Diagnose use of incompatible sanitizers

Emit an error when incompatible sanitizer are configured through command
line options. Previously the last one configured prevailed and others
were silently ignored.

Additionally use a set to represent configured sanitizers, making it
possible to enable multiple sanitizers at once. At least in principle,
since currently all of them are considered to be incompatible with
others.

Cargo.lock

@@ -4278,6 +4278,7 @@ dependencies = [
 name = "rustc_session"
 version = "0.0.0"
 dependencies = [
+ "bitflags",
  "getopts",
  "log",
  "num_cpus",

src/doc/unstable-book/src/compiler-flags/sanitizer.md

@@ -12,8 +12,7 @@ This feature allows for use of one of following sanitizers:
 * [ThreadSanitizer][clang-tsan] a fast data race detector.
 
 To enable a sanitizer compile with `-Zsanitizer=address`, `-Zsanitizer=leak`,
-`-Zsanitizer=memory` or `-Zsanitizer=thread`. Only a single sanitizer can be
-enabled at a time.
+`-Zsanitizer=memory` or `-Zsanitizer=thread`.
 
 # AddressSanitizer
 

src/librustc_codegen_llvm/attributes.rs

@@ -11,7 +11,7 @@ use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::ty::layout::HasTyCtxt;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_session::config::{OptLevel, Sanitizer};
+use rustc_session::config::{OptLevel, SanitizerSet};
 use rustc_session::Session;
 
 use crate::attributes;
@@ -45,26 +45,16 @@ fn inline(cx: &CodegenCx<'ll, '_>, val: &'ll Value, inline: InlineAttr) {
 
 /// Apply LLVM sanitize attributes.
 #[inline]
-pub fn sanitize(cx: &CodegenCx<'ll, '_>, codegen_fn_flags: CodegenFnAttrFlags, llfn: &'ll Value) {
-    if let Some(ref sanitizer) = cx.tcx.sess.opts.debugging_opts.sanitizer {
-        match *sanitizer {
-            Sanitizer::Address => {
-                if !codegen_fn_flags.contains(CodegenFnAttrFlags::NO_SANITIZE_ADDRESS) {
-                    llvm::Attribute::SanitizeAddress.apply_llfn(Function, llfn);
-                }
-            }
-            Sanitizer::Memory => {
-                if !codegen_fn_flags.contains(CodegenFnAttrFlags::NO_SANITIZE_MEMORY) {
-                    llvm::Attribute::SanitizeMemory.apply_llfn(Function, llfn);
-                }
-            }
-            Sanitizer::Thread => {
-                if !codegen_fn_flags.contains(CodegenFnAttrFlags::NO_SANITIZE_THREAD) {
-                    llvm::Attribute::SanitizeThread.apply_llfn(Function, llfn);
-                }
-            }
-            Sanitizer::Leak => {}
-        }
+pub fn sanitize(cx: &CodegenCx<'ll, '_>, no_sanitize: SanitizerSet, llfn: &'ll Value) {
+    let enabled = cx.tcx.sess.opts.debugging_opts.sanitizer - no_sanitize;
+    if enabled.contains(SanitizerSet::ADDRESS) {
+        llvm::Attribute::SanitizeAddress.apply_llfn(Function, llfn);
+    }
+    if enabled.contains(SanitizerSet::MEMORY) {
+        llvm::Attribute::SanitizeMemory.apply_llfn(Function, llfn);
+    }
+    if enabled.contains(SanitizerSet::THREAD) {
+        llvm::Attribute::SanitizeThread.apply_llfn(Function, llfn);
     }
 }
 
@@ -123,9 +113,14 @@ fn set_probestack(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value) {
     // Currently stack probes seem somewhat incompatible with the address
     // sanitizer and thread sanitizer. With asan we're already protected from
     // stack overflow anyway so we don't really need stack probes regardless.
-    match cx.sess().opts.debugging_opts.sanitizer {
-        Some(Sanitizer::Address | Sanitizer::Thread) => return,
-        _ => {}
+    if cx
+        .sess()
+        .opts
+        .debugging_opts
+        .sanitizer
+        .intersects(SanitizerSet::ADDRESS | SanitizerSet::THREAD)
+    {
+        return;
     }
 
