diff --git a/.gitmodules b/.gitmodules
index d5ae2564654..2802c8d6391 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -39,3 +39,6 @@
 [submodule "src/tools/rustfmt"]
 	path = src/tools/rustfmt
 	url = https://github.com/rust-lang-nursery/rustfmt.git
+[submodule "src/tools/miri"]
+	path = src/tools/miri
+	url = https://github.com/solson/miri.git
diff --git a/config.toml.example b/config.toml.example
index 266f4250132..a3790c8d202 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -291,6 +291,10 @@
 # When creating source tarballs whether or not to create a source tarball.
 #dist-src = false
 
+# Whether to also run the Miri tests suite when running tests.
+# As a side-effect also generates MIR for all libraries.
+#test-miri = false
+
 # =============================================================================
 # Options for specific targets
 #
diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 0baca9e58f4..fc27c5d3866 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -246,6 +246,12 @@ fn main() {
             }
         }
 
+        // When running miri tests, we need to generate MIR for all libraries
+        if env::var("TEST_MIRI").ok().map_or(false, |val| val == "true") && stage != "0" {
+            cmd.arg("-Zalways-encode-mir");
+            cmd.arg("-Zmir-emit-validate=1");
+        }
+
         // Force all crates compiled by this compiler to (a) be unstable and (b)
         // allow the `rustc_private` feature to link to other unstable crates
         // also in the sysroot.
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 7ff0154bf8b..9df7d6c6bef 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -249,11 +249,11 @@ macro_rules! describe {
                 tool::UnstableBookGen, tool::Tidy, tool::Linkchecker, tool::CargoTest,
                 tool::Compiletest, tool::RemoteTestServer, tool::RemoteTestClient,
                 tool::RustInstaller, tool::Cargo, tool::Rls, tool::Rustdoc, tool::Clippy,
-                native::Llvm, tool::Rustfmt),
+                native::Llvm, tool::Rustfmt, tool::Miri),
             Kind::Test => describe!(check::Tidy, check::Bootstrap, check::DefaultCompiletest,
                 check::HostCompiletest, check::Crate, check::CrateLibrustc, check::Rustdoc,
                 check::Linkcheck, check::Cargotest, check::Cargo, check::Rls, check::Docs,
-                check::ErrorIndex, check::Distcheck, check::Rustfmt),
+                check::ErrorIndex, check::Distcheck, check::Rustfmt, check::Miri),
             Kind::Bench => describe!(check::Crate, check::CrateLibrustc),
             Kind::Doc => describe!(doc::UnstableBook, doc::UnstableBookGen, doc::TheBook,
                 doc::Standalone, doc::Std, doc::Test, doc::Rustc, doc::ErrorIndex, doc::Nomicon,
@@ -475,6 +475,7 @@ pub fn cargo(&self,
              } else {
                  PathBuf::from("/path/to/nowhere/rustdoc/not/required")
              })
+             .env("TEST_MIRI", self.config.test_miri.to_string())
              .env("RUSTC_FLAGS", self.rustc_flags(target).join(" "));
 
         if mode != Mode::Tool {
diff --git a/src/bootstrap/check.rs b/src/bootstrap/check.rs
index 94bb89145fb..d2e0a8e9368 100644
--- a/src/bootstrap/check.rs
+++ b/src/bootstrap/check.rs
@@ -293,6 +293,50 @@ fn run(self, builder: &Builder) {
         try_run(build, &mut cargo);
     }
 }
+pub struct Miri {
+    host: Interned<String>,
+}
+
+impl Step for Miri {
+    type Output = ();
+    const ONLY_HOSTS: bool = true;
+    const DEFAULT: bool = true;
+
+    fn should_run(run: ShouldRun) -> ShouldRun {
+        let test_miri = run.builder.build.config.test_miri;
+        run.path("src/tools/miri").default_condition(test_miri)
+    }
+
+    fn make_run(run: RunConfig) {
+        run.builder.ensure(Miri {
+            host: run.target,
+        });
+    }
+
+    /// Runs `cargo test` for miri.
+    fn run(self, builder: &Builder) {
+        let build = builder.build;
+        let host = self.host;
+        let compiler = builder.compiler(1, host);
+
+        let miri = builder.ensure(tool::Miri { compiler, target: self.host });
+        let mut cargo = builder.cargo(compiler, Mode::Tool, host, "test");
+        cargo.arg("--manifest-path").arg(build.src.join("src/tools/miri/Cargo.toml"));
+
+        // Don't build tests dynamically, just a pain to work with
+        cargo.env("RUSTC_NO_PREFER_DYNAMIC", "1");
+        // miri tests need to know about the stage sysroot
+        cargo.env("MIRI_SYSROOT", builder.sysroot(compiler));
+        cargo.env("RUSTC_TEST_SUITE", builder.rustc(compiler));
+        cargo.env("RUSTC_LIB_PATH", builder.rustc_libdir(compiler));
+        cargo.env("MIRI_PATH", miri);
+
+        builder.add_rustc_lib_path(compiler, &mut cargo);
+
+        try_run(build, &mut cargo);
+    }
+}
+
 
 fn path_for_cargo(builder: &Builder, compiler: Compiler) -> OsString {
     // Configure PATH to find the right rustc. NB. we have to use PATH
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index 372e0906cc6..349482eab5f 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -111,6 +111,7 @@ pub struct Config {
     pub low_priority: bool,
     pub channel: String,
     pub quiet_tests: bool,
+    pub test_miri: bool,
     // Fallback musl-root for all targets
     pub musl_root: Option<PathBuf>,
     pub prefix: Option<PathBuf>,
@@ -269,6 +270,7 @@ struct Rust {
     debug: Option<bool>,
     dist_src: Option<bool>,
     quiet_tests: Option<bool>,
+    test_miri: Option<bool>,
 }
 
