diff --git a/.gitignore b/.gitignore
index 67e0dd8e795bb..d34ed114972c5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,7 +12,7 @@ __pycache__/
 .project
 .settings/
 .valgrindrc
-.vscode/
+.vscode
 .favorites.json
 /*-*-*-*/
 /*-*-*/
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index b5e3c4cda0a66..4b49bde0af303 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -1852,8 +1852,11 @@ pub fn rustc_optgroups() -> Vec<RustcOptGroup> {
 }
 
 // Convert strings provided as --cfg [cfgspec] into a crate_cfg
-pub fn parse_cfgspecs(cfgspecs: Vec<String>) -> FxHashSet<(String, Option<String>)> {
-    syntax::with_globals(move || {
+pub fn parse_cfgspecs(
+    driver_symbols: &[&str],
+    cfgspecs: Vec<String>,
+) -> FxHashSet<(String, Option<String>)> {
+    syntax::with_globals(driver_symbols, move || {
         let cfg = cfgspecs.into_iter().map(|s| {
             let sess = parse::ParseSess::new(FilePathMapping::empty());
             let filename = FileName::cfg_spec_source_code(&s);
@@ -1918,6 +1921,7 @@ pub fn get_cmd_lint_options(matches: &getopts::Matches,
 }
 
 pub fn build_session_options_and_crate_config(
+    driver_symbols: &[&str],
     matches: &getopts::Matches,
 ) -> (Options, FxHashSet<(String, Option<String>)>) {
     let color = match matches.opt_str("color").as_ref().map(|s| &s[..]) {
@@ -2296,7 +2300,7 @@ pub fn build_session_options_and_crate_config(
         })
         .collect();
 
-    let cfg = parse_cfgspecs(matches.opt_strs("cfg"));
+    let cfg = parse_cfgspecs(driver_symbols, matches.opt_strs("cfg"));
     let test = matches.opt_present("test");
 
     let is_unstable_enabled = nightly_options::is_unstable_enabled(matches);
@@ -2735,13 +2739,13 @@ mod tests {
     // When the user supplies --test we should implicitly supply --cfg test
     #[test]
     fn test_switch_implies_cfg_test() {
-        syntax::with_globals(|| {
+        syntax::with_globals(&[], || {
             let matches = &match optgroups().parse(&["--test".to_string()]) {
                 Ok(m) => m,
                 Err(f) => panic!("test_switch_implies_cfg_test: {}", f),
             };
             let registry = errors::registry::Registry::new(&[]);
-            let (sessopts, cfg) = build_session_options_and_crate_config(matches);
+            let (sessopts, cfg) = build_session_options_and_crate_config(&[], matches);
             let sess = build_session(sessopts, None, registry);
             let cfg = build_configuration(&sess, to_crate_config(cfg));
             assert!(cfg.contains(&(Symbol::intern("test"), None)));
@@ -2753,14 +2757,14 @@ mod tests {
     #[test]
     fn test_switch_implies_cfg_test_unless_cfg_test() {
         use syntax::symbol::sym;
-        syntax::with_globals(|| {
+        syntax::with_globals(&[], || {
             let matches = &match optgroups().parse(&["--test".to_string(),
                                                      "--cfg=test".to_string()]) {
                 Ok(m) => m,
                 Err(f) => panic!("test_switch_implies_cfg_test_unless_cfg_test: {}", f),
             };
             let registry = errors::registry::Registry::new(&[]);
-            let (sessopts, cfg) = build_session_options_and_crate_config(matches);
+            let (sessopts, cfg) = build_session_options_and_crate_config(&[], matches);
             let sess = build_session(sessopts, None, registry);
             let cfg = build_configuration(&sess, to_crate_config(cfg));
             let mut test_items = cfg.iter().filter(|&&(name, _)| name == sym::test);
@@ -2771,28 +2775,28 @@ mod tests {
 
     #[test]
     fn test_can_print_warnings() {
-        syntax::with_globals(|| {
+        syntax::with_globals(&[], || {
             let matches = optgroups().parse(&["-Awarnings".to_string()]).unwrap();
             let registry = errors::registry::Registry::new(&[]);
-            let (sessopts, _) = build_session_options_and_crate_config(&matches);
+            let (sessopts, _) = build_session_options_and_crate_config(&[], &matches);
             let sess = build_session(sessopts, None, registry);
             assert!(!sess.diagnostic().flags.can_emit_warnings);
         });
 
