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bjorn3bjorn3
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Remove implicit #[no_mangle] for #[rustc_std_internal_symbol]
1 parent bc9afca commit 4bf91e1

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16 files changed

+102
-46
lines changed

16 files changed

+102
-46
lines changed

‎compiler/rustc_codegen_cranelift/src/allocator.rs‎

Lines changed: 23 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -7,13 +7,15 @@ use rustc_ast::expand::allocator::{
77
};
88
use rustc_codegen_ssa::base::allocator_kind_for_codegen;
99
use rustc_session::config::OomStrategy;
10+
use rustc_symbol_mangling::mangle_internal_symbol;
1011

1112
use crate::prelude::*;
1213

1314
/// Returns whether an allocator shim was created
1415
pub(crate) fn codegen(tcx: TyCtxt<'_>, module: &mut dyn Module) -> bool {
1516
let Some(kind) = allocator_kind_for_codegen(tcx) else { return false };
1617
codegen_inner(
18+
tcx,
1719
module,
1820
kind,
1921
tcx.alloc_error_handler_kind(()).unwrap(),
@@ -23,6 +25,7 @@ pub(crate) fn codegen(tcx: TyCtxt<'_>, module: &mut dyn Module) -> bool {
2325
}
2426

2527
fn codegen_inner(
28+
tcx: TyCtxt<'_>,
2629
module: &mut dyn Module,
2730
kind: AllocatorKind,
2831
alloc_error_handler_kind: AllocatorKind,
@@ -62,8 +65,8 @@ fn codegen_inner(
6265
crate::common::create_wrapper_function(
6366
module,
6467
sig,
65-
&global_fn_name(method.name),
66-
&default_fn_name(method.name),
68+
&mangle_internal_symbol(tcx, &global_fn_name(method.name)),
69+
&mangle_internal_symbol(tcx, &default_fn_name(method.name)),
6770
);
6871
}
6972
}
@@ -76,19 +79,32 @@ fn codegen_inner(
7679
crate::common::create_wrapper_function(
7780
module,
7881
sig,
79-
"__rust_alloc_error_handler",
80-
&alloc_error_handler_name(alloc_error_handler_kind),
82+
&mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
83+
&mangle_internal_symbol(tcx, &alloc_error_handler_name(alloc_error_handler_kind)),
8184
);
8285

83-
let data_id = module.declare_data(OomStrategy::SYMBOL, Linkage::Export, false, false).unwrap();
86+
let data_id = module
87+
.declare_data(
88+
&mangle_internal_symbol(tcx, OomStrategy::SYMBOL),
89+
Linkage::Export,
90+
false,
91+
false,
92+
)
93+
.unwrap();
8494
let mut data = DataDescription::new();
8595
data.set_align(1);
8696
let val = oom_strategy.should_panic();
8797
data.define(Box::new([val]));
8898
module.define_data(data_id, &data).unwrap();
8999

90-
let data_id =
91-
module.declare_data(NO_ALLOC_SHIM_IS_UNSTABLE, Linkage::Export, false, false).unwrap();
100+
let data_id = module
101+
.declare_data(
102+
&mangle_internal_symbol(tcx, NO_ALLOC_SHIM_IS_UNSTABLE),
103+
Linkage::Export,
104+
false,
105+
false,
106+
)
107+
.unwrap();
92108
let mut data = DataDescription::new();
93109
data.set_align(1);
94110
data.define(Box::new([0]));

‎compiler/rustc_codegen_cranelift/src/lib.rs‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -27,6 +27,7 @@ extern crate rustc_metadata;
2727
extern crate rustc_monomorphize;
2828
extern crate rustc_session;
2929
extern crate rustc_span;
30+
extern crate rustc_symbol_mangling;
3031
extern crate rustc_target;
3132

3233
// This prevents duplicating functions and statics that are already part of the host rustc process.

