blob: 1e6bc413118ec1baddc35f558702d3d1767da798 [file] [log] [blame]
use std::ops::ControlFlow;
use std::path::{Path, PathBuf};
use rustc_ast::CRATE_NODE_ID;
use rustc_attr as attr;
use rustc_data_structures::fx::FxHashSet;
use rustc_middle::query::LocalCrate;
use rustc_middle::ty::{List, ParamEnv, ParamEnvAnd, Ty, TyCtxt};
use rustc_session::Session;
use rustc_session::config::CrateType;
use rustc_session::cstore::{
DllCallingConvention, DllImport, ForeignModule, NativeLib, PeImportNameType,
};
use rustc_session::parse::feature_err;
use rustc_session::search_paths::PathKind;
use rustc_session::utils::NativeLibKind;
use rustc_span::def_id::{DefId, LOCAL_CRATE};
use rustc_span::symbol::{Symbol, sym};
use rustc_target::spec::LinkSelfContainedComponents;
use rustc_target::spec::abi::Abi;
use crate::{errors, fluent_generated};
pub fn walk_native_lib_search_dirs<R>(
sess: &Session,
self_contained_components: LinkSelfContainedComponents,
apple_sdk_root: Option<&Path>,
mut f: impl FnMut(&Path, bool /*is_framework*/) -> ControlFlow<R>,
) -> ControlFlow<R> {
// Library search paths explicitly supplied by user (`-L` on the command line).
for search_path in sess.target_filesearch(PathKind::Native).cli_search_paths() {
f(&search_path.dir, false)?;
}
for search_path in sess.target_filesearch(PathKind::Framework).cli_search_paths() {
// Frameworks are looked up strictly in framework-specific paths.
if search_path.kind != PathKind::All {
f(&search_path.dir, true)?;
}
}
// The toolchain ships some native library components and self-contained linking was enabled.
// Add the self-contained library directory to search paths.
if self_contained_components.intersects(
LinkSelfContainedComponents::LIBC
| LinkSelfContainedComponents::UNWIND
| LinkSelfContainedComponents::MINGW,
) {
f(&sess.target_tlib_path.dir.join("self-contained"), false)?;
}
// Toolchains for some targets may ship `libunwind.a`, but place it into the main sysroot
// library directory instead of the self-contained directories.
// Sanitizer libraries have the same issue and are also linked by name on Apple targets.
// The targets here should be in sync with `copy_third_party_objects` in bootstrap.
// FIXME: implement `-Clink-self-contained=+/-unwind,+/-sanitizers`, move the shipped libunwind
// and sanitizers to self-contained directory, and stop adding this search path.
if sess.target.vendor == "fortanix"
|| sess.target.os == "linux"
|| sess.target.os == "fuchsia"
|| sess.target.is_like_osx && !sess.opts.unstable_opts.sanitizer.is_empty()
{
f(&sess.target_tlib_path.dir, false)?;
}
// Mac Catalyst uses the macOS SDK, but to link to iOS-specific frameworks
// we must have the support library stubs in the library search path (#121430).
if let Some(sdk_root) = apple_sdk_root
&& sess.target.llvm_target.contains("macabi")
{
f(&sdk_root.join("System/iOSSupport/usr/lib"), false)?;
f(&sdk_root.join("System/iOSSupport/System/Library/Frameworks"), true)?;
}
ControlFlow::Continue(())
}
pub fn try_find_native_static_library(
sess: &Session,
name: &str,
verbatim: bool,
) -> Option<PathBuf> {
let formats = if verbatim {
vec![("".into(), "".into())]
} else {
let os = (sess.target.staticlib_prefix.clone(), sess.target.staticlib_suffix.clone());
// On Windows, static libraries sometimes show up as libfoo.a and other
// times show up as foo.lib
let unix = ("lib".into(), ".a".into());
if os == unix { vec![os] } else { vec![os, unix] }
};
// FIXME: Account for self-contained linking settings and Apple SDK.
walk_native_lib_search_dirs(
sess,
LinkSelfContainedComponents::empty(),
None,
|dir, is_framework| {
if !is_framework {
for (prefix, suffix) in &formats {
let test = dir.join(format!("{prefix}{name}{suffix}"));
if test.exists() {
return ControlFlow::Break(test);
}
}
}
ControlFlow::Continue(())
},
)
.break_value()
}
pub fn try_find_native_dynamic_library(
sess: &Session,
name: &str,
verbatim: bool,
) -> Option<PathBuf> {
let formats = if verbatim {
vec![("".into(), "".into())]
} else {
// While the official naming convention for MSVC import libraries
// is foo.lib...