-        syntax::with_globals(|| {
+        syntax::with_globals(&[], || {
             let matches = optgroups()
                 .parse(&["-Awarnings".to_string(), "-Dwarnings".to_string()])
                 .unwrap();
             let registry = errors::registry::Registry::new(&[]);
-            let (sessopts, _) = build_session_options_and_crate_config(&matches);
+            let (sessopts, _) = build_session_options_and_crate_config(&[], &matches);
             let sess = build_session(sessopts, None, registry);
             assert!(sess.diagnostic().flags.can_emit_warnings);
         });
 
-        syntax::with_globals(|| {
+        syntax::with_globals(&[], || {
             let matches = optgroups().parse(&["-Adead_code".to_string()]).unwrap();
             let registry = errors::registry::Registry::new(&[]);
-            let (sessopts, _) = build_session_options_and_crate_config(&matches);
+            let (sessopts, _) = build_session_options_and_crate_config(&[], &matches);
             let sess = build_session(sessopts, None, registry);
             assert!(sess.diagnostic().flags.can_emit_warnings);
         });
@@ -3390,7 +3394,7 @@ mod tests {
         let matches = optgroups()
             .parse(&["--edition=2018".to_string()])
             .unwrap();
-        let (sessopts, _) = build_session_options_and_crate_config(&matches);
+        let (sessopts, _) = build_session_options_and_crate_config(&[], &matches);
         assert!(sessopts.edition == Edition::Edition2018)
     }
 }
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 02f8eee67b151..eb1f57995ee7e 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -122,6 +122,7 @@ impl Callbacks for DefaultCallbacks {}
 // The FileLoader provides a way to load files from sources other than the file system.
 pub fn run_compiler(
     args: &[String],
+    driver_symbols: &'static [&'static str],
     callbacks: &mut (dyn Callbacks + Send),
     file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
     emitter: Option<Box<dyn Write + Send>>
@@ -135,7 +136,7 @@ pub fn run_compiler(
 
     install_panic_hook();
 
-    let (sopts, cfg) = config::build_session_options_and_crate_config(&matches);
+    let (sopts, cfg) = config::build_session_options_and_crate_config(driver_symbols, &matches);
 
     let mut dummy_config = |sopts, cfg, diagnostic_output| {
         let mut config = interface::Config {
@@ -149,6 +150,7 @@ pub fn run_compiler(
             diagnostic_output,
             stderr: None,
             crate_name: None,
+            driver_symbols,
             lint_caps: Default::default(),
         };
         callbacks.config(&mut config);
@@ -222,6 +224,7 @@ pub fn run_compiler(
         diagnostic_output,
         stderr: None,
         crate_name: None,
+        driver_symbols,
         lint_caps: Default::default(),
     };
 
@@ -1176,7 +1179,7 @@ pub fn main() {
                             &format!("Argument {} is not valid Unicode: {:?}", i, arg))
             }))
             .collect::<Vec<_>>();
-        run_compiler(&args, &mut DefaultCallbacks, None, None)
+        run_compiler(&args, &[], &mut DefaultCallbacks, None, None)
     }).and_then(|result| result);
     process::exit(match result {
         Ok(_) => EXIT_SUCCESS,
diff --git a/src/librustc_interface/interface.rs b/src/librustc_interface/interface.rs
index f2a21d61aed4a..90e1eddc78614 100644
--- a/src/librustc_interface/interface.rs
+++ b/src/librustc_interface/interface.rs
@@ -76,6 +76,8 @@ pub struct Config {
     pub file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
     pub diagnostic_output: DiagnosticOutput,
 
+    pub driver_symbols: &'static [&'static str],
+
     /// Set to capture stderr output during compiler execution
     pub stderr: Option<Arc<Mutex<Vec<u8>>>>,
 
@@ -136,15 +138,16 @@ where
     let stderr = config.stderr.take();
     util::spawn_thread_pool(
         config.opts.debugging_opts.threads,
+        config.driver_symbols,
         &stderr,
         || run_compiler_in_existing_thread_pool(config, f),
     )
 }
 
-pub fn default_thread_pool<F, R>(f: F) -> R
+pub fn default_thread_pool<F, R>(driver_symbols: &[&str], f: F) -> R
 where
     F: FnOnce() -> R + Send,
     R: Send,
 {
-    util::spawn_thread_pool(None, &None, f)
+    util::spawn_thread_pool(None, driver_symbols, &None, f)
 }
diff --git a/src/librustc_interface/util.rs b/src/librustc_interface/util.rs
index d2d0d19180783..35ad0c9ad76bf 100644
--- a/src/librustc_interface/util.rs
+++ b/src/librustc_interface/util.rs
@@ -168,6 +168,7 @@ pub fn scoped_thread<F: FnOnce() -> R + Send, R: Send>(cfg: thread::Builder, f:
 #[cfg(not(parallel_compiler))]
 pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
     _threads: Option<usize>,
+    driver_symbols: &[&str],
     stderr: &Option<Arc<Mutex<Vec<u8>>>>,
     f: F,
 ) -> R {
@@ -178,7 +179,7 @@ pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
     }
 
