone, Deserialize)]
286    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
287    pub struct WasmOptions {
288        /// Enable canonicalization of all NaN values.
289        pub nan_canonicalization: Option<bool>,
290        /// Enable execution fuel with N units fuel, trapping after running out
291        /// of fuel.
292        ///
293        /// Most WebAssembly instructions consume 1 unit of fuel. Some
294        /// instructions, such as `nop`, `drop`, `block`, and `loop`, consume 0
295        /// units, as any execution cost associated with them involves other
296        /// instructions which do consume fuel.
297        pub fuel: Option<u64>,
298        /// Yield when a global epoch counter changes, allowing for async
299        /// operation without blocking the executor.
300        pub epoch_interruption: Option<bool>,
301        /// Maximum stack size, in bytes, that wasm is allowed to consume before a
302        /// stack overflow is reported.
303        pub max_wasm_stack: Option<usize>,
304        /// Stack size, in bytes, that will be allocated for async stacks.
305        ///
306        /// Note that this must be larger than `max-wasm-stack` and the
307        /// difference between the two is how much stack the host has to execute
308        /// on.
309        pub async_stack_size: Option<usize>,
310        /// Configures whether or not stacks used for async futures are zeroed
311        /// before (re)use as a defense-in-depth mechanism. (default: false)
312        pub async_stack_zeroing: Option<bool>,
313        /// Allow unknown exports when running commands.
314        pub unknown_exports_allow: Option<bool>,
315        /// Allow the main module to import unknown functions, using an
316        /// implementation that immediately traps, when running commands.
317        pub unknown_imports_trap: Option<bool>,
318        /// Allow the main module to import unknown functions, using an
319        /// implementation that returns default values, when running commands.
320        pub unknown_imports_default: Option<bool>,
321        /// Enables memory error checking. (see wmemcheck.md for more info)
322        pub wmemcheck: Option<bool>,
323        /// Maximum size, in bytes, that a linear memory is allowed to reach.
324        ///
325        /// Growth beyond this limit will cause `memory.grow` instructions in
326        /// WebAssembly modules to return -1 and fail.
327        pub max_memory_size: Option<usize>,
328        /// Maximum size, in table elements, that a table is allowed to reach.
329        pub max_table_elements: Option<usize>,
330        /// Maximum number of WebAssembly instances allowed to be created.
331        pub max_instances: Option<usize>,
332        /// Maximum number of WebAssembly tables allowed to be created.
333        pub max_tables: Option<usize>,
334        /// Maximum number of WebAssembly linear memories allowed to be created.
335        pub max_memories: Option<usize>,
336        /// Force a trap to be raised on `memory.grow` and `table.grow` failure
337        /// instead of returning -1 from these instructions.
338        ///
339        /// This is not necessarily a spec-compliant option to enable but can be
340        /// useful for tracking down a backtrace of what is requesting so much
341        /// memory, for example.
342        pub trap_on_grow_failure: Option<bool>,
343        /// Maximum execution time of wasm code before timing out (1, 2s, 100ms, etc)
344        pub timeout: Option<Duration>,
345        /// Configures support for all WebAssembly proposals implemented.
346        pub all_proposals: Option<bool>,
347        /// Configure support for the bulk memory proposal.
348        pub bulk_memory: Option<bool>,
349        /// Configure support for the multi-memory proposal.
350        pub multi_memory: Option<bool>,
351        /// Configure support for the multi-value proposal.
352        pub multi_value: Option<bool>,
353        /// Configure support for the reference-types proposal.
354        pub reference_types: Option<bool>,
355        /// Configure support for the simd proposal.
356        pub simd: Option<bool>,
357        /// Configure support for the relaxed-simd proposal.
358        pub relaxed_simd: Option<bool>,
359        /// Configure forcing deterministic and host-independent behavior of
360        /// the relaxed-simd instructions.
361        ///
362        /// By default these instructions may have architecture-specific behavior as
363        /// allowed by the specification, but this can be used to force the behavior
364        /// of these instructions to match the deterministic behavior classified in
365        /// the specification. Note that enabling this option may come at a
366        /// performance cost.
367        pub relaxed_simd_deterministic: Option<bool>,
368        /// Configure support for the tail-call proposal.
369        pub tail_call: Option<bool>,
370        /// Configure support for the threads proposal.
371        pub threads: Option<bool>,
372        /// Configure support for the shared-everything-threads proposal.
373        pub shared_everything_threads: Option<bool>,
374        /// Configure support for the memory64 proposal.
375        pub memory64: Option<bool>,
376        /// Configure support for the component-model proposal.
377        pub component_model: Option<bool>,
378        /// Component model support for async lifting/lowering.
379        pub component_model_async: Option<bool>,
380        /// Component model support for async lifting/lowering: this corresponds
381        /// to the 🚝 emoji in the component model specification.
382        pub component_model_async_builtins: Option<bool>,
383        /// Component model support for async lifting/lowering: this corresponds
384        /// to the 🚟 emoji in the component model specification.