‎compiler/rustc_codegen_gcc/src/allocator.rs‎

Lines changed: 7 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -8,6 +8,7 @@ use rustc_ast::expand::allocator::{
88
use rustc_middle::bug;
99
use rustc_middle::ty::TyCtxt;
1010
use rustc_session::config::OomStrategy;
11+
use rustc_symbol_mangling::mangle_internal_symbol;
1112

1213
use crate::GccContext;
1314

@@ -51,8 +52,8 @@ pub(crate) unsafe fn codegen(
5152
panic!("invalid allocator output")
5253
}
5354
};
54-
let from_name = global_fn_name(method.name);
55-
let to_name = default_fn_name(method.name);
55+
let from_name = mangle_internal_symbol(tcx, &global_fn_name(method.name));
56+
let to_name = mangle_internal_symbol(tcx, &default_fn_name(method.name));
5657

5758
create_wrapper_function(tcx, context, &from_name, &to_name, &types, output);
5859
}
@@ -62,19 +63,19 @@ pub(crate) unsafe fn codegen(
6263
create_wrapper_function(
6364
tcx,
6465
context,
65-
"__rust_alloc_error_handler",
66-
alloc_error_handler_name(alloc_error_handler_kind),
66+
&mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
67+
&mangle_internal_symbol(tcx, &alloc_error_handler_name(alloc_error_handler_kind)),
6768
&[usize, usize],
6869
None,
6970
);
7071

71-
let name = OomStrategy::SYMBOL.to_string();
72+
let name = mangle_internal_symbol(tcx, OomStrategy::SYMBOL);
7273
let global = context.new_global(None, GlobalKind::Exported, i8, name);
7374
let value = tcx.sess.opts.unstable_opts.oom.should_panic();
7475
let value = context.new_rvalue_from_int(i8, value as i32);
7576
global.global_set_initializer_rvalue(value);
7677

77-
let name = NO_ALLOC_SHIM_IS_UNSTABLE.to_string();
78+
let name = mangle_internal_symbol(tcx, NO_ALLOC_SHIM_IS_UNSTABLE);
7879
let global = context.new_global(None, GlobalKind::Exported, i8, name);
7980
let value = context.new_rvalue_from_int(i8, 0);
8081
global.global_set_initializer_rvalue(value);

‎compiler/rustc_codegen_gcc/src/lib.rs‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -40,6 +40,7 @@ extern crate rustc_metadata;
4040
extern crate rustc_middle;
4141
extern crate rustc_session;
4242
extern crate rustc_span;
43+
extern crate rustc_symbol_mangling;
4344
extern crate rustc_target;
4445
#[macro_use]
4546
extern crate tracing;

‎compiler/rustc_codegen_llvm/src/allocator.rs‎

Lines changed: 7 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -7,6 +7,7 @@ use rustc_ast::expand::allocator::{
77
use rustc_middle::bug;
88
use rustc_middle::ty::TyCtxt;
99
use rustc_session::config::{DebugInfo, OomStrategy};
10+
use rustc_symbol_mangling::mangle_internal_symbol;
1011

1112
use crate::debuginfo;
1213
use crate::llvm::{self, Context, False, Module, True, Type};
@@ -54,8 +55,8 @@ pub(crate) unsafe fn codegen(
5455
}
5556
};
5657

57-
let from_name = global_fn_name(method.name);
58-
let to_name = default_fn_name(method.name);
58+
let from_name = mangle_internal_symbol(tcx, &global_fn_name(method.name));
59+
let to_name = mangle_internal_symbol(tcx, &default_fn_name(method.name));
5960

6061
create_wrapper_function(tcx, llcx, llmod, &from_name, &to_name, &args, output, false);
6162
}
@@ -66,15 +67,15 @@ pub(crate) unsafe fn codegen(
6667
tcx,
6768
llcx,
6869
llmod,
69-
"__rust_alloc_error_handler",
70-
alloc_error_handler_name(alloc_error_handler_kind),
70+
&mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
71+
&mangle_internal_symbol(tcx, alloc_error_handler_name(alloc_error_handler_kind)),
7172
&[usize, usize], // size, align
7273
None,
7374
true,
7475
);
7576

7677
// __rust_alloc_error_handler_should_panic
77-
let name = OomStrategy::SYMBOL;
78+
let name = mangle_internal_symbol(tcx, OomStrategy::SYMBOL);
7879
let ll_g = llvm::LLVMRustGetOrInsertGlobal(llmod, name.as_ptr().cast(), name.len(), i8);
7980
if tcx.sess.default_hidden_visibility() {
8081
llvm::LLVMRustSetVisibility(ll_g, llvm::Visibility::Hidden);
@@ -83,7 +84,7 @@ pub(crate) unsafe fn codegen(
8384
let llval = llvm::LLVMConstInt(i8, val as u64, False);
8485
llvm::LLVMSetInitializer(ll_g, llval);
8586