     scoped_thread(cfg, || {
-        syntax::with_globals( || {
+        syntax::with_globals(driver_symbols, || {
             ty::tls::GCX_PTR.set(&Lock::new(0), || {
                 if let Some(stderr) = stderr {
                     io::set_panic(Some(box Sink(stderr.clone())));
@@ -192,6 +193,7 @@ pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
 #[cfg(parallel_compiler)]
 pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
     threads: Option<usize>,
+    driver_symbols: &[&str],
     stderr: &Option<Arc<Mutex<Vec<u8>>>>,
     f: F,
 ) -> R {
@@ -213,7 +215,7 @@ pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
 
     let with_pool = move |pool: &ThreadPool| pool.install(move || f());
 
-    syntax::with_globals(|| {
+    syntax::with_globals(driver_symbols, || {
         syntax::GLOBALS.with(|syntax_globals| {
             syntax_pos::GLOBALS.with(|syntax_pos_globals| {
                 // The main handler runs for each Rayon worker thread and sets up
diff --git a/src/librustc_macros/src/symbols.rs b/src/librustc_macros/src/symbols.rs
index a4c7daf088ff2..1d10aff3790c7 100644
--- a/src/librustc_macros/src/symbols.rs
+++ b/src/librustc_macros/src/symbols.rs
@@ -166,10 +166,14 @@ pub fn symbols(input: TokenStream) -> TokenStream {
         }
 
         impl Interner {
-            pub fn fresh() -> Self {
-                Interner::prefill(&[
-                    #prefill_stream
-                ])
+            /// If your driver adds more symbols, this is the first index you may use.
+            /// Do not leave holes in the indexing scheme and add all symbols to the `Interner`
+            /// created in the closure argument to `Interner::fresh`.
+            pub const FIRST_DRIVER_INDEX: u32 = #counter;
+            /// It is the driver's responsibility to not preeintern any symbols that are already
+            /// in the list given to the closure.
+            pub fn fresh(driver_symbols: &[&str]) -> Self {
+                Interner::prefill(&[#prefill_stream], driver_symbols)
             }
         }
     });
diff --git a/src/librustdoc/clean/cfg.rs b/src/librustdoc/clean/cfg.rs
index 61399e0568cb1..fdaadb71a29f2 100644
--- a/src/librustdoc/clean/cfg.rs
+++ b/src/librustdoc/clean/cfg.rs
@@ -466,7 +466,7 @@ mod test {
 
     #[test]
     fn test_cfg_not() {
-        with_globals(|| {
+        with_globals(&[], || {
             assert_eq!(!Cfg::False, Cfg::True);
             assert_eq!(!Cfg::True, Cfg::False);
             assert_eq!(!word_cfg("test"), Cfg::Not(Box::new(word_cfg("test"))));
@@ -484,7 +484,7 @@ mod test {
 
     #[test]
     fn test_cfg_and() {
-        with_globals(|| {
+        with_globals(&[], || {
             let mut x = Cfg::False;
             x &= Cfg::True;
             assert_eq!(x, Cfg::False);
@@ -536,7 +536,7 @@ mod test {
 
     #[test]
     fn test_cfg_or() {
-        with_globals(|| {
+        with_globals(&[], || {
             let mut x = Cfg::True;
             x |= Cfg::False;
             assert_eq!(x, Cfg::True);
@@ -588,7 +588,7 @@ mod test {
 
     #[test]
     fn test_parse_ok() {
-        with_globals(|| {
+        with_globals(&[], || {
             let mi = dummy_meta_item_word("all");
             assert_eq!(Cfg::parse(&mi), Ok(word_cfg("all")));
 
@@ -622,7 +622,7 @@ mod test {
 
     #[test]
     fn test_parse_err() {
-        with_globals(|| {
+        with_globals(&[], || {
             let mi = attr::mk_name_value_item(
                 DUMMY_SP,
                 Ident::from_str("foo"),
@@ -661,7 +661,7 @@ mod test {
 
     #[test]
     fn test_render_short_html() {
-        with_globals(|| {
+        with_globals(&[], || {
             assert_eq!(
                 word_cfg("unix").render_short_html(),
                 "Unix"
@@ -741,7 +741,7 @@ mod test {
 