385        pub component_model_async_stackful: Option<bool>,
386        /// Component model support for threading: this corresponds
387        /// to the 🧵 emoji in the component model specification.
388        pub component_model_threading: Option<bool>,
389        /// Component model support for `error-context`: this corresponds
390        /// to the 📝 emoji in the component model specification.
391        pub component_model_error_context: Option<bool>,
392        /// GC support in the component model: this corresponds to the 🛸 emoji
393        /// in the component model specification.
394        pub component_model_gc: Option<bool>,
395        /// Configure support for the function-references proposal.
396        pub function_references: Option<bool>,
397        /// Configure support for the stack-switching proposal.
398        pub stack_switching: Option<bool>,
399        /// Configure support for the GC proposal.
400        pub gc: Option<bool>,
401        /// Configure support for the custom-page-sizes proposal.
402        pub custom_page_sizes: Option<bool>,
403        /// Configure support for the wide-arithmetic proposal.
404        pub wide_arithmetic: Option<bool>,
405        /// Configure support for the extended-const proposal.
406        pub extended_const: Option<bool>,
407        /// Configure support for the exceptions proposal.
408        pub exceptions: Option<bool>,
409        /// Whether or not any GC infrastructure in Wasmtime is enabled or not.
410        pub gc_support: Option<bool>,
411    }
412
413    enum Wasm {
414        ...
415    }
416}
417
418wasmtime_option_group! {
419    #[derive(PartialEq, Clone, Deserialize)]
420    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
421    pub struct WasiOptions {
422        /// Enable support for WASI CLI APIs, including filesystems, sockets, clocks, and random.
423        pub cli: Option<bool>,
424        /// Enable WASI APIs marked as: @unstable(feature = cli-exit-with-code)
425        pub cli_exit_with_code: Option<bool>,
426        /// Deprecated alias for `cli`
427        pub common: Option<bool>,
428        /// Enable support for WASI neural network imports (experimental)
429        pub nn: Option<bool>,
430        /// Enable support for WASI threading imports (experimental). Implies preview2=false.
431        pub threads: Option<bool>,
432        /// Enable support for WASI HTTP imports
433        pub http: Option<bool>,
434        /// Number of distinct write calls to the outgoing body's output-stream
435        /// that the implementation will buffer.
436        /// Default: 1.
437        pub http_outgoing_body_buffer_chunks: Option<usize>,
438        /// Maximum size allowed in a write call to the outgoing body's output-stream.
439        /// Default: 1024 * 1024.
440        pub http_outgoing_body_chunk_size: Option<usize>,
441        /// Enable support for WASI config imports (experimental)
442        pub config: Option<bool>,
443        /// Enable support for WASI key-value imports (experimental)
444        pub keyvalue: Option<bool>,
445        /// Inherit environment variables and file descriptors following the
446        /// systemd listen fd specification (UNIX only) (legacy wasip1
447        /// implementation only)
448        pub listenfd: Option<bool>,
449        /// Grant access to the given TCP listen socket (experimental, legacy
450        /// wasip1 implementation only)
451        #[serde(default)]
452        pub tcplisten: Vec<String>,
453        /// Enable support for WASI TLS (Transport Layer Security) imports (experimental)
454        pub tls: Option<bool>,
455        /// Implement WASI Preview1 using new Preview2 implementation (true, default) or legacy
456        /// implementation (false)
457        pub preview2: Option<bool>,
458        /// Pre-load machine learning graphs (i.e., models) for use by wasi-nn.
459        ///
460        /// Each use of the flag will preload a ML model from the host directory
461        /// using the given model encoding. The model will be mapped to the
462        /// directory name: e.g., `--wasi-nn-graph openvino:/foo/bar` will preload
463        /// an OpenVINO model named `bar`. Note that which model encodings are
464        /// available is dependent on the backends implemented in the
465        /// `wasmtime_wasi_nn` crate.
466        #[serde(skip)]
467        pub nn_graph: Vec<WasiNnGraph>,
468        /// Flag for WASI preview2 to inherit the host's network within the
469        /// guest so it has full access to all addresses/ports/etc.
470        pub inherit_network: Option<bool>,
471        /// Indicates whether `wasi:sockets/ip-name-lookup` is enabled or not.
472        pub allow_ip_name_lookup: Option<bool>,
473        /// Indicates whether `wasi:sockets` TCP support is enabled or not.
474        pub tcp: Option<bool>,
475        /// Indicates whether `wasi:sockets` UDP support is enabled or not.
476        pub udp: Option<bool>,
477        /// Enable WASI APIs marked as: @unstable(feature = network-error-code)
478        pub network_error_code: Option<bool>,
479        /// Allows imports from the `wasi_unstable` core wasm module.
480        pub preview0: Option<bool>,
481        /// Inherit all environment variables from the parent process.
482        ///
483        /// This option can be further overwritten with `--env` flags.