let os = (sess.target.staticlib_prefix.clone(), sess.target.staticlib_suffix.clone());
// ... Meson follows the libfoo.dll.a convention to
// disambiguate .a for static libraries
let meson = ("lib".into(), ".dll.a".into());
// and MinGW uses .a altogether
let mingw = ("lib".into(), ".a".into());
vec![os, meson, mingw]
};
walk_native_lib_search_dirs(
sess,
LinkSelfContainedComponents::empty(),
None,
|dir, is_framework| {
if !is_framework {
for (prefix, suffix) in &formats {
let test = dir.join(format!("{prefix}{name}{suffix}"));
if test.exists() {
return ControlFlow::Break(test);
}
}
}
ControlFlow::Continue(())
},
)
.break_value()
}
pub fn find_native_static_library(name: &str, verbatim: bool, sess: &Session) -> PathBuf {
try_find_native_static_library(sess, name, verbatim)
.unwrap_or_else(|| sess.dcx().emit_fatal(errors::MissingNativeLibrary::new(name, verbatim)))
}
fn find_bundled_library(
name: Symbol,
verbatim: Option<bool>,
kind: NativeLibKind,
has_cfg: bool,
tcx: TyCtxt<'_>,
) -> Option<Symbol> {
let sess = tcx.sess;
if let NativeLibKind::Static { bundle: Some(true) | None, whole_archive } = kind
&& tcx.crate_types().iter().any(|t| matches!(t, &CrateType::Rlib | CrateType::Staticlib))
&& (sess.opts.unstable_opts.packed_bundled_libs || has_cfg || whole_archive == Some(true))
{
let verbatim = verbatim.unwrap_or(false);
return find_native_static_library(name.as_str(), verbatim, sess)
.file_name()
.and_then(|s| s.to_str())
.map(Symbol::intern);
}
None
}
pub(crate) fn collect(tcx: TyCtxt<'_>, LocalCrate: LocalCrate) -> Vec<NativeLib> {
let mut collector = Collector { tcx, libs: Vec::new() };
if tcx.sess.opts.unstable_opts.link_directives {
for module in tcx.foreign_modules(LOCAL_CRATE).values() {
collector.process_module(module);
}
}
collector.process_command_line();
collector.libs
}
pub(crate) fn relevant_lib(sess: &Session, lib: &NativeLib) -> bool {
match lib.cfg {
Some(ref cfg) => attr::cfg_matches(cfg, sess, CRATE_NODE_ID, None),
None => true,
}
}
struct Collector<'tcx> {
tcx: TyCtxt<'tcx>,
libs: Vec<NativeLib>,
}
impl<'tcx> Collector<'tcx> {
fn process_module(&mut self, module: &ForeignModule) {
let ForeignModule { def_id, abi, ref foreign_items } = *module;
let def_id = def_id.expect_local();
let sess = self.tcx.sess;
if matches!(abi, Abi::Rust | Abi::RustIntrinsic) {
return;
}
// Process all of the #[link(..)]-style arguments
let features = self.tcx.features();
for m in self.tcx.get_attrs(def_id, sym::link) {
let Some(items) = m.meta_item_list() else {
continue;
};
let mut name = None;
let mut kind = None;
let mut modifiers = None;
let mut cfg = None;
let mut wasm_import_module = None;
let mut import_name_type = None;
for item in items.iter() {
match item.name_or_empty() {
sym::name => {
if name.is_some() {
sess.dcx().emit_err(errors::MultipleNamesInLink { span: item.span() });
continue;
}
let Some(link_name) = item.value_str() else {
sess.dcx().emit_err(errors::LinkNameForm { span: item.span() });
continue;
};
let span = item.name_value_literal_span().unwrap();
if link_name.is_empty() {
sess.dcx().emit_err(errors::EmptyLinkName { span });
}
name = Some((link_name, span));
}
sym::kind => {
if kind.is_some() {
sess.dcx().emit_err(errors::MultipleKindsInLink { span: item.span() });
continue;
}
let Some(link_kind) = item.value_str() else {
sess.dcx().emit_err(errors::LinkKindForm { span: item.span() });
continue;
};
let span = item.name_value_literal_span().unwrap();
let link_kind = match link_kind.as_str() {
"static" => NativeLibKind::Static { bundle: None, whole_archive: None },
"dylib" => NativeLibKind::Dylib { as_needed: None },
"framework" => {
if !sess.target.is_like_osx {
sess.dcx().emit_err(errors::LinkFrameworkApple { span });
}