     #[test]
     fn test_render_long_html() {
-        with_globals(|| {
+        with_globals(&[], || {
             assert_eq!(
                 word_cfg("unix").render_long_html(),
                 "This is supported on <strong>Unix</strong> only."
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 428f4f328b907..17d62faf4fb2e 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -326,7 +326,8 @@ pub fn run_core(options: RustdocOptions) -> (clean::Crate, RenderInfo, RenderOpt
 
     let config = interface::Config {
         opts: sessopts,
-        crate_cfg: config::parse_cfgspecs(cfgs),
+        crate_cfg: config::parse_cfgspecs(&[], cfgs),
+        driver_symbols: &[],
         input,
         input_path: cpath,
         output_file: None,
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 5b76f6861de79..3ccbe4d013f1d 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -94,7 +94,7 @@ pub fn main() {
     rustc_driver::set_sigpipe_handler();
     env_logger::init();
     let res = std::thread::Builder::new().stack_size(thread_stack_size).spawn(move || {
-        rustc_interface::interface::default_thread_pool(move || {
+        rustc_interface::interface::default_thread_pool(&[], move || {
             get_args().map(|args| main_args(&args)).unwrap_or(1)
         })
     }).unwrap().join().unwrap_or(rustc_driver::EXIT_FAILURE);
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index e40dbe52ffe64..00d8ee16b0f5e 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -61,7 +61,8 @@ pub fn run(options: Options) -> i32 {
 
     let config = interface::Config {
         opts: sessopts,
-        crate_cfg: config::parse_cfgspecs(options.cfgs.clone()),
+        crate_cfg: config::parse_cfgspecs(&[], options.cfgs.clone()),
+        driver_symbols: &[],
         input,
         input_path: None,
         output_file: None,
@@ -279,7 +280,8 @@ fn run_test(test: &str, cratename: &str, filename: &FileName, line: usize,
 
     let config = interface::Config {
         opts: sessopts,
-        crate_cfg: config::parse_cfgspecs(cfgs),
+        crate_cfg: config::parse_cfgspecs(&[], cfgs),
+        driver_symbols: &[],
         input,
         input_path: None,
         output_file: Some(output_file.clone()),
@@ -385,7 +387,9 @@ pub fn make_test(s: &str,
 
     // Uses libsyntax to parse the doctest and find if there's a main fn and the extern
     // crate already is included.
-    let (already_has_main, already_has_extern_crate, found_macro) = crate::syntax::with_globals(|| {
+    let (
+        already_has_main, already_has_extern_crate, found_macro,
+    ) = crate::syntax::with_globals(&[],|| {
         use crate::syntax::{parse::{self, ParseSess}, source_map::FilePathMapping};
         use errors::emitter::EmitterWriter;
         use errors::Handler;
diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index db10ab7af5a72..e48136199e782 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -82,21 +82,23 @@ pub struct Globals {
 }
 
 impl Globals {
-    fn new() -> Globals {
+    /// See documentation on `syntax_pos::Globals` for information on the slice.
+    /// It is solely forwareded to `syntax_pos::Globals::new`
+    fn new(driver_symbols: &[&str]) -> Globals {
         Globals {
             // We have no idea how many attributes their will be, so just
             // initiate the vectors with 0 bits. We'll grow them as necessary.
             used_attrs: Lock::new(GrowableBitSet::new_empty()),
             known_attrs: Lock::new(GrowableBitSet::new_empty()),
-            syntax_pos_globals: syntax_pos::Globals::new(),
+            syntax_pos_globals: syntax_pos::Globals::new(driver_symbols),
         }
     }
 }
 
-pub fn with_globals<F, R>(f: F) -> R
+pub fn with_globals<F, R>(driver_symbols: &[&str], f: F) -> R
     where F: FnOnce() -> R
 {
-    let globals = Globals::new();
+    let globals = Globals::new(driver_symbols);
     GLOBALS.set(&globals, || {
         syntax_pos::GLOBALS.set(&globals.syntax_pos_globals, f)
     })
diff --git a/src/libsyntax/mut_visit.rs b/src/libsyntax/mut_visit.rs
index f587e63e12b94..8bbd546c0f6f6 100644
--- a/src/libsyntax/mut_visit.rs
+++ b/src/libsyntax/mut_visit.rs
@@ -1343,7 +1343,7 @@ mod tests {
 
     // make sure idents get transformed everywhere
     #[test] fn ident_transformation () {
-        with_globals(|| {
+        with_globals(&[], || {
             let mut zz_visitor = ToZzIdentMutVisitor;
             let mut krate = string_to_crate(
                 "#[a] mod b {fn c (d : e, f : g) {h!(i,j,k);l;m}}".to_string());
@@ -1358,7 +1358,7 @@ mod tests {
 
     // even inside macro defs....
     #[test] fn ident_transformation_in_defs () {
-        with_globals(|| {
+        with_globals(&[], || {
             let mut zz_visitor = ToZzIdentMutVisitor;
             let mut krate = string_to_crate(
                 "macro_rules! a {(b $c:expr $(d $e:token)f+ => \
diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 47da3ee6a6c78..4424ca70d8951 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -1601,7 +1601,7 @@ mod tests {
 