     // probestack doesn't play nice either with `-C profile-generate`.
@@ -296,7 +291,7 @@ pub fn from_fn_attrs(cx: &CodegenCx<'ll, 'tcx>, llfn: &'ll Value, instance: ty::
     if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::ALLOCATOR) {
         Attribute::NoAlias.apply_llfn(llvm::AttributePlace::ReturnValue, llfn);
     }
-    sanitize(cx, codegen_fn_attrs.flags, llfn);
+    sanitize(cx, codegen_fn_attrs.no_sanitize, llfn);
 
     // Always annotate functions with the target-cpu they are compiled for.
     // Without this, ThinLTO won't inline Rust functions into Clang generated

src/librustc_codegen_llvm/back/write.rs

@@ -21,7 +21,7 @@ use rustc_fs_util::{link_or_copy, path_to_c_string};
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::bug;
 use rustc_middle::ty::TyCtxt;
-use rustc_session::config::{self, Lto, OutputType, Passes, Sanitizer, SwitchWithOptPath};
+use rustc_session::config::{self, Lto, OutputType, Passes, SanitizerSet, SwitchWithOptPath};
 use rustc_session::Session;
 use rustc_span::InnerSpan;
 use rustc_target::spec::{CodeModel, RelocModel};
@@ -394,12 +394,13 @@ pub(crate) unsafe fn optimize_with_new_llvm_pass_manager(
     let is_lto = opt_stage == llvm::OptStage::ThinLTO || opt_stage == llvm::OptStage::FatLTO;
     // Sanitizer instrumentation is only inserted during the pre-link optimization stage.
     let sanitizer_options = if !is_lto {
-        config.sanitizer.as_ref().map(|s| llvm::SanitizerOptions {
-            sanitize_memory: *s == Sanitizer::Memory,
-            sanitize_thread: *s == Sanitizer::Thread,
-            sanitize_address: *s == Sanitizer::Address,
-            sanitize_recover: config.sanitizer_recover.contains(s),
+        Some(llvm::SanitizerOptions {
+            sanitize_address: config.sanitizer.contains(SanitizerSet::ADDRESS),
+            sanitize_address_recover: config.sanitizer_recover.contains(SanitizerSet::ADDRESS),
+            sanitize_memory: config.sanitizer.contains(SanitizerSet::MEMORY),
+            sanitize_memory_recover: config.sanitizer_recover.contains(SanitizerSet::MEMORY),
             sanitize_memory_track_origins: config.sanitizer_memory_track_origins as c_int,
+            sanitize_thread: config.sanitizer.contains(SanitizerSet::THREAD),
         })
     } else {
         None
@@ -600,25 +601,18 @@ pub(crate) unsafe fn optimize(
 }
 
 unsafe fn add_sanitizer_passes(config: &ModuleConfig, passes: &mut Vec<&'static mut llvm::Pass>) {
-    let sanitizer = match &config.sanitizer {
-        None => return,
-        Some(s) => s,
-    };
-
-    let recover = config.sanitizer_recover.contains(sanitizer);
-    match sanitizer {
-        Sanitizer::Address => {
-            passes.push(llvm::LLVMRustCreateAddressSanitizerFunctionPass(recover));
-            passes.push(llvm::LLVMRustCreateModuleAddressSanitizerPass(recover));
-        }
-        Sanitizer::Memory => {
-            let track_origins = config.sanitizer_memory_track_origins as c_int;
-            passes.push(llvm::LLVMRustCreateMemorySanitizerPass(track_origins, recover));
-        }
-        Sanitizer::Thread => {
-            passes.push(llvm::LLVMRustCreateThreadSanitizerPass());
-        }
-        Sanitizer::Leak => {}
+    if config.sanitizer.contains(SanitizerSet::ADDRESS) {
+        let recover = config.sanitizer_recover.contains(SanitizerSet::ADDRESS);
+        passes.push(llvm::LLVMRustCreateAddressSanitizerFunctionPass(recover));
+        passes.push(llvm::LLVMRustCreateModuleAddressSanitizerPass(recover));
+    }
+    if config.sanitizer.contains(SanitizerSet::MEMORY) {
+        let track_origins = config.sanitizer_memory_track_origins as c_int;
+        let recover = config.sanitizer_recover.contains(SanitizerSet::MEMORY);
+        passes.push(llvm::LLVMRustCreateMemorySanitizerPass(track_origins, recover));
+    }
+    if config.sanitizer.contains(SanitizerSet::THREAD) {
+        passes.push(llvm::LLVMRustCreateThreadSanitizerPass());
     }
 }
 

