Revert "Auto merge of #118568 - DianQK:no-builtins-symbols, r=pnkfelix"

This reverts commit 503e129328, reversing
changes made to 0e7f91b75e.

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -60,7 +60,7 @@ fn prepare_lto(
     };
 
     let symbol_filter = &|&(ref name, info): &(String, SymbolExportInfo)| {
-        if info.level.is_below_threshold(export_threshold) || info.used || info.used_compiler {
+        if info.level.is_below_threshold(export_threshold) || info.used {
             Some(CString::new(name.as_str()).unwrap())
         } else {
             None

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -105,21 +105,20 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, _: LocalCrate) -> DefIdMap<S
             }
         })
         .map(|def_id| {
-            let codegen_attrs = tcx.codegen_fn_attrs(def_id.to_def_id());
             // We won't link right if this symbol is stripped during LTO.
             let name = tcx.symbol_name(Instance::mono(tcx, def_id.to_def_id())).name;
             // We have to preserve the symbols of the built-in functions during LTO.
             let is_builtin_fn = is_compiler_builtins
                 && symbol_export_level(tcx, def_id.to_def_id())
-                    .is_below_threshold(SymbolExportLevel::C)
-                && codegen_attrs.flags.contains(CodegenFnAttrFlags::NO_MANGLE);
-            let used = name == "rust_eh_personality";
+                    .is_below_threshold(SymbolExportLevel::C);
+            let used = is_builtin_fn || name == "rust_eh_personality";
 
             let export_level = if special_runtime_crate {
                 SymbolExportLevel::Rust
             } else {
                 symbol_export_level(tcx, def_id.to_def_id())
             };
+            let codegen_attrs = tcx.codegen_fn_attrs(def_id.to_def_id());
             debug!(
                 "EXPORTED SYMBOL (local): {} ({:?})",
                 tcx.symbol_name(Instance::mono(tcx, def_id.to_def_id())),
@@ -139,7 +138,6 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, _: LocalCrate) -> DefIdMap<S
                 used: codegen_attrs.flags.contains(CodegenFnAttrFlags::USED)
                     || codegen_attrs.flags.contains(CodegenFnAttrFlags::USED_LINKER)
                     || used,
-                used_compiler: is_builtin_fn,
             };
             (def_id.to_def_id(), info)
         })
@@ -152,7 +150,6 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, _: LocalCrate) -> DefIdMap<S
                 level: SymbolExportLevel::C,
                 kind: SymbolExportKind::Data,
                 used: false,
-                used_compiler: false,
             },
         );
     }
@@ -201,7 +198,6 @@ fn exported_symbols_provider_local(
                         level: info.level,
                         kind: SymbolExportKind::Text,
                         used: info.used,
-                        used_compiler: false,
                     },
                 )
             })
@@ -218,7 +214,6 @@ fn exported_symbols_provider_local(
                 level: SymbolExportLevel::C,
                 kind: SymbolExportKind::Text,
                 used: false,
-                used_compiler: false,
             },
         ));
     }
@@ -238,7 +233,6 @@ fn exported_symbols_provider_local(
                     level: SymbolExportLevel::Rust,
                     kind: SymbolExportKind::Text,
                     used: false,
-                    used_compiler: false,
                 },
             ));
         }
@@ -251,7 +245,6 @@ fn exported_symbols_provider_local(
                 level: SymbolExportLevel::Rust,
                 kind: SymbolExportKind::Data,
                 used: false,
-                used_compiler: false,
             },
         ))
     }
@@ -271,7 +264,6 @@ fn exported_symbols_provider_local(
                     level: SymbolExportLevel::C,
                     kind: SymbolExportKind::Data,
                     used: false,
-                    used_compiler: false,
                 },
             )
         }));
@@ -297,7 +289,6 @@ fn exported_symbols_provider_local(
                     level: SymbolExportLevel::C,
                     kind: SymbolExportKind::Data,
                     used: false,
-                    used_compiler: false,
                 },
             )
         }));
@@ -315,7 +306,6 @@ fn exported_symbols_provider_local(
                 level: SymbolExportLevel::C,
                 kind: SymbolExportKind::Data,
                 used: true,
-                used_compiler: false,
             },
         ));
     }
@@ -356,7 +346,6 @@ fn exported_symbols_provider_local(
                                 level: SymbolExportLevel::Rust,
                                 kind: SymbolExportKind::Text,
                                 used: false,
-                                used_compiler: false,
                             },
                         ));
                     }
@@ -373,7 +362,6 @@ fn exported_symbols_provider_local(
                             level: SymbolExportLevel::Rust,
                             kind: SymbolExportKind::Text,
                             used: false,
-                            used_compiler: false,
                         },
                     ));
                 }

compiler/rustc_middle/src/middle/exported_symbols.rs

@@ -35,12 +35,7 @@ pub enum SymbolExportKind {
 pub struct SymbolExportInfo {
     pub level: SymbolExportLevel,
     pub kind: SymbolExportKind,
-    /// Used to mark these symbols not to be internalized by LTO. These symbols
-    /// are also added to `symbols.o` to avoid circular dependencies when linking.
     pub used: bool,
-    /// Also used to mark these symbols not to be internalized by LTO. But will
-    /// not be added to `symbols.o`. Currently there are only builtin functions.
-    pub used_compiler: bool,
 }
 
 #[derive(Eq, PartialEq, Debug, Copy, Clone, TyEncodable, TyDecodable, HashStable)]

src/tools/miri/src/bin/miri.rs

@@ -165,7 +165,6 @@ impl rustc_driver::Callbacks for MiriBeRustCompilerCalls {
                                     level: SymbolExportLevel::C,
                                     kind: SymbolExportKind::Text,
                                     used: false,
-                                    used_compiler: false,
                                 },
                             ))
                         }),

tests/run-make/no-builtins-symbols/Makefile

@@ -1,7 +0,0 @@
-include ../tools.mk
-
-# only-x86_64-unknown-linux-gnu
-
-all:
-	$(RUSTC) main.rs -o $(TMPDIR)/main
-	[ "$$("$(LLVM_BIN_DIR)"/llvm-nm -U $(TMPDIR)/main | grep -c __fixunssfti)" -eq "0" ]

tests/run-make/no-builtins-symbols/main.rs

@@ -1 +0,0 @@
-fn main() {}