484        pub inherit_env: Option<bool>,
485        /// Pass a wasi config variable to the program.
486        #[serde(skip)]
487        pub config_var: Vec<KeyValuePair>,
488        /// Preset data for the In-Memory provider of WASI key-value API.
489        #[serde(skip)]
490        pub keyvalue_in_memory_data: Vec<KeyValuePair>,
491        /// Enable support for WASIp3 APIs.
492        pub p3: Option<bool>,
493    }
494
495    enum Wasi {
496        ...
497    }
498}
499
500#[derive(Debug, Clone, PartialEq)]
501pub struct WasiNnGraph {
502    pub format: String,
503    pub dir: String,
504}
505
506#[derive(Debug, Clone, PartialEq)]
507pub struct KeyValuePair {
508    pub key: String,
509    pub value: String,
510}
511
512/// Common options for commands that translate WebAssembly modules
513#[derive(Parser, Clone, Deserialize)]
514#[serde(deny_unknown_fields)]
515pub struct CommonOptions {
516    // These options groups are used to parse `-O` and such options but aren't
517    // the raw form consumed by the CLI. Instead they're pushed into the `pub`
518    // fields below as part of the `configure` method.
519    //
520    // Ideally clap would support `pub opts: OptimizeOptions` and parse directly
521    // into that but it does not appear to do so for multiple `-O` flags for
522    // now.
523    /// Optimization and tuning related options for wasm performance, `-O help` to
524    /// see all.
525    #[arg(short = 'O', long = "optimize", value_name = "KEY[=VAL[,..]]")]
526    #[serde(skip)]
527    opts_raw: Vec<opt::CommaSeparated<Optimize>>,
528
529    /// Codegen-related configuration options, `-C help` to see all.
530    #[arg(short = 'C', long = "codegen", value_name = "KEY[=VAL[,..]]")]
531    #[serde(skip)]
532    codegen_raw: Vec<opt::CommaSeparated<Codegen>>,
533
534    /// Debug-related configuration options, `-D help` to see all.
535    #[arg(short = 'D', long = "debug", value_name = "KEY[=VAL[,..]]")]
536    #[serde(skip)]
537    debug_raw: Vec<opt::CommaSeparated<Debug>>,
538
539    /// Options for configuring semantic execution of WebAssembly, `-W help` to see
540    /// all.
541    #[arg(short = 'W', long = "wasm", value_name = "KEY[=VAL[,..]]")]
542    #[serde(skip)]
543    wasm_raw: Vec<opt::CommaSeparated<Wasm>>,
544
545    /// Options for configuring WASI and its proposals, `-S help` to see all.
546    #[arg(short = 'S', long = "wasi", value_name = "KEY[=VAL[,..]]")]
547    #[serde(skip)]
548    wasi_raw: Vec<opt::CommaSeparated<Wasi>>,
549
550    // These fields are filled in by the `configure` method below via the
551    // options parsed from the CLI above. This is what the CLI should use.
552    #[arg(skip)]
553    #[serde(skip)]
554    configured: bool,
555
556    #[arg(skip)]
557    #[serde(rename = "optimize", default)]
558    pub opts: OptimizeOptions,
559
560    #[arg(skip)]
561    #[serde(rename = "codegen", default)]
562    pub codegen: CodegenOptions,
563
564    #[arg(skip)]
565    #[serde(rename = "debug", default)]
566    pub debug: DebugOptions,
567
568    #[arg(skip)]
569    #[serde(rename = "wasm", default)]
570    pub wasm: WasmOptions,
571
572    #[arg(skip)]
573    #[serde(rename = "wasi", default)]
574    pub wasi: WasiOptions,
575
576    /// The target triple; default is the host triple
577    #[arg(long, value_name = "TARGET")]
578    #[serde(skip)]
579    pub target: Option<String>,
580
581    /// Use the specified TOML configuration file.
582    /// This TOML configuration file can provide same configuration options as the
583    /// `--optimize`, `--codgen`, `--debug`, `--wasm`, `--wasi` CLI options, with a couple exceptions.
584    ///
585    /// Additional options specified on the command line will take precedent over options loaded from
586    /// this TOML file.
587    #[arg(long = "config", value_name = "FILE")]
588    #[serde(skip)]
589    pub config: Option<PathBuf>,
590}
591
592macro_rules! match_feature {
593    (
594        [$feat:tt : $config:expr]
595        $val:ident => $e:expr,
596        $p:pat => err,
597    ) => {
598        #[cfg(feature = $feat)]
599        {
600            if let Some($val) = $config {
601                $e;
602            }
603        }
604        #[cfg(not(feature = $feat))]
605        {
606            if let Some($p) = $config {
607                anyhow::bail!(concat!("support for ", $feat, " disabled at compile time"));
608            }
609        }
610    };
611}
612
613impl CommonOptions {
614    /// Creates a blank new set of [`CommonOptions`] that can be configured.
