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RalfJungRalfJung
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ensure JSON-defined targets are consistent
1 parent c49a687 commit 1628e60

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5 files changed

+305
-187
lines changed

5 files changed

+305
-187
lines changed

‎compiler/rustc_target/src/spec/mod.rs

+301-3
Original file line numberDiff line numberDiff line change
@@ -34,6 +34,9 @@
3434
//! the target's settings, though `target-feature` and `link-args` will *add*
3535
//! to the list specified by the target, rather than replace.
3636
37+
// ignore-tidy-filelength
38+
39+
use std::assert_matches::assert_matches;
3740
use std::borrow::Cow;
3841
use std::collections::BTreeMap;
3942
use std::hash::{Hash, Hasher};
@@ -1605,13 +1608,11 @@ macro_rules! supported_targets {
16051608

16061609
#[cfg(test)]
16071610
mod tests {
1608-
mod tests_impl;
1609-
16101611
// Cannot put this into a separate file without duplication, make an exception.
16111612
$(
16121613
#[test] // `#[test]`
16131614
fn $module() {
1614-
tests_impl::test_target(crate::spec::targets::$module::target());
1615+
crate::spec::targets::$module::target().test_target()
16151616
}
16161617
)+
16171618
}
@@ -2849,6 +2850,302 @@ impl Target {
28492850
self.max_atomic_width.unwrap_or_else(|| self.pointer_width.into())
28502851
}
28512852