NativeLibKind::Framework { as_needed: None }
}
"raw-dylib" => {
if !sess.target.is_like_windows {
sess.dcx().emit_err(errors::RawDylibOnlyWindows { span });
}
NativeLibKind::RawDylib
}
"link-arg" => {
if !features.link_arg_attribute() {
feature_err(
sess,
sym::link_arg_attribute,
span,
fluent_generated::metadata_link_arg_unstable,
)
.emit();
}
NativeLibKind::LinkArg
}
kind => {
sess.dcx().emit_err(errors::UnknownLinkKind { span, kind });
continue;
}
};
kind = Some(link_kind);
}
sym::modifiers => {
if modifiers.is_some() {
sess.dcx()
.emit_err(errors::MultipleLinkModifiers { span: item.span() });
continue;
}
let Some(link_modifiers) = item.value_str() else {
sess.dcx().emit_err(errors::LinkModifiersForm { span: item.span() });
continue;
};
modifiers = Some((link_modifiers, item.name_value_literal_span().unwrap()));
}
sym::cfg => {
if cfg.is_some() {
sess.dcx().emit_err(errors::MultipleCfgs { span: item.span() });
continue;
}
let Some(link_cfg) = item.meta_item_list() else {
sess.dcx().emit_err(errors::LinkCfgForm { span: item.span() });
continue;
};
let [link_cfg] = link_cfg else {
sess.dcx()
.emit_err(errors::LinkCfgSinglePredicate { span: item.span() });
continue;
};
let Some(link_cfg) = link_cfg.meta_item_or_bool() else {
sess.dcx()
.emit_err(errors::LinkCfgSinglePredicate { span: item.span() });
continue;
};
if !features.link_cfg() {
feature_err(
sess,
sym::link_cfg,
item.span(),
fluent_generated::metadata_link_cfg_unstable,
)
.emit();
}
cfg = Some(link_cfg.clone());
}
sym::wasm_import_module => {
if wasm_import_module.is_some() {
sess.dcx().emit_err(errors::MultipleWasmImport { span: item.span() });
continue;
}
let Some(link_wasm_import_module) = item.value_str() else {
sess.dcx().emit_err(errors::WasmImportForm { span: item.span() });
continue;
};
wasm_import_module = Some((link_wasm_import_module, item.span()));
}
sym::import_name_type => {
if import_name_type.is_some() {
sess.dcx()
.emit_err(errors::MultipleImportNameType { span: item.span() });
continue;
}
let Some(link_import_name_type) = item.value_str() else {
sess.dcx().emit_err(errors::ImportNameTypeForm { span: item.span() });
continue;
};
if self.tcx.sess.target.arch != "x86" {
sess.dcx().emit_err(errors::ImportNameTypeX86 { span: item.span() });
continue;
}
let link_import_name_type = match link_import_name_type.as_str() {
"decorated" => PeImportNameType::Decorated,
"noprefix" => PeImportNameType::NoPrefix,
"undecorated" => PeImportNameType::Undecorated,
import_name_type => {
sess.dcx().emit_err(errors::UnknownImportNameType {
span: item.span(),
import_name_type,
});
continue;
}
};
import_name_type = Some((link_import_name_type, item.span()));
}
_ => {
sess.dcx().emit_err(errors::UnexpectedLinkArg { span: item.span() });
}
}
}
// Do this outside the above loop so we don't depend on modifiers coming after kinds
let mut verbatim = None;
if let Some((modifiers, span)) = modifiers {
for modifier in modifiers.as_str().split(',') {
let (modifier, value) = match modifier.strip_prefix(&['+', '-']) {
Some(m) => (m, modifier.starts_with('+')),
None => {
sess.dcx().emit_err(errors::InvalidLinkModifier { span });
continue;
}
};
macro report_unstable_modifier($feature: ident) {
if !features.$feature() {
// FIXME: make this translatable
#[expect(rustc::untranslatable_diagnostic)]
feature_err(
sess,
sym::$feature,
span,
format!("linking modifier `{modifier}` is unstable"),
)
.emit();
}
}
let assign_modifier = |dst: &mut Option<bool>| {
if dst.is_some() {
sess.dcx().emit_err(errors::MultipleModifiers { span, modifier });
} else {
*dst = Some(value);
}
};
match (modifier, &mut kind) {
("bundle", Some(NativeLibKind::Static { bundle, .. })) => {
assign_modifier(bundle)
}
("bundle", _) => {
sess.dcx().emit_err(errors::BundleNeedsStatic { span });