 /// TOML representation of how each build target is configured.
@@ -304,6 +306,7 @@ pub fn parse(args: &[String]) -> Config {
         config.codegen_tests = true;
         config.ignore_git = false;
         config.rust_dist_src = true;
+        config.test_miri = false;
 
         config.on_fail = flags.on_fail;
         config.stage = flags.stage;
@@ -444,6 +447,7 @@ pub fn parse(args: &[String]) -> Config {
             set(&mut config.channel, rust.channel.clone());
             set(&mut config.rust_dist_src, rust.dist_src);
             set(&mut config.quiet_tests, rust.quiet_tests);
+            set(&mut config.test_miri, rust.test_miri);
             config.rustc_default_linker = rust.default_linker.clone();
             config.rustc_default_ar = rust.default_ar.clone();
             config.musl_root = rust.musl_root.clone().map(PathBuf::from);
diff --git a/src/bootstrap/configure.py b/src/bootstrap/configure.py
index fa8b7613360..2438be89776 100755
--- a/src/bootstrap/configure.py
+++ b/src/bootstrap/configure.py
@@ -38,6 +38,7 @@ o("debug", "rust.debug", "debug mode; disables optimization unless `--enable-opt
 o("docs", "build.docs", "build standard library documentation")
 o("compiler-docs", "build.compiler-docs", "build compiler documentation")
 o("optimize-tests", "rust.optimize-tests", "build tests with optimizations")
+o("test-miri", "rust.test-miri", "run miri's test suite")
 o("debuginfo-tests", "rust.debuginfo-tests", "build tests with debugger metadata")
 o("quiet-tests", "rust.quiet-tests", "enable quieter output when running tests")
 o("ccache", "llvm.ccache", "invoke gcc/clang via ccache to reuse object files between builds")
diff --git a/src/bootstrap/mk/Makefile.in b/src/bootstrap/mk/Makefile.in
index 72be9c12e84..004f0c31024 100644
--- a/src/bootstrap/mk/Makefile.in
+++ b/src/bootstrap/mk/Makefile.in
@@ -56,6 +56,7 @@ check-aux:
 		src/tools/cargo \
 		src/tools/rls \
 		src/tools/rustfmt \
+		src/tools/miri \
 		src/test/pretty \
 		src/test/run-pass/pretty \
 		src/test/run-fail/pretty \
diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index d082012acc1..54124780485 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -479,6 +479,41 @@ fn run(self, builder: &Builder) -> PathBuf {
     }
 }
 
+
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
+pub struct Miri {
+    pub compiler: Compiler,
+    pub target: Interned<String>,
+}
+
+impl Step for Miri {
+    type Output = PathBuf;
+    const DEFAULT: bool = true;
+    const ONLY_HOSTS: bool = true;
+
+    fn should_run(run: ShouldRun) -> ShouldRun {
+        let builder = run.builder;
+        run.path("src/tools/miri").default_condition(builder.build.config.test_miri)
+    }
+
+    fn make_run(run: RunConfig) {
+        run.builder.ensure(Miri {
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.build.build),
+            target: run.target,
+        });
+    }
+
+    fn run(self, builder: &Builder) -> PathBuf {
+        builder.ensure(ToolBuild {
+            compiler: self.compiler,
+            target: self.target,
+            tool: "miri",
+            mode: Mode::Librustc,
+            path: "src/tools/miri",
+        })
+    }
+}
+
 impl<'a> Builder<'a> {
     /// Get a `Command` which is ready to run `tool` in `stage` built for
     /// `host`.
diff --git a/src/ci/docker/x86_64-gnu-aux/Dockerfile b/src/ci/docker/x86_64-gnu-aux/Dockerfile
index 35a387221c6..a453c62cc9e 100644
--- a/src/ci/docker/x86_64-gnu-aux/Dockerfile
+++ b/src/ci/docker/x86_64-gnu-aux/Dockerfile
@@ -17,5 +17,5 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
-ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu
+ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu --enable-test-miri
 ENV RUST_CHECK_TARGET check-aux
diff --git a/src/tools/miri b/src/tools/miri
new file mode 160000
index 00000000000..ce3576f7d81
--- /dev/null
+++ b/src/tools/miri
@@ -0,0 +1 @@
+Subproject commit ce3576f7d81931f77264f85a3c68077605310019
diff --git a/src/tools/tidy/src/lib.rs b/src/tools/tidy/src/lib.rs
index 56c0b21cd53..90bf7a5e0a6 100644
--- a/src/tools/tidy/src/lib.rs
+++ b/src/tools/tidy/src/lib.rs
@@ -65,6 +65,7 @@ fn filter_dirs(path: &Path) -> bool {
         "src/tools/clippy",
         "src/tools/rust-installer",
         "src/tools/rustfmt",
+        "src/tools/miri",
     ];
     skip.iter().any(|p| path.ends_with(p))
 }