Auto merge of #68474 - tmandry:rollup-6gmbet6, r=tmandry

[rust.git] / src / librustc_codegen_ssa / back / symbol_export.rs

diff --git a/src/librustc_codegen_ssa/back/symbol_export.rs b/src/librustc_codegen_ssa/back/symbol_export.rs
index a406b5f103b9d2f85f73109b6bb4cb33e7625699..d680e14bbbd5b9d884d7aa4bf6df547b8bb7d6f3 100644 (file)
--- a/src/librustc_codegen_ssa/back/symbol_export.rs
+++ b/src/librustc_codegen_ssa/back/symbol_export.rs
@@ -3,11 +3,12 @@
 
 use rustc::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc::middle::exported_symbols::{metadata_symbol_name, ExportedSymbol, SymbolExportLevel};
-use rustc::session::config;
+use rustc::session::config::{self, Sanitizer};
 use rustc::ty::query::Providers;
 use rustc::ty::subst::SubstsRef;
 use rustc::ty::Instance;
 use rustc::ty::{SymbolName, TyCtxt};
+use rustc_codegen_utils::symbol_names;
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir as hir;
@@ -205,6 +206,16 @@ fn exported_symbols_provider_local(
         }));
     }
 
+    if let Some(Sanitizer::Memory) = tcx.sess.opts.debugging_opts.sanitizer {
+        // Similar to profiling, preserve weak msan symbol during LTO.
+        const MSAN_WEAK_SYMBOLS: [&str; 2] = ["__msan_track_origins", "__msan_keep_going"];
+
+        symbols.extend(MSAN_WEAK_SYMBOLS.iter().map(|sym| {
+            let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(sym));
+            (exported_symbol, SymbolExportLevel::C)
+        }));
+    }
+
     if tcx.sess.crate_types.borrow().contains(&config::CrateType::Dylib) {
         let symbol_name = metadata_symbol_name(tcx);
         let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(&symbol_name));
@@ -358,3 +369,32 @@ fn symbol_export_level(tcx: TyCtxt<'_>, sym_def_id: DefId) -> SymbolExportLevel
         SymbolExportLevel::Rust
     }
 }
+
+/// This is the symbol name of the given instance instantiated in a specific crate.
+pub fn symbol_name_for_instance_in_crate<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    symbol: ExportedSymbol<'tcx>,
+    instantiating_crate: CrateNum,
+) -> String {
+    // If this is something instantiated in the local crate then we might
+    // already have cached the name as a query result.
+    if instantiating_crate == LOCAL_CRATE {
+        return symbol.symbol_name_for_local_instance(tcx).to_string();
+    }
+
+    // This is something instantiated in an upstream crate, so we have to use
+    // the slower (because uncached) version of computing the symbol name.
+    match symbol {
+        ExportedSymbol::NonGeneric(def_id) => symbol_names::symbol_name_for_instance_in_crate(
+            tcx,
+            Instance::mono(tcx, def_id),
+            instantiating_crate,
+        ),
+        ExportedSymbol::Generic(def_id, substs) => symbol_names::symbol_name_for_instance_in_crate(
+            tcx,
+            Instance::new(def_id, substs),
+            instantiating_crate,
+        ),
+        ExportedSymbol::NoDefId(symbol_name) => symbol_name.to_string(),
+    }
+}