615    pub fn new() -> CommonOptions {
616        CommonOptions {
617            opts_raw: Vec::new(),
618            codegen_raw: Vec::new(),
619            debug_raw: Vec::new(),
620            wasm_raw: Vec::new(),
621            wasi_raw: Vec::new(),
622            configured: true,
623            opts: Default::default(),
624            codegen: Default::default(),
625            debug: Default::default(),
626            wasm: Default::default(),
627            wasi: Default::default(),
628            target: None,
629            config: None,
630        }
631    }
632
633    fn configure(&mut self) -> Result<()> {
634        if self.configured {
635            return Ok(());
636        }
637        self.configured = true;
638        if let Some(toml_config_path) = &self.config {
639            let toml_options = CommonOptions::from_file(toml_config_path)?;
640            self.opts = toml_options.opts;
641            self.codegen = toml_options.codegen;
642            self.debug = toml_options.debug;
643            self.wasm = toml_options.wasm;
644            self.wasi = toml_options.wasi;
645        }
646        self.opts.configure_with(&self.opts_raw);
647        self.codegen.configure_with(&self.codegen_raw);
648        self.debug.configure_with(&self.debug_raw);
649        self.wasm.configure_with(&self.wasm_raw);
650        self.wasi.configure_with(&self.wasi_raw);
651        Ok(())
652    }
653
654    pub fn init_logging(&mut self) -> Result<()> {
655        self.configure()?;
656        if self.debug.logging == Some(false) {
657            return Ok(());
658        }
659        #[cfg(feature = "logging")]
660        if self.debug.log_to_files == Some(true) {
661            let prefix = "wasmtime.dbg.";
662            init_file_per_thread_logger(prefix);
663        } else {
664            use std::io::IsTerminal;
665            use tracing_subscriber::{EnvFilter, FmtSubscriber};
666            let builder = FmtSubscriber::builder()
667                .with_writer(std::io::stderr)
668                .with_env_filter(EnvFilter::from_env("WASMTIME_LOG"))
669                .with_ansi(std::io::stderr().is_terminal());
670            if std::env::var("WASMTIME_LOG_NO_CONTEXT").is_ok_and(|value| value.eq("1")) {
671                builder
672                    .with_level(false)
673                    .with_target(false)
674                    .without_time()
675                    .init()
676            } else {
677                builder.init();
678            }
679        }
680        #[cfg(not(feature = "logging"))]
681        if self.debug.log_to_files == Some(true) || self.debug.logging == Some(true) {
682            anyhow::bail!("support for logging disabled at compile time");
683        }
684        Ok(())
685    }
686
687    pub fn config(&mut self, pooling_allocator_default: Option<bool>) -> Result<Config> {
688        self.configure()?;
689        let mut config = Config::new();
690
691        match_feature! {
692            ["cranelift" : self.codegen.compiler]
693            strategy => config.strategy(strategy),
694            _ => err,
695        }
696        match_feature! {
697            ["gc" : self.codegen.collector]
698            collector => config.collector(collector),
699            _ => err,
700        }
701        if let Some(target) = &self.target {
702            config.target(target)?;
703        }
704        match_feature! {
705            ["cranelift" : self.codegen.cranelift_debug_verifier]
706            enable => config.cranelift_debug_verifier(enable),
707            true => err,
708        }
709        if let Some(enable) = self.debug.debug_info {
710            config.debug_info(enable);
711        }
712        match_feature! {
713            ["debug" : self.debug.guest_debug]
714            enable => config.guest_debug(enable),
715            _ => err,
716        }
717        if self.debug.coredump.is_some() {
718            #[cfg(feature = "coredump")]
719            config.coredump_on_trap(true);
720            #[cfg(not(feature = "coredump"))]
721            anyhow::bail!("support for coredumps disabled at compile time");
722        }
723        match_feature! {
724            ["cranelift" : self.opts.opt_level]
725            level => config.cranelift_opt_level(level),
726            _ => err,
727        }
728        match_feature! {
729            ["cranelift": self.opts.regalloc_algorithm]
730            algo => config.cranelift_regalloc_algorithm(algo),
731            _ => err,
732        }
733        match_feature! {
734            ["cranelift" : self.wasm.nan_canonicalization]
735            enable => config.cranelift_nan_canonicalization(enable),
736            true => err,
737        }
738        match_feature! {
739            ["cranelift" : self.codegen.pcc]
740            enable => config.cranelift_pcc(enable),
741            true => err,
742        }
743
744        self.enable_wasm_features(&mut config)?;
745
746        #[cfg(feature = "cranelift")]
747        for (name, value) in self.codegen.cranelift.iter() {
748            let name = name.replace('-', "_");
749            unsafe {
750                match value {
751                    Some(val) => {
752                        config.cranelift_flag_set(&name, val);
753                    }
754                    None => {
755                        config.cranelift_flag_enable(&name);
756                    }
757                }
758            }
759        }
760        #[cfg(not(feature = "cranelift"))]
761        if !self.codegen.cranelift.is_empty() {