src/librustc_codegen_llvm/base.rs

@@ -29,12 +29,12 @@ use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::{ModuleCodegen, ModuleKind};
 use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_middle::dep_graph;
-use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
+use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::middle::cstore::EncodedMetadata;
 use rustc_middle::middle::exported_symbols;
 use rustc_middle::mir::mono::{Linkage, Visibility};
 use rustc_middle::ty::TyCtxt;
-use rustc_session::config::DebugInfo;
+use rustc_session::config::{DebugInfo, SanitizerSet};
 use rustc_span::symbol::Symbol;
 
 use std::ffi::CString;
@@ -132,7 +132,7 @@ pub fn compile_codegen_unit(
             // If this codegen unit contains the main function, also create the
             // wrapper here
             if let Some(entry) = maybe_create_entry_wrapper::<Builder<'_, '_, '_>>(&cx) {
-                attributes::sanitize(&cx, CodegenFnAttrFlags::empty(), entry);
+                attributes::sanitize(&cx, SanitizerSet::empty(), entry);
             }
 
             // Run replace-all-uses-with for statics that need it

src/librustc_codegen_llvm/llvm/ffi.rs

@@ -439,11 +439,12 @@ pub enum OptStage {
 /// LLVMRustSanitizerOptions
 #[repr(C)]
 pub struct SanitizerOptions {
-    pub sanitize_memory: bool,
-    pub sanitize_thread: bool,
     pub sanitize_address: bool,
-    pub sanitize_recover: bool,
+    pub sanitize_address_recover: bool,
+    pub sanitize_memory: bool,
+    pub sanitize_memory_recover: bool,
     pub sanitize_memory_track_origins: c_int,
+    pub sanitize_thread: bool,
 }
 
 /// LLVMRelocMode

src/librustc_codegen_ssa/back/link.rs

@@ -4,7 +4,7 @@ use rustc_hir::def_id::CrateNum;
 use rustc_middle::middle::cstore::{EncodedMetadata, LibSource, NativeLib};
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_session::config::{self, CFGuard, CrateType, DebugInfo};
-use rustc_session::config::{OutputFilenames, OutputType, PrintRequest, Sanitizer};
+use rustc_session::config::{OutputFilenames, OutputType, PrintRequest, SanitizerSet};
 use rustc_session::output::{check_file_is_writeable, invalid_output_for_target, out_filename};
 use rustc_session::search_paths::PathKind;
 use rustc_session::utils::NativeLibKind;
@@ -766,23 +766,26 @@ fn link_natively<'a, B: ArchiveBuilder<'a>>(
     }
 }
 
-fn link_sanitizer_runtime(sess: &Session, crate_type: CrateType, linker: &mut dyn Linker) {
-    let sanitizer = match &sess.opts.debugging_opts.sanitizer {
-        Some(s) => s,
-        None => return,
-    };
-
+fn link_sanitizers(sess: &Session, crate_type: CrateType, linker: &mut dyn Linker) {
     if crate_type != CrateType::Executable {
         return;
     }
+    let sanitizer = sess.opts.debugging_opts.sanitizer;
+    if sanitizer.contains(SanitizerSet::ADDRESS) {
+        link_sanitizer_runtime(sess, linker, "asan");
+    }
+    if sanitizer.contains(SanitizerSet::LEAK) {
+        link_sanitizer_runtime(sess, linker, "lsan");
+    }
+    if sanitizer.contains(SanitizerSet::MEMORY) {
+        link_sanitizer_runtime(sess, linker, "msan");
+    }
+    if sanitizer.contains(SanitizerSet::THREAD) {
+        link_sanitizer_runtime(sess, linker, "tsan");
+    }
+}
 