     #[test]
     fn t1() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             let mut string_reader = setup(&sm,
@@ -1649,7 +1649,7 @@ mod tests {
 
     #[test]
     fn doublecolonparsing() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             check_tokenization(setup(&sm, &sh, "a b".to_string()),
@@ -1659,7 +1659,7 @@ mod tests {
 
     #[test]
     fn dcparsing_2() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             check_tokenization(setup(&sm, &sh, "a::b".to_string()),
@@ -1669,7 +1669,7 @@ mod tests {
 
     #[test]
     fn dcparsing_3() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             check_tokenization(setup(&sm, &sh, "a ::b".to_string()),
@@ -1679,7 +1679,7 @@ mod tests {
 
     #[test]
     fn dcparsing_4() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             check_tokenization(setup(&sm, &sh, "a:: b".to_string()),
@@ -1689,7 +1689,7 @@ mod tests {
 
     #[test]
     fn character_a() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             assert_eq!(setup(&sm, &sh, "'a'".to_string()).next_token().tok,
@@ -1699,7 +1699,7 @@ mod tests {
 
     #[test]
     fn character_space() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             assert_eq!(setup(&sm, &sh, "' '".to_string()).next_token().tok,
@@ -1709,7 +1709,7 @@ mod tests {
 
     #[test]
     fn character_escaped() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             assert_eq!(setup(&sm, &sh, "'\\n'".to_string()).next_token().tok,
@@ -1719,7 +1719,7 @@ mod tests {
 
     #[test]
     fn lifetime_name() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             assert_eq!(setup(&sm, &sh, "'abc".to_string()).next_token().tok,
@@ -1729,7 +1729,7 @@ mod tests {
 
     #[test]
     fn raw_string() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             assert_eq!(setup(&sm, &sh, "r###\"\"#a\\b\x00c\"\"###".to_string())
@@ -1741,7 +1741,7 @@ mod tests {
 
     #[test]
     fn literal_suffixes() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             macro_rules! test {
@@ -1787,7 +1787,7 @@ mod tests {
 
     #[test]
     fn nested_block_comments() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             let mut lexer = setup(&sm, &sh, "/* /* */ */'a'".to_string());
@@ -1802,7 +1802,7 @@ mod tests {
 
     #[test]
     fn crlf_comments() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let sh = mk_sess(sm.clone());
             let mut lexer = setup(&sm, &sh, "// test\r\n/// test\r\n".to_string());
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 0611c1d9b42a5..48d2339d5602b 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -382,7 +382,7 @@ mod tests {
 
     #[should_panic]
     #[test] fn bad_path_expr_1() {
-        with_globals(|| {
+        with_globals(&[], || {
             string_to_expr("::abc::def::return".to_string());
         })
     }
@@ -390,7 +390,7 @@ mod tests {
     // check the token-tree-ization of macros
     #[test]
     fn string_to_tts_macro () {
-        with_globals(|| {
+        with_globals(&[], || {
             use crate::symbol::sym;
 
             let tts: Vec<_> =
@@ -447,7 +447,7 @@ mod tests {
 
     #[test]
     fn string_to_tts_1() {
-        with_globals(|| {
+        with_globals(&[], || {
             let tts = string_to_stream("fn a (b : i32) { b; }".to_string());
 
             let expected = TokenStream::new(vec![
@@ -480,7 +480,7 @@ mod tests {
     }
 
     #[test] fn parse_use() {
-        with_globals(|| {
+        with_globals(&[], || {
             let use_s = "use foo::bar::baz;";
             let vitem = string_to_item(use_s.to_string()).unwrap();
             let vitem_s = item_to_string(&vitem);
@@ -494,7 +494,7 @@ mod tests {
     }
 
     #[test] fn parse_extern_crate() {
-        with_globals(|| {
+        with_globals(&[], || {
             let ex_s = "extern crate foo;";
             let vitem = string_to_item(ex_s.to_string()).unwrap();
             let vitem_s = item_to_string(&vitem);
@@ -531,7 +531,7 @@ mod tests {
     }
 
     #[test] fn span_of_self_arg_pat_idents_are_correct() {
-        with_globals(|| {
+        with_globals(&[], || {
 
             let srcs = ["impl z { fn a (&self, &myarg: i32) {} }",
                         "impl z { fn a (&mut self, &myarg: i32) {} }",
@@ -551,7 +551,7 @@ mod tests {
     }
 