762            anyhow::bail!("support for cranelift disabled at compile time");
763        }
764
765        #[cfg(feature = "cache")]
766        if self.codegen.cache != Some(false) {
767            use wasmtime::Cache;
768            let cache = match &self.codegen.cache_config {
769                Some(path) => Cache::from_file(Some(Path::new(path)))?,
770                None => Cache::from_file(None)?,
771            };
772            config.cache(Some(cache));
773        }
774        #[cfg(not(feature = "cache"))]
775        if self.codegen.cache == Some(true) {
776            anyhow::bail!("support for caching disabled at compile time");
777        }
778
779        match_feature! {
780            ["parallel-compilation" : self.codegen.parallel_compilation]
781            enable => config.parallel_compilation(enable),
782            true => err,
783        }
784
785        let memory_reservation = self
786            .opts
787            .memory_reservation
788            .or(self.opts.static_memory_maximum_size);
789        if let Some(size) = memory_reservation {
790            config.memory_reservation(size);
791        }
792
793        if let Some(enable) = self.opts.static_memory_forced {
794            config.memory_may_move(!enable);
795        }
796        if let Some(enable) = self.opts.memory_may_move {
797            config.memory_may_move(enable);
798        }
799
800        let memory_guard_size = self
801            .opts
802            .static_memory_guard_size
803            .or(self.opts.dynamic_memory_guard_size)
804            .or(self.opts.memory_guard_size);
805        if let Some(size) = memory_guard_size {
806            config.memory_guard_size(size);
807        }
808
809        let mem_for_growth = self
810            .opts
811            .memory_reservation_for_growth
812            .or(self.opts.dynamic_memory_reserved_for_growth);
813        if let Some(size) = mem_for_growth {
814            config.memory_reservation_for_growth(size);
815        }
816        if let Some(enable) = self.opts.guard_before_linear_memory {
817            config.guard_before_linear_memory(enable);
818        }
819        if let Some(enable) = self.opts.table_lazy_init {
820            config.table_lazy_init(enable);
821        }
822
823        // If fuel has been configured, set the `consume fuel` flag on the config.
824        if self.wasm.fuel.is_some() {
825            config.consume_fuel(true);
826        }
827
828        if let Some(enable) = self.wasm.epoch_interruption {
829            config.epoch_interruption(enable);
830        }
831        if let Some(enable) = self.debug.address_map {
832            config.generate_address_map(enable);
833        }
834        if let Some(enable) = self.opts.memory_init_cow {
835            config.memory_init_cow(enable);
836        }
837        if let Some(size) = self.opts.memory_guaranteed_dense_image_size {
838            config.memory_guaranteed_dense_image_size(size);
839        }
840        if let Some(enable) = self.opts.signals_based_traps {
841            config.signals_based_traps(enable);
842        }
843        if let Some(enable) = self.codegen.native_unwind_info {
844            config.native_unwind_info(enable);
845        }
846        if let Some(enable) = self.codegen.inlining {
847            config.compiler_inlining(enable);
848        }
849
850        // async_stack_size enabled by either async or stack-switching, so
851        // cannot directly use match_feature!
852        #[cfg(any(feature = "async", feature = "stack-switching"))]
853        {
854            if let Some(size) = self.wasm.async_stack_size {
855                config.async_stack_size(size);
856            }
857        }
858        #[cfg(not(any(feature = "async", feature = "stack-switching")))]
859        {
860            if let Some(_size) = self.wasm.async_stack_size {
861                anyhow::bail!(concat!(
862                    "support for async/stack-switching disabled at compile time"
863                ));
864            }
865        }
866
867        match_feature! {
868            ["pooling-allocator" : self.opts.pooling_allocator.or(pooling_allocator_default)]
869            enable => {
870                if enable {
871                    let mut cfg = wasmtime::PoolingAllocationConfig::default();
872                    if let Some(size) = self.opts.pooling_memory_keep_resident {
873                        cfg.linear_memory_keep_resident(size);
874                    }
875                    if let Some(size) = self.opts.pooling_table_keep_resident {
876                        cfg.table_keep_resident(size);
877                    }
878                    if let Some(limit) = self.opts.pooling_total_core_instances {
879                        cfg.total_core_instances(limit);
880                    }
881                    if let Some(limit) = self.opts.pooling_total_component_instances {
882                        cfg.total_component_instances(limit);
883                    }
884                    if let Some(limit) = self.opts.pooling_total_memories {
885                        cfg.total_memories(limit);
886                    }
887                    if let Some(limit) = self.opts.pooling_total_tables {
888                        cfg.total_tables(limit);
889                    }
890                    if let Some(limit) = self.opts.pooling_table_elements
891                        .or(self.wasm.max_table_elements)
892                    {