2853+
fn check_consistency(&self) -> Result<(), String> {
2854+
macro_rules! check {
2855+
($b:expr, $($msg:tt)*) => {
2856+
if !$b {
2857+
return Err(format!($($msg)*));
2858+
}
2859+
}
2860+
}
2861+
macro_rules! check_eq {
2862+
($left:expr, $right:expr, $($msg:tt)*) => {
2863+
if ($left) != ($right) {
2864+
return Err(format!($($msg)*));
2865+
}
2866+
}
2867+
}
2868+
macro_rules! check_ne {
2869+
($left:expr, $right:expr, $($msg:tt)*) => {
2870+
if ($left) == ($right) {
2871+
return Err(format!($($msg)*));
2872+
}
2873+
}
2874+
}
2875+
macro_rules! check_matches {
2876+
($left:expr, $right:pat, $($msg:tt)*) => {
2877+
if !matches!($left, $right) {
2878+
return Err(format!($($msg)*));
2879+
}
2880+
}
2881+
}
2882+
2883+
check_eq!(
2884+
self.is_like_osx,
2885+
self.vendor == "apple",
2886+
"`is_like_osx` must be set if and only if `vendor` is `apple`"
2887+
);
2888+
check_eq!(
2889+
self.is_like_solaris,
2890+
self.os == "solaris" || self.os == "illumos",
2891+
"`is_like_solaris` must be set if and only if `os` is `solaris` or `illumos`"
2892+
);
2893+
check_eq!(
2894+
self.is_like_windows,
2895+
self.os == "windows" || self.os == "uefi",
2896+
"`is_like_windows` must be set if and only if `os` is `windows` or `uefi`"
2897+
);
2898+
check_eq!(
2899+
self.is_like_wasm,
2900+
self.arch == "wasm32" || self.arch == "wasm64",
2901+
"`is_like_wasm` must be set if and only if `arch` is `wasm32` or `wasm64`"
2902+
);
2903+
if self.is_like_msvc {
2904+
check!(self.is_like_windows, "if `is_like_msvc` is set, `is_like_windows` must be set");
2905+
}
2906+
2907+
// Check that default linker flavor is compatible with some other key properties.
2908+
check_eq!(
2909+
self.is_like_osx,
2910+
matches!(self.linker_flavor, LinkerFlavor::Darwin(..)),
2911+
"`linker_flavor` must be `darwin` if and only if `is_like_osx` is set"
2912+
);
2913+
check_eq!(
2914+
self.is_like_msvc,
2915+
matches!(self.linker_flavor, LinkerFlavor::Msvc(..)),
2916+
"`linker_flavor` must be `mscv` if and only if `is_like_msvc` is set"
2917+
);
2918+
check_eq!(
2919+
self.is_like_wasm && self.os != "emscripten",
2920+
matches!(self.linker_flavor, LinkerFlavor::WasmLld(..)),
2921+
"`linker_flavor` must be `wasm-lld` if and only if `is_like_wasm` is set and the `os` is not `emscripten`",
2922+
);
2923+
check_eq!(
2924+
self.os == "emscripten",
2925+
matches!(self.linker_flavor, LinkerFlavor::EmCc),
2926+
"`linker_flavor` must be `em-cc` if and only if `os` is `emscripten`"
2927+
);
2928+
check_eq!(
2929+
self.arch == "bpf",
2930+
matches!(self.linker_flavor, LinkerFlavor::Bpf),
2931+
"`linker_flavor` must be `bpf` if and only if `arch` is `bpf`"
2932+
);
2933+
check_eq!(
2934+
self.arch == "nvptx64",
2935+
matches!(self.linker_flavor, LinkerFlavor::Ptx),
2936+
"`linker_flavor` must be `ptc` if and only if `arch` is `nvptx64`"
2937+
);
2938+
2939+
for args in [
2940+
&self.pre_link_args,
2941+
&self.late_link_args,
2942+
&self.late_link_args_dynamic,
2943+
&self.late_link_args_static,
2944+
&self.post_link_args,
2945+
] {
2946+
for (&flavor, flavor_args) in args {
2947+
check!(!flavor_args.is_empty(), "linker flavor args must not be empty");
2948+
// Check that flavors mentioned in link args are compatible with the default flavor.
2949+
match self.linker_flavor {
2950+
LinkerFlavor::Gnu(..) => {
2951+
check_matches!(
2952+
flavor,
2953+
LinkerFlavor::Gnu(..),
2954+
"mixing GNU and non-GNU linker flavors"
2955+
);
2956+
}
2957+
LinkerFlavor::Darwin(..) => {
2958+
check_matches!(
2959+
flavor,
2960+
LinkerFlavor::Darwin(..),
2961+
"mixing Darwin and non-Darwin linker flavors"
2962+
)
2963+
}
2964+
LinkerFlavor::WasmLld(..) => {
2965+
check_matches!(
2966+
flavor,
2967+
LinkerFlavor::WasmLld(..),
2968+
"mixing wasm and non-wasm linker flavors"
2969+
)
2970+
}
2971+
LinkerFlavor::Unix(..) => {
2972+
check_matches!(
2973+
flavor,
2974+
LinkerFlavor::Unix(..),
2975+
"mixing unix and non-unix linker flavors"
2976+
);
2977+
}
2978+
LinkerFlavor::Msvc(..) => {
2979+
check_matches!(
2980+
flavor,
2981+
LinkerFlavor::Msvc(..),
2982+
"mixing MSVC and non-MSVC linker flavors"
2983+
);
2984+
}
2985+
LinkerFlavor::EmCc
2986+
| LinkerFlavor::Bpf
2987+
| LinkerFlavor::Ptx
2988+
| LinkerFlavor::Llbc => {
2989+
check_eq!(flavor, self.linker_flavor, "mixing different linker flavors")
2990+
}
2991+
}
2992+
2993+
// Check that link args for cc and non-cc versions of flavors are consistent.
2994+
let check_noncc = |noncc_flavor| -> Result<(), String> {
2995+
if let Some(noncc_args) = args.get(&noncc_flavor) {
2996+
for arg in flavor_args {
2997+
if let Some(suffix) = arg.strip_prefix("-Wl,") {
2998+
check!(
2999+
noncc_args.iter().any(|a| a == suffix),
3000+
" link args for cc and non-cc versions of flavors are not consistent"
3001+
);
3002+
}
3003+
}
3004+
}
3005+
Ok(())
3006+
};
3007+
3008+
match self.linker_flavor {
3009+
LinkerFlavor::Gnu(Cc::Yes, lld) => check_noncc(LinkerFlavor::Gnu(Cc::No, lld))?,
3010+
LinkerFlavor::WasmLld(Cc::Yes) => check_noncc(LinkerFlavor::WasmLld(Cc::No))?,
3011+
LinkerFlavor::Unix(Cc::Yes) => check_noncc(LinkerFlavor::Unix(Cc::No))?,
3012+
_ => {}
3013+
}
3014+
}
3015+
3016+
// Check that link args for lld and non-lld versions of flavors are consistent.
3017+
for cc in [Cc::No, Cc::Yes] {
3018+
check_eq!(
3019+
args.get(&LinkerFlavor::Gnu(cc, Lld::No)),
3020+
args.get(&LinkerFlavor::Gnu(cc, Lld::Yes)),
3021+