86-
let name = NO_ALLOC_SHIM_IS_UNSTABLE;
87+
let name = mangle_internal_symbol(tcx, NO_ALLOC_SHIM_IS_UNSTABLE);
8788
let ll_g = llvm::LLVMRustGetOrInsertGlobal(llmod, name.as_ptr().cast(), name.len(), i8);
8889
if tcx.sess.default_hidden_visibility() {
8990
llvm::LLVMRustSetVisibility(ll_g, llvm::Visibility::Hidden);

‎compiler/rustc_codegen_llvm/src/intrinsic.rs‎

Lines changed: 5 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -19,6 +19,7 @@ use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, LayoutOf};
1919
use rustc_middle::ty::{self, GenericArgsRef, Ty};
2020
use rustc_middle::{bug, span_bug};
2121
use rustc_span::{sym, Span, Symbol};
22+
use rustc_symbol_mangling::mangle_internal_symbol;
2223
use rustc_target::abi::{self, Align, Float, HasDataLayout, Primitive, Size};
2324
use rustc_target::spec::{HasTargetSpec, PanicStrategy};
2425
use tracing::debug;
@@ -737,7 +738,10 @@ fn codegen_msvc_try<'ll>(
737738
let type_name = bx.const_bytes(b"rust_panic\0");
738739
let type_info =
739740
bx.const_struct(&[type_info_vtable, bx.const_null(bx.type_ptr()), type_name], false);
740-
let tydesc = bx.declare_global("__rust_panic_type_info", bx.val_ty(type_info));
741+
let tydesc = bx.declare_global(
742+
&mangle_internal_symbol(bx.tcx, "__rust_panic_type_info"),
743+
bx.val_ty(type_info),
744+
);
741745
unsafe {
742746
llvm::LLVMRustSetLinkage(tydesc, llvm::Linkage::LinkOnceODRLinkage);
743747
llvm::SetUniqueComdat(bx.llmod, tydesc);

‎compiler/rustc_codegen_ssa/src/back/symbol_export.rs‎

Lines changed: 11 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -2,7 +2,7 @@ use crate::base::allocator_kind_for_codegen;
22

33
use std::collections::hash_map::Entry::*;
44

5-
use rustc_ast::expand::allocator::{ALLOCATOR_METHODS, NO_ALLOC_SHIM_IS_UNSTABLE};
5+
use rustc_ast::expand::allocator::{global_fn_name, ALLOCATOR_METHODS, NO_ALLOC_SHIM_IS_UNSTABLE};
66
use rustc_data_structures::unord::UnordMap;
77
use rustc_hir::def::DefKind;
88
use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, LocalDefId, LOCAL_CRATE};
@@ -17,6 +17,7 @@ use rustc_middle::ty::{self, SymbolName, TyCtxt};
1717
use rustc_middle::ty::{GenericArgKind, GenericArgsRef};
1818
use rustc_middle::util::Providers;
1919
use rustc_session::config::{CrateType, OomStrategy};
20+
use rustc_symbol_mangling::mangle_internal_symbol;
2021
use rustc_target::spec::{SanitizerSet, TlsModel};
2122
use tracing::debug;
2223

@@ -220,8 +221,11 @@ fn exported_symbols_provider_local(
220221
if allocator_kind_for_codegen(tcx).is_some() {
221222
for symbol_name in ALLOCATOR_METHODS
222223
.iter()
223-
.map(|method| format!("__rust_{}", method.name))
224-
.chain(["__rust_alloc_error_handler".to_string(), OomStrategy::SYMBOL.to_string()])
224+
.map(|method| mangle_internal_symbol(tcx, global_fn_name(method.name).as_str()))
225+
.chain([
226+
mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
227+
mangle_internal_symbol(tcx, OomStrategy::SYMBOL),
228+
])
225229
{
226230
let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, &symbol_name));
227231

@@ -235,8 +239,10 @@ fn exported_symbols_provider_local(
235239
));
236240
}
237241

238-
let exported_symbol =
239-
ExportedSymbol::NoDefId(SymbolName::new(tcx, NO_ALLOC_SHIM_IS_UNSTABLE));
242+
let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(
243+
tcx,
244+
&mangle_internal_symbol(tcx, NO_ALLOC_SHIM_IS_UNSTABLE),
245+
));
240246
symbols.push((
241247
exported_symbol,
242248
SymbolExportInfo {