893                        cfg.table_elements(limit);
894                    }
895                    if let Some(limit) = self.opts.pooling_max_core_instance_size {
896                        cfg.max_core_instance_size(limit);
897                    }
898                    match_feature! {
899                        ["async" : self.opts.pooling_total_stacks]
900                        limit => cfg.total_stacks(limit),
901                        _ => err,
902                    }
903                    if let Some(max) = self.opts.pooling_max_memory_size
904                        .or(self.wasm.max_memory_size)
905                    {
906                        cfg.max_memory_size(max);
907                    }
908                    if let Some(size) = self.opts.pooling_decommit_batch_size {
909                        cfg.decommit_batch_size(size);
910                    }
911                    if let Some(max) = self.opts.pooling_max_unused_warm_slots {
912                        cfg.max_unused_warm_slots(max);
913                    }
914                    match_feature! {
915                        ["async" : self.opts.pooling_async_stack_keep_resident]
916                        size => cfg.async_stack_keep_resident(size),
917                        _ => err,
918                    }
919                    if let Some(max) = self.opts.pooling_max_component_instance_size {
920                        cfg.max_component_instance_size(max);
921                    }
922                    if let Some(max) = self.opts.pooling_max_core_instances_per_component {
923                        cfg.max_core_instances_per_component(max);
924                    }
925                    if let Some(max) = self.opts.pooling_max_memories_per_component {
926                        cfg.max_memories_per_component(max);
927                    }
928                    if let Some(max) = self.opts.pooling_max_tables_per_component {
929                        cfg.max_tables_per_component(max);
930                    }
931                    if let Some(max) = self.opts.pooling_max_tables_per_module {
932                        cfg.max_tables_per_module(max);
933                    }
934                    if let Some(max) = self.opts.pooling_max_memories_per_module {
935                        cfg.max_memories_per_module(max);
936                    }
937                    match_feature! {
938                        ["memory-protection-keys" : self.opts.pooling_memory_protection_keys]
939                        enable => cfg.memory_protection_keys(enable),
940                        _ => err,
941                    }
942                    match_feature! {
943                        ["memory-protection-keys" : self.opts.pooling_max_memory_protection_keys]
944                        max => cfg.max_memory_protection_keys(max),
945                        _ => err,
946                    }
947                    match_feature! {
948                        ["gc" : self.opts.pooling_total_gc_heaps]
949                        max => cfg.total_gc_heaps(max),
950                        _ => err,
951                    }
952                    if let Some(enabled) = self.opts.pooling_pagemap_scan {
953                        cfg.pagemap_scan(enabled);
954                    }
955                    config.allocation_strategy(wasmtime::InstanceAllocationStrategy::Pooling(cfg));
956                }
957            },
958            true => err,
959        }
960
961        if self.opts.pooling_memory_protection_keys.is_some()
962            && !self.opts.pooling_allocator.unwrap_or(false)
963        {
964            anyhow::bail!("memory protection keys require the pooling allocator");
965        }
966
967        if self.opts.pooling_max_memory_protection_keys.is_some()
968            && !self.opts.pooling_memory_protection_keys.is_some()
969        {
970            anyhow::bail!(
971                "max memory protection keys requires memory protection keys to be enabled"
972            );
973        }
974
975        match_feature! {
976            ["async" : self.wasm.async_stack_zeroing]
977            enable => config.async_stack_zeroing(enable),
978            _ => err,
979        }
980
981        if let Some(max) = self.wasm.max_wasm_stack {
982            config.max_wasm_stack(max);
983
984            // If `-Wasync-stack-size` isn't passed then automatically adjust it
985            // to the wasm stack size provided here too. That prevents the need
986            // to pass both when one can generally be inferred from the other.
987            #[cfg(any(feature = "async", feature = "stack-switching"))]
988            if self.wasm.async_stack_size.is_none() {
989                const DEFAULT_HOST_STACK: usize = 512 << 10;
990                config.async_stack_size(max + DEFAULT_HOST_STACK);
991            }
992        }
993
994        if let Some(enable) = self.wasm.relaxed_simd_deterministic {
995            config.relaxed_simd_deterministic(enable);
996        }
997        match_feature! {
998            ["cranelift" : self.wasm.wmemcheck]
999            enable => config.wmemcheck(enable),
1000            true => err,
1001        }
1002
1003        if let Some(enable) = self.wasm.gc_support {
1004            config.gc_support(enable);
1005        }
1006
1007        Ok(config)
1008    }
1009
1010    pub fn enable_wasm_features(&self, config: &mut Config) -> Result<()> {
1011        let all = self.wasm.all_proposals;
1012
1013        if let Some(enable) = self.wasm.simd.or(all) {
