1RUSTC(1) User Commands RUSTC(1)
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6 rustc - The Rust compiler
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9 rustc [OPTIONS] INPUT
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13 This program is a compiler for the Rust language, available at
14 https://www.rust-lang.org.
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18 -h, --help
19 Display the help message.
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21 --cfg SPEC
22 Configure the compilation environment.
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24 -L [KIND=]PATH
25 Add a directory to the library search path. The optional KIND
26 can be one of:
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28 dependency
29 only lookup transitive dependencies here
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31 crate only lookup local `extern crate` directives here
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33 native only lookup native libraries here
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35 framework
36 only look for OSX frameworks here
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38 all look for anything here (the default)
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40 -l [KIND=]NAME
41 Link the generated crate(s) to the specified library NAME. The
42 optional KIND can be one of static, dylib, or framework. If
43 omitted, dylib is assumed.
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45 --crate-type [bin|lib|rlib|dylib|cdylib|staticlib]
46 Comma separated list of types of crates for the compiler to
47 emit.
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49 --crate-name NAME
50 Specify the name of the crate being built.
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52 --emit [asm|llvm-bc|llvm-ir|obj|link|dep-info|mir][=PATH]
53 Configure the output that rustc will produce. Each emission may
54 also have an optional explicit output PATH specified for that
55 particular emission kind. This path takes precedence over the -o
56 option.
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58 --print [crate-name|file-names|sysroot|cfg|target-list|target-cpus|tar‐
59 get-features|relocation-models|code-models|tls-models|target-spec-json|
60 native-static-libs]
61 Comma separated list of compiler information to print on stdout.
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63 -g Equivalent to -C debuginfo=2.
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65 -O Equivalent to -C opt-level=2.
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67 -o FILENAME
68 Write output to FILENAME. Ignored if multiple --emit outputs are
69 specified which don't have an explicit path otherwise.
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71 --out-dir DIR
72 Write output to compiler‐chosen filename in DIR. Ignored if -o
73 is specified. Defaults to the current directory.
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75 --explain OPT
76 Provide a detailed explanation of an error message.
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78 --test Build a test harness.
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80 --target TARGET
81 Target triple for which the code is compiled. This option de‐
82 faults to the host’s target triple. The target triple has the
83 general format <arch><sub>-<vendor>-<sys>-<abi>, where:
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85 <arch> x86, arm, thumb, mips, etc.
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87 <sub> for example on ARM: v5, v6m, v7a, v7m, etc.
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89 <vendor>
90 pc, apple, nvidia, ibm, etc.
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92 <sys> none, linux, win32, darwin, cuda, etc.
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94 <abi> eabi, gnu, android, macho, elf, etc.
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96 -W help
97 Print 'lint' options and default settings.
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99 -W OPT, --warn OPT
100 Set lint warnings.
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102 -A OPT, --allow OPT
103 Set lint allowed.
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105 -D OPT, --deny OPT
106 Set lint denied.
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108 -F OPT, --forbid OPT
109 Set lint forbidden.
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111 -C FLAG[=VAL], --codegen FLAG[=VAL]
112 Set a codegen‐related flag to the value specified. Use -C help
113 to print available flags. See CODEGEN OPTIONS below.
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115 -V, --version
116 Print version info and exit.
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118 -v, --verbose
119 Use verbose output.
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121 --remap-path-prefix from=to
122 Remap source path prefixes in all output, including compiler di‐
123 agnostics, debug information, macro expansions, etc. The from=to
124 parameter is scanned from right to left, so from may contain
125 '=', but to may not.
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127 This is useful for normalizing build products, for example by
128 removing the current directory out of pathnames emitted into the
129 object files. The replacement is purely textual, with no consid‐
130 eration of the current system's pathname syntax. For example
131 --remap-path-prefix foo=bar will match foo/lib.rs but not
132 ./foo/lib.rs.
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134 --extern NAME=PATH
135 Specify where an external rust library is located. These should
136 match extern declarations in the crate's source code.
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138 --sysroot PATH
139 Override the system root.
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141 -Z FLAG
142 Set internal debugging options. Use -Z help to print available
143 options.
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145 --color auto|always|never
146 Configure coloring of output:
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148 auto colorize, if output goes to a tty (default);
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150 always always colorize output;
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152 never never colorize output.