"link args for lld and non-lld versions of flavors are not consistent",
3022+
);
3023+
check_eq!(
3024+
args.get(&LinkerFlavor::Darwin(cc, Lld::No)),
3025+
args.get(&LinkerFlavor::Darwin(cc, Lld::Yes)),
3026+
"link args for lld and non-lld versions of flavors are not consistent",
3027+
);
3028+
}
3029+
check_eq!(
3030+
args.get(&LinkerFlavor::Msvc(Lld::No)),
3031+
args.get(&LinkerFlavor::Msvc(Lld::Yes)),
3032+
"link args for lld and non-lld versions of flavors are not consistent",
3033+
);
3034+
}
3035+
3036+
if self.link_self_contained.is_disabled() {
3037+
check!(
3038+
self.pre_link_objects_self_contained.is_empty()
3039+
&& self.post_link_objects_self_contained.is_empty(),
3040+
"if `link_self_contained` is disabled, then `pre_link_objects_self_contained` and `post_link_objects_self_contained` must be empty",
3041+
);
3042+
}
3043+
3044+
// If your target really needs to deviate from the rules below,
3045+
// except it and document the reasons.
3046+
// Keep the default "unknown" vendor instead.
3047+
check_ne!(self.vendor, "", "`vendor` cannot be empty");
3048+
check_ne!(self.os, "", "`os` cannot be empty");
3049+
if !self.can_use_os_unknown() {
3050+
// Keep the default "none" for bare metal targets instead.
3051+
check_ne!(
3052+
self.os,
3053+
"unknown",
3054+
"`unknown` os can only be used on particular targets; use `none` for bare-metal targets"
3055+
);
3056+
}
3057+
3058+
// Check dynamic linking stuff
3059+
// BPF: when targeting user space vms (like rbpf), those can load dynamic libraries.
3060+
// hexagon: when targeting QuRT, that OS can load dynamic libraries.
3061+
// wasm{32,64}: dynamic linking is inherent in the definition of the VM.
3062+
if self.os == "none"
3063+
&& (self.arch != "bpf"
3064+
&& self.arch != "hexagon"
3065+
&& self.arch != "wasm32"
3066+
&& self.arch != "wasm64")
3067+
{
3068+
check!(
3069+
!self.dynamic_linking,
3070+
"dynamic linking is not supported on this OS/architecture"
3071+
);
3072+
}
3073+
if self.only_cdylib
3074+
|| self.crt_static_allows_dylibs
3075+
|| !self.late_link_args_dynamic.is_empty()
3076+
{
3077+
check!(
3078+
self.dynamic_linking,
3079+
"dynamic linking must be allowed when `only_cdylib` or `crt_static_allows_dylibs` or `late_link_args_dynamic` are set"
3080+
);
3081+
}
3082+
// Apparently PIC was slow on wasm at some point, see comments in wasm_base.rs
3083+
if self.dynamic_linking && !(self.is_like_wasm && self.os != "emscripten") {
3084+
check_eq!(
3085+
self.relocation_model,
3086+
RelocModel::Pic,
3087+
"targets that support dynamic linking must use the `pic` relocation model"
3088+
);
3089+
}
3090+
if self.position_independent_executables {
3091+
check_eq!(
3092+
self.relocation_model,
3093+
RelocModel::Pic,
3094+
"targets that support position-independent executables must use the `pic` relocation model"
3095+
);
3096+
}
3097+
// The UEFI targets do not support dynamic linking but still require PIC (#101377).
3098+
if self.relocation_model == RelocModel::Pic && self.os != "uefi" {
3099+
check!(
3100+
self.dynamic_linking || self.position_independent_executables,
3101+
"when the relocation model is `pic`, the target must support dynamic linking or use position-independent executables. \
3102+
Set the relocation model to `static` to avoid this requirement"
3103+
);
3104+
}
3105+
if self.static_position_independent_executables {
3106+
assert!(self.position_independent_executables);
3107+
}
3108+
if self.position_independent_executables {
3109+
assert!(self.executables);
3110+
}
3111+
3112+
// Check crt static stuff
3113+
if self.crt_static_default || self.crt_static_allows_dylibs {
3114+
assert!(self.crt_static_respected);
3115+
}
3116+
3117+
// Check that RISC-V targets always specify which ABI they use.
3118+
match &*self.arch {
3119+
"riscv32" => {
3120+
assert_matches!(&*self.llvm_abiname, "ilp32" | "ilp32f" | "ilp32d" | "ilp32e")
3121+
}
3122+
"riscv64" => {
3123+
// Note that the `lp64e` is still unstable as it's not (yet) part of the ELF psABI.
3124+
assert_matches!(&*self.llvm_abiname, "lp64" | "lp64f" | "lp64d" | "lp64q" | "lp64e")
3125+
}
3126+
_ => {}
3127+
}
3128+
3129+
Ok(())
3130+
}
3131+
3132+
/// Test target self-consistency and JSON encoding/decoding roundtrip.
3133+
#[cfg(test)]
3134+
fn test_target(mut self) {
3135+
let recycled_target = Target::from_json(self.to_json()).map(|(j, _)| j);
3136+
self.update_to_cli();
3137+
self.check_consistency().unwrap();
3138+
assert_eq!(recycled_target, Ok(self));
3139+
}
3140+
3141+
// Add your target to the whitelist if it has `std` library
3142+
// and you certainly want "unknown" for the OS name.
3143+
fn can_use_os_unknown(&self) -> bool {
3144+
self.llvm_target == "wasm32-unknown-unknown"
3145+
|| self.llvm_target == "wasm64-unknown-unknown"
3146+
|| (self.env == "sgx" && self.vendor == "fortanix")
3147+
}
3148+
28523149
/// Loads a target descriptor from a JSON object.
28533150
pub fn from_json(obj: Json) -> Result<(Target, TargetWarnings), String> {
28543151
// While ugly, this code must remain this way to retain
@@ -3456,6 +3753,7 @@ impl Target {
34563753
key!(supports_xray, bool);
34573754

34583755
base.update_from_cli();
3756+
base.check_consistency()?;
34593757

34603758
// Each field should have been read using `Json::remove` so any keys remaining are unused.
34613759
let remaining_keys = obj.keys();

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