1014            config.wasm_simd(enable);
1015        }
1016        if let Some(enable) = self.wasm.relaxed_simd.or(all) {
1017            config.wasm_relaxed_simd(enable);
1018        }
1019        if let Some(enable) = self.wasm.bulk_memory.or(all) {
1020            config.wasm_bulk_memory(enable);
1021        }
1022        if let Some(enable) = self.wasm.multi_value.or(all) {
1023            config.wasm_multi_value(enable);
1024        }
1025        if let Some(enable) = self.wasm.tail_call.or(all) {
1026            config.wasm_tail_call(enable);
1027        }
1028        if let Some(enable) = self.wasm.multi_memory.or(all) {
1029            config.wasm_multi_memory(enable);
1030        }
1031        if let Some(enable) = self.wasm.memory64.or(all) {
1032            config.wasm_memory64(enable);
1033        }
1034        if let Some(enable) = self.wasm.stack_switching {
1035            config.wasm_stack_switching(enable);
1036        }
1037        if let Some(enable) = self.wasm.custom_page_sizes.or(all) {
1038            config.wasm_custom_page_sizes(enable);
1039        }
1040        if let Some(enable) = self.wasm.wide_arithmetic.or(all) {
1041            config.wasm_wide_arithmetic(enable);
1042        }
1043        if let Some(enable) = self.wasm.extended_const.or(all) {
1044            config.wasm_extended_const(enable);
1045        }
1046
1047        macro_rules! handle_conditionally_compiled {
1048            ($(($feature:tt, $field:tt, $method:tt))*) => ($(
1049                if let Some(enable) = self.wasm.$field.or(all) {
1050                    #[cfg(feature = $feature)]
1051                    config.$method(enable);
1052                    #[cfg(not(feature = $feature))]
1053                    if enable && all.is_none() {
1054                        anyhow::bail!("support for {} was disabled at compile-time", $feature);
1055                    }
1056                }
1057            )*)
1058        }
1059
1060        handle_conditionally_compiled! {
1061            ("component-model", component_model, wasm_component_model)
1062            ("component-model-async", component_model_async, wasm_component_model_async)
1063            ("component-model-async", component_model_async_builtins, wasm_component_model_async_builtins)
1064            ("component-model-async", component_model_async_stackful, wasm_component_model_async_stackful)
1065            ("component-model-async", component_model_threading, wasm_component_model_threading)
1066            ("component-model", component_model_error_context, wasm_component_model_error_context)
1067            ("threads", threads, wasm_threads)
1068            ("gc", gc, wasm_gc)
1069            ("gc", reference_types, wasm_reference_types)
1070            ("gc", function_references, wasm_function_references)
1071            ("gc", exceptions, wasm_exceptions)
1072            ("stack-switching", stack_switching, wasm_stack_switching)
1073        }
1074
1075        if let Some(enable) = self.wasm.component_model_gc {
1076            #[cfg(all(feature = "component-model", feature = "gc"))]
1077            config.wasm_component_model_gc(enable);
1078            #[cfg(not(all(feature = "component-model", feature = "gc")))]
1079            if enable && all.is_none() {
1080                anyhow::bail!("support for `component-model-gc` was disabled at compile time")
1081            }
1082        }
1083
1084        Ok(())
1085    }
1086
1087    pub fn from_file<P: AsRef<Path>>(path: P) -> Result<Self> {
1088        let path_ref = path.as_ref();
1089        let file_contents = fs::read_to_string(path_ref)
1090            .with_context(|| format!("failed to read config file: {path_ref:?}"))?;
1091        toml::from_str::<CommonOptions>(&file_contents)
1092            .with_context(|| format!("failed to parse TOML config file {path_ref:?}"))
1093    }
1094}
1095
1096#[cfg(test)]
1097mod tests {
1098    use wasmtime::{OptLevel, RegallocAlgorithm};
1099
1100    use super::*;
1101
1102    #[test]
1103    fn from_toml() {
1104        // empty toml
1105        let empty_toml = "";
1106        let mut common_options: CommonOptions = toml::from_str(empty_toml).unwrap();
1107        common_options.config(None).unwrap();
1108
1109        // basic toml
1110        let basic_toml = r#"
1111            [optimize]
1112            [codegen]
1113            [debug]
1114            [wasm]
1115            [wasi]
1116        "#;
1117        let mut common_options: CommonOptions = toml::from_str(basic_toml).unwrap();
1118        common_options.config(None).unwrap();
1119
1120        // toml with custom deserialization to match CLI flag parsing
1121        for (opt_value, expected) in [
1122            ("0", Some(OptLevel::None)),
1123            ("1", Some(OptLevel::Speed)),
1124            ("2", Some(OptLevel::Speed)),
1125            ("\"s\"", Some(OptLevel::SpeedAndSize)),
1126            ("\"hello\"", None), // should fail
1127            ("3", None),         // should fail
1128        ] {
1129            let toml = format!(
1130                r#"
1131                    [optimize]
1132                    opt-level = {opt_value}
1133                "#,
1134            );
1135            let parsed_opt_level = toml::from_str::<CommonOptions>(&toml)
1136                .ok()
1137                .and_then(|common_options| common_options.opts.opt_level);
1138
1139            assert_eq!(
1140                parsed_opt_level, expected,
1141                "Mismatch for input '{opt_value}'. Parsed: {parsed_opt_level:?}, Expected: {expected:?}"