-    let name = match sanitizer {
-        Sanitizer::Address => "asan",
-        Sanitizer::Leak => "lsan",
-        Sanitizer::Memory => "msan",
-        Sanitizer::Thread => "tsan",
-    };
-
+fn link_sanitizer_runtime(sess: &Session, linker: &mut dyn Linker, name: &str) {
     let default_sysroot = filesearch::get_or_default_sysroot();
     let default_tlib =
         filesearch::make_target_lib_path(&default_sysroot, sess.opts.target_triple.triple());
@@ -1548,9 +1551,10 @@ fn linker_with_args<'a, B: ArchiveBuilder<'a>>(
 
     // NO-OPT-OUT, OBJECT-FILES-NO, AUDIT-ORDER
     if sess.target.target.options.is_like_fuchsia && crate_type == CrateType::Executable {
-        let prefix = match sess.opts.debugging_opts.sanitizer {
-            Some(Sanitizer::Address) => "asan/",
-            _ => "",
+        let prefix = if sess.opts.debugging_opts.sanitizer.contains(SanitizerSet::ADDRESS) {
+            "asan/"
+        } else {
+            ""
         };
         cmd.arg(format!("--dynamic-linker={}ld.so.1", prefix));
     }
@@ -1574,7 +1578,7 @@ fn linker_with_args<'a, B: ArchiveBuilder<'a>>(
     }
 
     // OBJECT-FILES-YES, AUDIT-ORDER
-    link_sanitizer_runtime(sess, crate_type, cmd);
+    link_sanitizers(sess, crate_type, cmd);
 
     // OBJECT-FILES-NO, AUDIT-ORDER
     // Linker plugins should be specified early in the list of arguments

src/librustc_codegen_ssa/back/symbol_export.rs

@@ -15,7 +15,7 @@ use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef};
 use rustc_middle::ty::Instance;
 use rustc_middle::ty::{SymbolName, TyCtxt};
-use rustc_session::config::{CrateType, Sanitizer};
+use rustc_session::config::{CrateType, SanitizerSet};
 
 pub fn threshold(tcx: TyCtxt<'_>) -> SymbolExportLevel {
     crates_export_threshold(&tcx.sess.crate_types())
@@ -202,7 +202,7 @@ fn exported_symbols_provider_local(
         }));
     }
 
-    if let Some(Sanitizer::Memory) = tcx.sess.opts.debugging_opts.sanitizer {
+    if tcx.sess.opts.debugging_opts.sanitizer.contains(SanitizerSet::MEMORY) {
         // Similar to profiling, preserve weak msan symbol during LTO.
         const MSAN_WEAK_SYMBOLS: [&str; 2] = ["__msan_track_origins", "__msan_keep_going"];
 

src/librustc_codegen_ssa/back/write.rs

@@ -29,7 +29,7 @@ use rustc_middle::middle::exported_symbols::SymbolExportLevel;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::cgu_reuse_tracker::CguReuseTracker;
 use rustc_session::config::{self, CrateType, Lto, OutputFilenames, OutputType};
-use rustc_session::config::{Passes, Sanitizer, SwitchWithOptPath};
+use rustc_session::config::{Passes, SanitizerSet, SwitchWithOptPath};
 use rustc_session::Session;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{sym, Symbol};
@@ -86,8 +86,8 @@ pub struct ModuleConfig {
     pub pgo_gen: SwitchWithOptPath,
     pub pgo_use: Option<PathBuf>,
 
-    pub sanitizer: Option<Sanitizer>,
-    pub sanitizer_recover: Vec<Sanitizer>,
+    pub sanitizer: SanitizerSet,
+    pub sanitizer_recover: SanitizerSet,
     pub sanitizer_memory_track_origins: usize,
 
     // Flags indicating which outputs to produce.
@@ -189,10 +189,10 @@ impl ModuleConfig {
             ),
             pgo_use: if_regular!(sess.opts.cg.profile_use.clone(), None),
 