}
("verbatim", _) => assign_modifier(&mut verbatim),
("whole-archive", Some(NativeLibKind::Static { whole_archive, .. })) => {
assign_modifier(whole_archive)
}
("whole-archive", _) => {
sess.dcx().emit_err(errors::WholeArchiveNeedsStatic { span });
}
("as-needed", Some(NativeLibKind::Dylib { as_needed }))
| ("as-needed", Some(NativeLibKind::Framework { as_needed })) => {
report_unstable_modifier!(native_link_modifiers_as_needed);
assign_modifier(as_needed)
}
("as-needed", _) => {
sess.dcx().emit_err(errors::AsNeededCompatibility { span });
}
_ => {
sess.dcx().emit_err(errors::UnknownLinkModifier { span, modifier });
}
}
}
}
if let Some((_, span)) = wasm_import_module {
if name.is_some() || kind.is_some() || modifiers.is_some() || cfg.is_some() {
sess.dcx().emit_err(errors::IncompatibleWasmLink { span });
}
}
if wasm_import_module.is_some() {
(name, kind) = (wasm_import_module, Some(NativeLibKind::WasmImportModule));
}
let Some((name, name_span)) = name else {
sess.dcx().emit_err(errors::LinkRequiresName { span: m.span });
continue;
};
// Do this outside of the loop so that `import_name_type` can be specified before `kind`.
if let Some((_, span)) = import_name_type {
if kind != Some(NativeLibKind::RawDylib) {
sess.dcx().emit_err(errors::ImportNameTypeRaw { span });
}
}
let dll_imports = match kind {
Some(NativeLibKind::RawDylib) => {
if name.as_str().contains('\0') {
sess.dcx().emit_err(errors::RawDylibNoNul { span: name_span });
}
foreign_items
.iter()
.map(|&child_item| {
self.build_dll_import(
abi,
import_name_type.map(|(import_name_type, _)| import_name_type),
child_item,
)
})
.collect()
}
_ => {
for &child_item in foreign_items {
if self.tcx.def_kind(child_item).has_codegen_attrs()
&& self.tcx.codegen_fn_attrs(child_item).link_ordinal.is_some()
{
let link_ordinal_attr =
self.tcx.get_attr(child_item, sym::link_ordinal).unwrap();
sess.dcx().emit_err(errors::LinkOrdinalRawDylib {
span: link_ordinal_attr.span,
});
}
}
Vec::new()
}
};
let kind = kind.unwrap_or(NativeLibKind::Unspecified);
let filename = find_bundled_library(name, verbatim, kind, cfg.is_some(), self.tcx);
self.libs.push(NativeLib {
name,
filename,
kind,
cfg,
foreign_module: Some(def_id.to_def_id()),
verbatim,
dll_imports,
});
}
}
// Process libs passed on the command line
fn process_command_line(&mut self) {
// First, check for errors
let mut renames = FxHashSet::default();
for lib in &self.tcx.sess.opts.libs {
if let NativeLibKind::Framework { .. } = lib.kind
&& !self.tcx.sess.target.is_like_osx
{
// Cannot check this when parsing options because the target is not yet available.
self.tcx.dcx().emit_err(errors::LibFrameworkApple);
}
if let Some(ref new_name) = lib.new_name {
let any_duplicate = self.libs.iter().any(|n| n.name.as_str() == lib.name);
if new_name.is_empty() {
self.tcx.dcx().emit_err(errors::EmptyRenamingTarget { lib_name: &lib.name });
} else if !any_duplicate {
self.tcx.dcx().emit_err(errors::RenamingNoLink { lib_name: &lib.name });
} else if !renames.insert(&lib.name) {
self.tcx.dcx().emit_err(errors::MultipleRenamings { lib_name: &lib.name });
}
}
}
// Update kind and, optionally, the name of all native libraries
// (there may be more than one) with the specified name. If any
// library is mentioned more than once, keep the latest mention
// of it, so that any possible dependent libraries appear before
// it. (This ensures that the linker is able to see symbols from
// all possible dependent libraries before linking in the library
// in question.)
for passed_lib in &self.tcx.sess.opts.libs {
// If we've already added any native libraries with the same
// name, they will be pulled out into `existing`, so that we
// can move them to the end of the list below.