1142            );
1143        }
1144
1145        // Regalloc algorithm
1146        for (regalloc_value, expected) in [
1147            ("\"backtracking\"", Some(RegallocAlgorithm::Backtracking)),
1148            ("\"single-pass\"", Some(RegallocAlgorithm::SinglePass)),
1149            ("\"hello\"", None), // should fail
1150            ("3", None),         // should fail
1151            ("true", None),      // should fail
1152        ] {
1153            let toml = format!(
1154                r#"
1155                    [optimize]
1156                    regalloc-algorithm = {regalloc_value}
1157                "#,
1158            );
1159            let parsed_regalloc_algorithm = toml::from_str::<CommonOptions>(&toml)
1160                .ok()
1161                .and_then(|common_options| common_options.opts.regalloc_algorithm);
1162            assert_eq!(
1163                parsed_regalloc_algorithm, expected,
1164                "Mismatch for input '{regalloc_value}'. Parsed: {parsed_regalloc_algorithm:?}, Expected: {expected:?}"
1165            );
1166        }
1167
1168        // Strategy
1169        for (strategy_value, expected) in [
1170            ("\"cranelift\"", Some(wasmtime::Strategy::Cranelift)),
1171            ("\"winch\"", Some(wasmtime::Strategy::Winch)),
1172            ("\"hello\"", None), // should fail
1173            ("5", None),         // should fail
1174            ("true", None),      // should fail
1175        ] {
1176            let toml = format!(
1177                r#"
1178                    [codegen]
1179                    compiler = {strategy_value}
1180                "#,
1181            );
1182            let parsed_strategy = toml::from_str::<CommonOptions>(&toml)
1183                .ok()
1184                .and_then(|common_options| common_options.codegen.compiler);
1185            assert_eq!(
1186                parsed_strategy, expected,
1187                "Mismatch for input '{strategy_value}'. Parsed: {parsed_strategy:?}, Expected: {expected:?}",
1188            );
1189        }
1190
1191        // Collector
1192        for (collector_value, expected) in [
1193            (
1194                "\"drc\"",
1195                Some(wasmtime::Collector::DeferredReferenceCounting),
1196            ),
1197            ("\"null\"", Some(wasmtime::Collector::Null)),
1198            ("\"hello\"", None), // should fail
1199            ("5", None),         // should fail
1200            ("true", None),      // should fail
1201        ] {
1202            let toml = format!(
1203                r#"
1204                    [codegen]
1205                    collector = {collector_value}
1206                "#,
1207            );
1208            let parsed_collector = toml::from_str::<CommonOptions>(&toml)
1209                .ok()
1210                .and_then(|common_options| common_options.codegen.collector);
1211            assert_eq!(
1212                parsed_collector, expected,
1213                "Mismatch for input '{collector_value}'. Parsed: {parsed_collector:?}, Expected: {expected:?}",
1214            );
1215        }
1216    }
1217}
1218
1219impl Default for CommonOptions {
1220    fn default() -> CommonOptions {
1221        CommonOptions::new()
1222    }
1223}
1224
1225impl fmt::Display for CommonOptions {
1226    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1227        let CommonOptions {
1228            codegen_raw,
1229            codegen,
1230            debug_raw,
1231            debug,
1232            opts_raw,
1233            opts,
1234            wasm_raw,
1235            wasm,
1236            wasi_raw,
1237            wasi,
1238            configured,
1239            target,
1240            config,
1241        } = self;
1242        if let Some(target) = target {
1243            write!(f, "--target {target} ")?;
1244        }
1245        if let Some(config) = config {
1246            write!(f, "--config {} ", config.display())?;
1247        }
1248
1249        let codegen_flags;
1250        let opts_flags;
1251        let wasi_flags;
1252        let wasm_flags;
1253        let debug_flags;
1254
1255        if *configured {
1256            codegen_flags = codegen.to_options();
1257            debug_flags = debug.to_options();
1258            wasi_flags = wasi.to_options();
1259            wasm_flags = wasm.to_options();
1260            opts_flags = opts.to_options();
1261        } else {
1262            codegen_flags = codegen_raw
1263                .iter()
1264                .flat_map(|t| t.0.iter())
1265                .cloned()
1266                .collect();
1267            debug_flags = debug_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1268            wasi_flags = wasi_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1269            wasm_flags = wasm_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1270            opts_flags = opts_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1271        }
1272
1273        for flag in codegen_flags {
1274            write!(f, "-C{flag} ")?;
1275        }
1276        for flag in opts_flags {
1277            write!(f, "-O{flag} ")?;
1278        }
1279        for flag in wasi_flags {
1280            write!(f, "-S{flag} ")?;
1281        }
1282        for flag in wasm_flags {
1283            write!(f, "-W{flag} ")?;
1284        }
1285        for flag in debug_flags {
1286            write!(f, "-D{flag} ")?;
1287        }
1288
1289        Ok(())
1290    }
1291}
wasmtime_cli_flags/lib.rs

wasmtime_cli_flags/
lib.rs