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156 linker=/path/to/cc
157 Path to the linker utility to use when linking libraries, exe‐
158 cutables, and objects.
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160 link-args='-flag1 -flag2'
161 A space‐separated list of extra arguments to pass to the linker
162 when the linker is invoked.
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164 lto Perform LLVM link‐time optimizations.
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166 target-cpu=help
167 Selects a target processor. If the value is 'help', then a list
168 of available CPUs is printed.
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170 target-feature='+feature1,-feature2'
171 A comma‐separated list of features to enable or disable for the
172 target. A preceding '+' enables a feature while a preceding '-'
173 disables it. Available features can be discovered through llc
174 -mcpu=help.
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176 passes=val
177 A space‐separated list of extra LLVM passes to run. A value of
178 'list' will cause rustc to print all known passes and exit. The
179 passes specified are appended at the end of the normal pass man‐
180 ager.
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182 llvm-args='-arg1 -arg2'
183 A space‐separated list of arguments to pass through to LLVM.
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185 save-temps
186 If specified, the compiler will save more files (.bc, .o,
187 .no-opt.bc) generated throughout compilation in the output di‐
188 rectory.
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190 rpath If specified, then the rpath value for dynamic libraries will be
191 set in either dynamic library or executable outputs.
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193 no-prepopulate-passes
194 Suppresses pre‐population of the LLVM pass manager that is run
195 over the module.
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197 no-vectorize-loops
198 Suppresses running the loop vectorization LLVM pass, regardless
199 of optimization level.
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201 no-vectorize-slp
202 Suppresses running the LLVM SLP vectorization pass, regardless
203 of optimization level.
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205 soft-float
206 Generates software floating point library calls instead of hard‐
207 ware instructions.
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209 prefer-dynamic
210 Prefers dynamic linking to static linking.
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212 no-integrated-as
213 Force usage of an external assembler rather than LLVM's inte‐
214 grated one.
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216 no-redzone
217 Disable the use of the redzone.
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219 relocation-model=[pic,static,dynamic-no-pic]
220 The relocation model to use. (Default: pic)
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222 code-model=[small,kernel,medium,large]
223 Choose the code model to use.
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225 metadata=val
226 Metadata to mangle symbol names with.
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228 extra-filename=val
229 Extra data to put in each output filename.
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231 codegen-units=n
232 Divide crate into n units to optimize in parallel.
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234 remark=val
235 Print remarks for these optimization passes (space separated, or
236 "all").
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238 no-stack-check
239 Disable checks for stack exhaustion (a memory‐safety hazard!).
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241 debuginfo=val
242 Debug info emission level:
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244 0 no debug info;
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246 1 line‐tables only (for stacktraces and breakpoints);
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248 2 full debug info with variable and type information.
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250 opt-level=VAL
251 Optimize with possible levels 0–3, s (optimize for size), or z
252 (for minimal size)
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256 Some of these affect only test harness programs (generated via rustc
257 --test); others affect all programs which link to the Rust standard li‐
258 brary.
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261 RUST_TEST_THREADS
262 The test framework Rust provides executes tests in parallel.
263 This variable sets the maximum number of threads used for this
264 purpose. This setting is overridden by the --test-threads op‐
265 tion.
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268 RUST_TEST_NOCAPTURE
269 If set to a value other than "0", a synonym for the --nocapture
270 flag.
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273 RUST_MIN_STACK
274 Sets the minimum stack size for new threads.
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277 RUST_BACKTRACE
278 If set to a value different than "0", produces a backtrace in
279 the output of a program which panics.
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283 To build an executable from a source file with a main function:
284 $ rustc -o hello hello.rs
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286 To build a library from a source file:
287 $ rustc --crate-type=lib hello-lib.rs
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289 To build either with a crate (.rs) file:
290 $ rustc hello.rs
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292 To build an executable with debug info:
293 $ rustc -g -o hello hello.rs
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297 rustdoc(1)
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301 See https://github.com/rust-lang/rust/issues for issues.
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305 See https://github.com/rust-lang/rust/graphs/contributors or use `git
306 log --all --format='%cN <%cE>' | sort -u` in the rust source distribu‐
307 tion.
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311 This work is dual‐licensed under Apache 2.0 and MIT terms. See COPY‐
312 RIGHT file in the rust source distribution.
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316rustc 1.52.1 May 2021 RUSTC(1)