Auto merge of #118521 - dpaoliello:asan, r=<try>

Enable address sanitizer for MSVC targets using INFERASANLIBS linker flag

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1194,7 +1194,9 @@ fn add_sanitizer_libraries(sess: &Session, crate_type: CrateType, linker: &mut d
     let needs_runtime = !sess.target.is_like_android
         && match crate_type {
             CrateType::Executable => true,
-            CrateType::Dylib | CrateType::Cdylib | CrateType::ProcMacro => sess.target.is_like_osx,
+            CrateType::Dylib | CrateType::Cdylib | CrateType::ProcMacro => {
+                sess.target.is_like_osx || sess.target.is_like_msvc
+            }
             CrateType::Rlib | CrateType::Staticlib => false,
         };
 
@@ -1254,6 +1256,10 @@ fn link_sanitizer_runtime(sess: &Session, linker: &mut dyn Linker, name: &str) {
         let rpath = path.to_str().expect("non-utf8 component in path");
         linker.args(&["-Wl,-rpath", "-Xlinker", rpath]);
         linker.link_dylib(&filename, false, true);
+    } else if sess.target.is_like_msvc {
+        // MSVC provides the `/INFERASANLIBS` argument to automatically find the
+        // compatible ASAN library.
+        linker.arg("/INFERASANLIBS");
     } else {
         let filename = format!("librustc{channel}_rt.{name}.a");
         let path = find_sanitizer_runtime(sess, &filename).join(&filename);

compiler/rustc_session/src/session.rs

@@ -1574,7 +1574,10 @@ fn validate_commandline_args_with_session_available(sess: &Session) {
     }
 
     // Cannot enable crt-static with sanitizers on Linux
-    if sess.crt_static(None) && !sess.opts.unstable_opts.sanitizer.is_empty() {
+    if sess.crt_static(None)
+        && !sess.opts.unstable_opts.sanitizer.is_empty()
+        && !sess.target.is_like_msvc
+    {
         sess.emit_err(errors::CannotEnableCrtStaticLinux);
     }
 

compiler/rustc_target/src/spec/targets/i686_pc_windows_msvc.rs

@@ -1,9 +1,10 @@
-use crate::spec::{base, LinkerFlavor, Lld, Target};
+use crate::spec::{base, LinkerFlavor, Lld, SanitizerSet, Target};
 
 pub fn target() -> Target {
     let mut base = base::windows_msvc::opts();
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
+    base.supported_sanitizers = SanitizerSet::ADDRESS;
 
     base.add_pre_link_args(
         LinkerFlavor::Msvc(Lld::No),

compiler/rustc_target/src/spec/targets/x86_64_pc_windows_msvc.rs

@@ -1,10 +1,11 @@
-use crate::spec::{base, Target};
+use crate::spec::{base, SanitizerSet, Target};
 
 pub fn target() -> Target {
     let mut base = base::windows_msvc::opts();
     base.cpu = "x86-64".into();
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
+    base.supported_sanitizers = SanitizerSet::ADDRESS;
 
     Target {
         llvm_target: "x86_64-pc-windows-msvc".into(),

src/bootstrap/src/core/build_steps/test.rs

@@ -1939,6 +1939,30 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             }
         }
 
+        // Special setup to enable running with sanitizers enabled on MSVC.
+        if !builder.config.dry_run()
+            && matches!(suite, "run-make" | "run-make-fulldeps")
+            && target.contains("msvc")
+            && builder.config.sanitizers_enabled(target)
+        {
+            // Ingore interception failures: not all dlls in the process will have been built with
+            // address sanitizer enabled (e.g., ntdll.dll).
+            cmd.env("ASAN_WIN_CONTINUE_ON_INTERCEPTION_FAILURE", "1");
+            // Add the address sanitizer runtime to the PATH.
+            let asan_runtime_path =
+                builder.cc.borrow()[&target].path().parent().unwrap().to_path_buf();
+            let old_path = cmd
+                .get_envs()
+                .find_map(|(k, v)| (k == "PATH").then_some(v))
+                .flatten()
+                .map_or_else(|| env::var_os("PATH").unwrap_or_default(), |v| v.to_owned());
+            let new_path = env::join_paths(
+                env::split_paths(&old_path).chain(std::iter::once(asan_runtime_path)),
+            )
+            .expect("Could not add ASAN runtime path to PATH");
+            cmd.env("PATH", new_path);
+        }
+
         // Some UI tests trigger behavior in rustc where it reads $CARGO and changes behavior if it exists.
         // To make the tests work that rely on it not being set, make sure it is not set.
         cmd.env_remove("CARGO");