‎compiler/rustc_codegen_ssa/src/base.rs‎

Lines changed: 21 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -38,6 +38,7 @@ use rustc_session::config::{self, CrateType, EntryFnType, OptLevel, OutputType};
3838
use rustc_session::Session;
3939
use rustc_span::symbol::sym;
4040
use rustc_span::{Symbol, DUMMY_SP};
41+
use rustc_symbol_mangling::mangle_internal_symbol;
4142
use rustc_target::abi::FIRST_VARIANT;
4243

4344
use std::cmp;
@@ -926,7 +927,19 @@ impl CrateInfo {
926927
.for_each(|(_, linked_symbols)| {
927928
let mut symbols = missing_weak_lang_items
928929
.iter()
929-
.map(|item| (format!("{prefix}{item}"), SymbolExportKind::Text))
930+
.map(|item| {
931+
(
932+
format!(
933+
"{prefix}{}",
934+
if *item == sym::rust_eh_personality {
935+
"rust_eh_personality".to_owned()
936+
} else {
937+
mangle_internal_symbol(tcx, item.as_str())
938+
}
939+
),
940+
SymbolExportKind::Text,
941+
)
942+
})
930943
.collect::<Vec<_>>();
931944
symbols.sort_unstable_by(|a, b| a.0.cmp(&b.0));
932945
linked_symbols.extend(symbols);
@@ -939,7 +952,13 @@ impl CrateInfo {
939952
// errors.
940953
linked_symbols.extend(ALLOCATOR_METHODS.iter().map(|method| {
941954
(
942-
format!("{prefix}{}", global_fn_name(method.name).as_str()),
955+
format!(
956+
"{prefix}{}",
957+
mangle_internal_symbol(
958+
tcx,
959+
global_fn_name(method.name).as_str()
960+
)
961+
),
943962
SymbolExportKind::Text,
944963
)
945964
}));

‎compiler/rustc_codegen_ssa/src/codegen_attrs.rs‎

Lines changed: 11 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -652,25 +652,23 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs {
652652
// strippable by the linker.
653653
//
654654
// Additionally weak lang items have predetermined symbol names.
655-
if WEAK_LANG_ITEMS.iter().any(|&l| tcx.lang_items().get(l) == Some(did.to_def_id())) {
656-
codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
657-
}
658655
if let Some((name, _)) = lang_items::extract(attrs)
659656
&& let Some(lang_item) = LangItem::from_name(name)
660-
&& let Some(link_name) = lang_item.link_name()
661657
{
662-
codegen_fn_attrs.export_name = Some(link_name);
663-
codegen_fn_attrs.link_name = Some(link_name);
658+
if WEAK_LANG_ITEMS.iter().any(|&l| l == lang_item) {
659+
codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
660+
}
661+
if lang_item == LangItem::EhPersonality {
662+
// rust_eh_personality must not be mangled as LLVM hard-codes the name.
663+
codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
664+
}
665+
if let Some(link_name) = lang_item.link_name() {
666+
codegen_fn_attrs.export_name = Some(link_name);
667+
codegen_fn_attrs.link_name = Some(link_name);
668+
}
664669
}
665670
check_link_name_xor_ordinal(tcx, &codegen_fn_attrs, link_ordinal_span);
666671

667-
// Internal symbols to the standard library all have no_mangle semantics in
668-
// that they have defined symbol names present in the function name. This
669-
// also applies to weak symbols where they all have known symbol names.
670-
if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL) {
671-
codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
672-
}
673-
674672
// Any linkage to LLVM intrinsics for now forcibly marks them all as never
675673
// unwinds since LLVM sometimes can't handle codegen which `invoke`s
676674
// intrinsic functions.

‎compiler/rustc_symbol_mangling/src/v0.rs‎

Lines changed: 9 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -76,6 +76,15 @@ pub(super) fn mangle<'tcx>(
7676
}
7777

7878
pub fn mangle_internal_symbol<'tcx>(tcx: TyCtxt<'tcx>, item_name: &str) -> String {
79+
if item_name == "rust_eh_personality" {
80+
// LLVM depends on the rust_eh_personality symbol to not be renamed
81+
return "rust_eh_personality".to_owned();
82+
} else if item_name == "__rust_no_alloc_shim_is_unstable" {
83+
// Temporary back compat hack to give people the chance to migrate to
84+
// include #[rustc_std_internal_symbol].
85+
return "__rust_no_alloc_shim_is_unstable".to_owned();
86+
}
87+
7988
let prefix = "_R";
8089
let mut cx: SymbolMangler<'_> = SymbolMangler {
8190
tcx,

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