     #[test] fn parse_exprs () {
-        with_globals(|| {
+        with_globals(&[], || {
             // just make sure that they parse....
             string_to_expr("3 + 4".to_string());
             string_to_expr("a::z.froob(b,&(987+3))".to_string());
@@ -559,7 +559,7 @@ mod tests {
     }
 
     #[test] fn attrs_fix_bug () {
-        with_globals(|| {
+        with_globals(&[], || {
             string_to_item("pub fn mk_file_writer(path: &Path, flags: &[FileFlag])
                    -> Result<Box<Writer>, String> {
     #[cfg(windows)]
@@ -576,7 +576,7 @@ mod tests {
     }
 
     #[test] fn crlf_doc_comments() {
-        with_globals(|| {
+        with_globals(&[], || {
             use crate::symbol::sym;
 
             let sess = ParseSess::new(FilePathMapping::empty());
@@ -613,7 +613,7 @@ mod tests {
             new_parser_from_source_str(sess, name, source).parse_expr()
         }
 
-        with_globals(|| {
+        with_globals(&[], || {
             let sess = ParseSess::new(FilePathMapping::empty());
             let expr = parse_expr_from_source_str(PathBuf::from("foo").into(),
                 "foo!( fn main() { body } )".to_string(), &sess).unwrap();
@@ -637,7 +637,7 @@ mod tests {
     // See `recurse_into_file_modules` in the parser.
     #[test]
     fn out_of_line_mod() {
-        with_globals(|| {
+        with_globals(&[], || {
             let sess = ParseSess::new(FilePathMapping::empty());
             let item = parse_item_from_source_str(
                 PathBuf::from("foo").into(),
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 86db7a673d471..238e3dcb96551 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -3151,7 +3151,7 @@ mod tests {
 
     #[test]
     fn test_fun_to_string() {
-        with_globals(|| {
+        with_globals(&[], || {
             let abba_ident = ast::Ident::from_str("abba");
 
             let decl = ast::FnDecl {
@@ -3179,7 +3179,7 @@ mod tests {
 
     #[test]
     fn test_variant_to_string() {
-        with_globals(|| {
+        with_globals(&[], || {
             let ident = ast::Ident::from_str("principal_skinner");
 
             let var = source_map::respan(syntax_pos::DUMMY_SP, ast::Variant_ {
diff --git a/src/libsyntax/test_snippet.rs b/src/libsyntax/test_snippet.rs
index 3cf6699538de0..459d47338fe22 100644
--- a/src/libsyntax/test_snippet.rs
+++ b/src/libsyntax/test_snippet.rs
@@ -39,7 +39,7 @@ impl<T: Write> Write for Shared<T> {
 }
 
 fn test_harness(file_text: &str, span_labels: Vec<SpanLabel>, expected_output: &str) {
-    with_globals(|| {
+    with_globals(&[], || {
         let output = Arc::new(Mutex::new(Vec::new()));
 
         let source_map = Lrc::new(SourceMap::new(FilePathMapping::empty()));
diff --git a/src/libsyntax/tokenstream.rs b/src/libsyntax/tokenstream.rs
index 93b5ecadd148f..fbd11a0bd63f8 100644
--- a/src/libsyntax/tokenstream.rs
+++ b/src/libsyntax/tokenstream.rs
@@ -572,7 +572,7 @@ mod tests {
 
     #[test]
     fn test_concat() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_res = string_to_ts("foo::bar::baz");
             let test_fst = string_to_ts("foo::bar");
             let test_snd = string_to_ts("::baz");
@@ -585,7 +585,7 @@ mod tests {
 
     #[test]
     fn test_to_from_bijection() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_start = string_to_ts("foo::bar(baz)");
             let test_end = test_start.trees().collect();
             assert_eq!(test_start, test_end)
@@ -594,7 +594,7 @@ mod tests {
 
     #[test]
     fn test_eq_0() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_res = string_to_ts("foo");
             let test_eqs = string_to_ts("foo");
             assert_eq!(test_res, test_eqs)
@@ -603,7 +603,7 @@ mod tests {
 
     #[test]
     fn test_eq_1() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_res = string_to_ts("::bar::baz");
             let test_eqs = string_to_ts("::bar::baz");
             assert_eq!(test_res, test_eqs)
@@ -612,7 +612,7 @@ mod tests {
 
     #[test]
     fn test_eq_3() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_res = string_to_ts("");
             let test_eqs = string_to_ts("");
             assert_eq!(test_res, test_eqs)
@@ -621,7 +621,7 @@ mod tests {
 
     #[test]
     fn test_diseq_0() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_res = string_to_ts("::bar::baz");
             let test_eqs = string_to_ts("bar::baz");
             assert_eq!(test_res == test_eqs, false)
@@ -630,7 +630,7 @@ mod tests {
 