-            sanitizer: if_regular!(sess.opts.debugging_opts.sanitizer.clone(), None),
+            sanitizer: if_regular!(sess.opts.debugging_opts.sanitizer, SanitizerSet::empty()),
             sanitizer_recover: if_regular!(
-                sess.opts.debugging_opts.sanitizer_recover.clone(),
-                vec![]
+                sess.opts.debugging_opts.sanitizer_recover,
+                SanitizerSet::empty()
             ),
             sanitizer_memory_track_origins: if_regular!(
                 sess.opts.debugging_opts.sanitizer_memory_track_origins,

src/librustc_interface/tests.rs

@@ -6,7 +6,9 @@ use rustc_session::config::Strip;
 use rustc_session::config::{build_configuration, build_session_options, to_crate_config};
 use rustc_session::config::{rustc_optgroups, ErrorOutputType, ExternLocation, Options, Passes};
 use rustc_session::config::{CFGuard, ExternEntry, LinkerPluginLto, LtoCli, SwitchWithOptPath};
-use rustc_session::config::{Externs, OutputType, OutputTypes, Sanitizer, SymbolManglingVersion};
+use rustc_session::config::{
+    Externs, OutputType, OutputTypes, SanitizerSet, SymbolManglingVersion,
+};
 use rustc_session::lint::Level;
 use rustc_session::search_paths::SearchPath;
 use rustc_session::utils::NativeLibKind;
@@ -568,9 +570,9 @@ fn test_debugging_options_tracking_hash() {
     tracked!(relro_level, Some(RelroLevel::Full));
     tracked!(report_delayed_bugs, true);
     tracked!(run_dsymutil, false);
-    tracked!(sanitizer, Some(Sanitizer::Address));
+    tracked!(sanitizer, SanitizerSet::ADDRESS);
     tracked!(sanitizer_memory_track_origins, 2);
-    tracked!(sanitizer_recover, vec![Sanitizer::Address]);
+    tracked!(sanitizer_recover, SanitizerSet::ADDRESS);
     tracked!(saturating_float_casts, Some(true));
     tracked!(share_generics, Some(true));
     tracked!(show_span, Some(String::from("abc")));

src/librustc_middle/middle/codegen_fn_attrs.rs

@@ -1,5 +1,6 @@
 use crate::mir::mono::Linkage;
 use rustc_attr::{InlineAttr, OptimizeAttr};
+use rustc_session::config::SanitizerSet;
 use rustc_span::symbol::Symbol;
 
 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
@@ -30,6 +31,9 @@ pub struct CodegenFnAttrs {
     /// The `#[link_section = "..."]` attribute, or what executable section this
     /// should be placed in.
     pub link_section: Option<Symbol>,
+    /// The `#[no_sanitize(...)]` attribute. Indicates sanitizers for which
+    /// instrumentation should be disabled inside the annotated function.
+    pub no_sanitize: SanitizerSet,
 }
 
 bitflags! {
@@ -69,20 +73,12 @@ bitflags! {
         const FFI_RETURNS_TWICE         = 1 << 10;
         /// `#[track_caller]`: allow access to the caller location
         const TRACK_CALLER              = 1 << 11;
-        /// `#[no_sanitize(address)]`: disables address sanitizer instrumentation
-        const NO_SANITIZE_ADDRESS = 1 << 12;
-        /// `#[no_sanitize(memory)]`: disables memory sanitizer instrumentation
-        const NO_SANITIZE_MEMORY  = 1 << 13;
-        /// `#[no_sanitize(thread)]`: disables thread sanitizer instrumentation
-        const NO_SANITIZE_THREAD  = 1 << 14;
-        /// All `#[no_sanitize(...)]` attributes.
-        const NO_SANITIZE_ANY = Self::NO_SANITIZE_ADDRESS.bits | Self::NO_SANITIZE_MEMORY.bits | Self::NO_SANITIZE_THREAD.bits;
         /// #[ffi_pure]: applies clang's `pure` attribute to a foreign function
         /// declaration.
-        const FFI_PURE = 1 << 15;
+        const FFI_PURE                  = 1 << 12;
         /// #[ffi_const]: applies clang's `const` attribute to a foreign function
         /// declaration.
-        const FFI_CONST = 1 << 16;
+        const FFI_CONST                 = 1 << 13;
     }
 }
 
@@ -98,6 +94,7 @@ impl CodegenFnAttrs {
             target_features: vec![],
             linkage: None,
             link_section: None,
+            no_sanitize: SanitizerSet::empty(),
         }
     }