let mut existing = self
.libs
.extract_if(|lib| {
if lib.name.as_str() == passed_lib.name {
// FIXME: This whole logic is questionable, whether modifiers are
// involved or not, library reordering and kind overriding without
// explicit `:rename` in particular.
if lib.has_modifiers() || passed_lib.has_modifiers() {
match lib.foreign_module {
Some(def_id) => {
self.tcx.dcx().emit_err(errors::NoLinkModOverride {
span: Some(self.tcx.def_span(def_id)),
})
}
None => self
.tcx
.dcx()
.emit_err(errors::NoLinkModOverride { span: None }),
};
}
if passed_lib.kind != NativeLibKind::Unspecified {
lib.kind = passed_lib.kind;
}
if let Some(new_name) = &passed_lib.new_name {
lib.name = Symbol::intern(new_name);
}
lib.verbatim = passed_lib.verbatim;
return true;
}
false
})
.collect::<Vec<_>>();
if existing.is_empty() {
// Add if not found
let new_name: Option<&str> = passed_lib.new_name.as_deref();
let name = Symbol::intern(new_name.unwrap_or(&passed_lib.name));
let filename = find_bundled_library(
name,
passed_lib.verbatim,
passed_lib.kind,
false,
self.tcx,
);
self.libs.push(NativeLib {
name,
filename,
kind: passed_lib.kind,
cfg: None,
foreign_module: None,
verbatim: passed_lib.verbatim,
dll_imports: Vec::new(),
});
} else {
// Move all existing libraries with the same name to the
// end of the command line.
self.libs.append(&mut existing);
}
}
}
fn i686_arg_list_size(&self, item: DefId) -> usize {
let argument_types: &List<Ty<'_>> = self.tcx.instantiate_bound_regions_with_erased(
self.tcx
.type_of(item)
.instantiate_identity()
.fn_sig(self.tcx)
.inputs()
.map_bound(|slice| self.tcx.mk_type_list(slice)),
);
argument_types
.iter()
.map(|ty| {
let layout = self
.tcx
.layout_of(ParamEnvAnd { param_env: ParamEnv::empty(), value: ty })
.expect("layout")
.layout;
// In both stdcall and fastcall, we always round up the argument size to the
// nearest multiple of 4 bytes.
(layout.size().bytes_usize() + 3) & !3
})
.sum()
}
fn build_dll_import(
&self,
abi: Abi,
import_name_type: Option<PeImportNameType>,
item: DefId,
) -> DllImport {
let span = self.tcx.def_span(item);
// this logic is similar to `Target::adjust_abi` (in rustc_target/src/spec/mod.rs) but errors on unsupported inputs
let calling_convention = if self.tcx.sess.target.arch == "x86" {
match abi {
Abi::C { .. } | Abi::Cdecl { .. } => DllCallingConvention::C,
Abi::Stdcall { .. } => DllCallingConvention::Stdcall(self.i686_arg_list_size(item)),
// On Windows, `extern "system"` behaves like msvc's `__stdcall`.
// `__stdcall` only applies on x86 and on non-variadic functions:
// https://learn.microsoft.com/en-us/cpp/cpp/stdcall?view=msvc-170
Abi::System { .. } => {
let c_variadic =
self.tcx.type_of(item).instantiate_identity().fn_sig(self.tcx).c_variadic();
if c_variadic {
DllCallingConvention::C
} else {
DllCallingConvention::Stdcall(self.i686_arg_list_size(item))
}
}
Abi::Fastcall { .. } => {
DllCallingConvention::Fastcall(self.i686_arg_list_size(item))
}
Abi::Vectorcall { .. } => {
DllCallingConvention::Vectorcall(self.i686_arg_list_size(item))
}
_ => {
self.tcx.dcx().emit_fatal(errors::UnsupportedAbiI686 { span });
}
}
} else {
match abi {
Abi::C { .. } | Abi::Win64 { .. } | Abi::System { .. } => DllCallingConvention::C,
_ => {
self.tcx.dcx().emit_fatal(errors::UnsupportedAbi { span });
}
}
};
let codegen_fn_attrs = self.tcx.codegen_fn_attrs(item);
let import_name_type = codegen_fn_attrs
.link_ordinal
.map_or(import_name_type, |ord| Some(PeImportNameType::Ordinal(ord)));
DllImport {
name: codegen_fn_attrs.link_name.unwrap_or(self.tcx.item_name(item)),
import_name_type,
calling_convention,
span,
is_fn: self.tcx.def_kind(item).is_fn_like(),
}
}
}