     #[test]
     fn test_diseq_1() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test_res = string_to_ts("(bar,baz)");
             let test_eqs = string_to_ts("bar,baz");
             assert_eq!(test_res == test_eqs, false)
@@ -639,7 +639,7 @@ mod tests {
 
     #[test]
     fn test_is_empty() {
-        with_globals(|| {
+        with_globals(&[], || {
             let test0: TokenStream = Vec::<TokenTree>::new().into_iter().collect();
             let test1: TokenStream =
                 TokenTree::Token(sp(0, 1), Token::Ident(Ident::from_str("a"), false)).into();
diff --git a/src/libsyntax/util/lev_distance.rs b/src/libsyntax/util/lev_distance.rs
index 2f150d22159fa..2d7da19a5f0b7 100644
--- a/src/libsyntax/util/lev_distance.rs
+++ b/src/libsyntax/util/lev_distance.rs
@@ -102,7 +102,7 @@ fn test_lev_distance() {
 #[test]
 fn test_find_best_match_for_name() {
     use crate::with_globals;
-    with_globals(|| {
+    with_globals(&[], || {
         let input = vec![Symbol::intern("aaab"), Symbol::intern("aaabc")];
         assert_eq!(
             find_best_match_for_name(input.iter(), "aaaa", None),
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index 39859f25f97fb..df42a0614b1e3 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -55,9 +55,11 @@ pub struct Globals {
 }
 
 impl Globals {
-    pub fn new() -> Globals {
+    /// Takes a list of symbols to be preinterned additionally to the ones from
+    /// `symbol.rs`. The default rustc driver will simply pass an empty list here.
+    pub fn new(driver_symbols: &[&str]) -> Globals {
         Globals {
-            symbol_interner: Lock::new(symbol::Interner::fresh()),
+            symbol_interner: Lock::new(symbol::Interner::fresh(driver_symbols)),
             span_interner: Lock::new(span_encoding::SpanInterner::default()),
             hygiene_data: Lock::new(hygiene::HygieneData::new()),
         }
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index c2a18c9df83ba..7fed659a0e695 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -822,10 +822,10 @@ impl Decodable for Symbol {
     }
 }
 
-// The `&'static str`s in this type actually point into the arena.
-//
-// Note that normal symbols are indexed upward from 0, and gensyms are indexed
-// downward from SymbolIndex::MAX_AS_U32.
+/// The `&'static str`s in this type actually point into the arena.
+///
+/// Note that normal symbols are indexed upward from 0, and gensyms are indexed
+/// downward from SymbolIndex::MAX_AS_U32.
 #[derive(Default)]
 pub struct Interner {
     arena: DroplessArena,
@@ -835,17 +835,17 @@ pub struct Interner {
 }
 
 impl Interner {
-    fn prefill(init: &[&str]) -> Self {
+    fn prefill(init: &[&str], driver_symbols: &[&str]) -> Self {
         let mut this = Interner::default();
-        this.names.reserve(init.len());
-        this.strings.reserve(init.len());
+        this.names.reserve(init.len() + driver_symbols.len());
+        this.strings.reserve(init.len() + driver_symbols.len());
 
         // We can't allocate empty strings in the arena, so handle this here.
         assert!(keywords::Invalid.name().as_u32() == 0 && init[0].is_empty());
         this.names.insert("", keywords::Invalid.name());
         this.strings.push("");
 
-        for string in &init[1..] {
+        for string in init[1..].iter().chain(driver_symbols) {
             this.intern(string);
         }
         this
@@ -1262,7 +1262,7 @@ mod tests {
 
     #[test]
     fn without_first_quote_test() {
-        GLOBALS.set(&Globals::new(), || {
+        GLOBALS.set(&Globals::new(&[]), || {
             let i = Ident::from_str("'break");
             assert_eq!(i.without_first_quote().name, keywords::Break.name());
         });
diff --git a/src/test/run-make-fulldeps/issue-19371/foo.rs b/src/test/run-make-fulldeps/issue-19371/foo.rs
index 0cbdf40e2f908..47bd2e15b972d 100644
--- a/src/test/run-make-fulldeps/issue-19371/foo.rs
+++ b/src/test/run-make-fulldeps/issue-19371/foo.rs
@@ -49,6 +49,7 @@ fn compile(code: String, output: PathBuf, sysroot: PathBuf) {
     let config = interface::Config {
         opts,
         crate_cfg: Default::default(),
+        driver_symbols: &[],
         input,
         input_path: None,
         output_file: Some(output),
diff --git a/src/test/run-pass-fulldeps/ast_stmt_expr_attr.rs b/src/test/run-pass-fulldeps/ast_stmt_expr_attr.rs
index d32fafd215c07..6b37b21e183f7 100644
--- a/src/test/run-pass-fulldeps/ast_stmt_expr_attr.rs
+++ b/src/test/run-pass-fulldeps/ast_stmt_expr_attr.rs
@@ -105,7 +105,7 @@ fn reject_stmt_parse(es: &str) {
 }
 
