Module rustc_ap_rustc_target::spec[][src]

Expand description

Flexible target specification.

Rust targets a wide variety of usecases, and in the interest of flexibility, allows new target triples to be defined in configuration files. Most users will not need to care about these, but this is invaluable when porting Rust to a new platform, and allows for an unprecedented level of control over how the compiler works.

Using custom targets

A target triple, as passed via rustc --target=TRIPLE, will first be compared against the list of built-in targets. This is to ease distributing rustc (no need for configuration files) and also to hold these built-in targets as immutable and sacred. If TRIPLE is not one of the built-in targets, rustc will check if a file named TRIPLE exists. If it does, it will be loaded as the target configuration. If the file does not exist, rustc will search each directory in the environment variable RUST_TARGET_PATH for a file named TRIPLE.json. The first one found will be loaded. If no file is found in any of those directories, a fatal error will be given.

Projects defining their own targets should use --target=path/to/my-awesome-platform.json instead of adding to RUST_TARGET_PATH.

Defining a new target

Targets are defined using JSON. The Target struct in this module defines the format the JSON file should take, though each underscore in the field names should be replaced with a hyphen (-) in the JSON file. Some fields are required in every target specification, such as llvm-target, target-endian, target-pointer-width, data-layout, arch, and os. In general, options passed to rustc with -C override the target’s settings, though target-feature and link-args will add to the list specified by the target, rather than replace.

Modules

abi
crt_objects

Object files providing support for basic runtime facilities and added to the produced binaries at the start and at the end of linking.

Structs

SanitizerSet
Target

Everything rustc knows about how to compile for a specific target.

TargetOptions

Optional aspects of a target specification.

Enums

CodeModel
LinkOutputKind

Everything is flattened to a single enum to make the json encoding/decoding less annoying.

LinkerFlavor
LldFlavor
MergeFunctions
PanicStrategy
RelocModel
RelroLevel
SplitDebuginfo
StackProbeType
TargetTriple

Either a target triple string or a path to a JSON file.

TlsModel

Constants

TARGETS

List of supported targets

Traits

HasTargetSpec

Type Definitions

LinkArgs