 fn main() {
-    syntax::with_globals(|| run());
+    syntax::with_globals(&[], || run());
 }
 
 fn run() {
diff --git a/src/test/run-pass-fulldeps/compiler-calls.rs b/src/test/run-pass-fulldeps/compiler-calls.rs
index b4731bbaeb5ca..f8c6f60192866 100644
--- a/src/test/run-pass-fulldeps/compiler-calls.rs
+++ b/src/test/run-pass-fulldeps/compiler-calls.rs
@@ -24,7 +24,9 @@ fn main() {
     let mut count = 1;
     let args = vec!["compiler-calls".to_string(), "foo.rs".to_string()];
     rustc_driver::report_ices_to_stderr_if_any(|| {
-        rustc_driver::run_compiler(&args, &mut TestCalls { count: &mut count }, None, None).ok();
+        rustc_driver::run_compiler(
+            &args, &[], &mut TestCalls { count: &mut count }, None, None,
+        ).ok();
     }).ok();
     assert_eq!(count, 2);
 }
diff --git a/src/test/run-pass-fulldeps/mod_dir_path_canonicalized.rs b/src/test/run-pass-fulldeps/mod_dir_path_canonicalized.rs
index 22a76a3d968aa..e053b9fb7e1c0 100644
--- a/src/test/run-pass-fulldeps/mod_dir_path_canonicalized.rs
+++ b/src/test/run-pass-fulldeps/mod_dir_path_canonicalized.rs
@@ -13,7 +13,7 @@ use syntax::parse::{self, ParseSess};
 mod gravy;
 
 pub fn main() {
-    syntax::with_globals(|| parse());
+    syntax::with_globals(&[], || parse());
 
     assert_eq!(gravy::foo(), 10);
 }
diff --git a/src/test/run-pass-fulldeps/pprust-expr-roundtrip.rs b/src/test/run-pass-fulldeps/pprust-expr-roundtrip.rs
index 80e0b0102af75..b8ff891ac0dbc 100644
--- a/src/test/run-pass-fulldeps/pprust-expr-roundtrip.rs
+++ b/src/test/run-pass-fulldeps/pprust-expr-roundtrip.rs
@@ -189,7 +189,7 @@ impl MutVisitor for AddParens {
 }
 
 fn main() {
-    syntax::with_globals(|| run());
+    syntax::with_globals(&[], || run());
 }
 
 fn run() {
diff --git a/src/tools/clippy b/src/tools/clippy
index 11194e3d050f4..456e4795e15e3 160000
--- a/src/tools/clippy
+++ b/src/tools/clippy
@@ -1 +1 @@
-Subproject commit 11194e3d050f45ff002a775f451ff6222fcd5b2c
+Subproject commit 456e4795e15e3c9584a15b49586d8bfeccabe0d2
diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index 04986b59ea0f1..9df5bd9edc64d 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -264,7 +264,7 @@ fn main() {
         *slot.borrow_mut() = Some((None, String::from("https://play.rust-lang.org/")));
     });
     let (format, dst) = parse_args();
-    let result = syntax::with_globals(move || {
+    let result = syntax::with_globals(&[], move || {
         main_with_result(format, &dst)
     });
     if let Err(e) = result {
diff --git a/src/tools/miri b/src/tools/miri
index bc0c76d861a17..224b72d6f3575 160000
--- a/src/tools/miri
+++ b/src/tools/miri
@@ -1 +1 @@
-Subproject commit bc0c76d861a178911f3f506196a7404eda1e690d
+Subproject commit 224b72d6f35756b086cc4b0479fb85036c7501cc
diff --git a/src/tools/rls b/src/tools/rls
index 5b8e99bb61958..3b7ba010ee552 160000
--- a/src/tools/rls
+++ b/src/tools/rls
@@ -1 +1 @@
-Subproject commit 5b8e99bb61958ca8abcb7c5eda70521726be1065
+Subproject commit 3b7ba010ee552f9c86bb03d61cd1bcab00221855
diff --git a/src/tools/rustfmt b/src/tools/rustfmt
index 5274b49caa1a7..db2cc882b0fdf 160000
--- a/src/tools/rustfmt
+++ b/src/tools/rustfmt
@@ -1 +1 @@
-Subproject commit 5274b49caa1a7db6ac10c76bf1a3d5710ccef569
+Subproject commit db2cc882b0fdfbc99e50edcf619d40e7bbd15cc5