Add flag to enable communication

Author: pvdrz

benches/helpers/miri_helper.rs

@@ -25,7 +25,7 @@ impl rustc_driver::Callbacks for MiriCompilerCalls<'_> {
             );
 
             self.bencher.iter(|| {
-                let config = miri::MiriConfig { validate: true, args: vec![], seed: None };
+                let config = miri::MiriConfig { validate: true, communicate: false, args: vec![], seed: None };
                 eval_main(tcx, entry_def_id, config);
             });
         });

src/bin/miri-rustc-tests.rs

@@ -48,7 +48,7 @@ impl rustc_driver::Callbacks for MiriCompilerCalls {
                     fn visit_item(&mut self, i: &'hir hir::Item) {
                         if let hir::ItemKind::Fn(.., body_id) = i.node {
                             if i.attrs.iter().any(|attr| attr.check_name(syntax::symbol::sym::test)) {
-                                let config = MiriConfig { validate: true, args: vec![], seed: None };
+                                let config = MiriConfig { validate: true, communicate: false, args: vec![], seed: None };
                                 let did = self.0.hir().body_owner_def_id(body_id);
                                 println!("running test: {}", self.0.def_path_debug_str(did));
                                 miri::eval_main(self.0, did, config);
@@ -61,7 +61,8 @@ impl rustc_driver::Callbacks for MiriCompilerCalls {
                 }
                 tcx.hir().krate().visit_all_item_likes(&mut Visitor(tcx));
             } else if let Some((entry_def_id, _)) = tcx.entry_fn(LOCAL_CRATE) {
-                let config = MiriConfig { validate: true, args: vec![], seed: None };
+
+                let config = MiriConfig { validate: true, communicate: false, args: vec![], seed: None };
                 miri::eval_main(tcx, entry_def_id, config);
 
                 compiler.session().abort_if_errors();

src/bin/miri.rs

@@ -130,6 +130,7 @@ fn main() {
 
     // Parse our arguments and split them across `rustc` and `miri`.
     let mut validate = true;
+    let mut communicate = false;
     let mut seed: Option<u64> = None;
     let mut rustc_args = vec![];
     let mut miri_args = vec![];
@@ -147,6 +148,9 @@ fn main() {
                 "-Zmiri-disable-validation" => {
                     validate = false;
                 },
+                "-Zmiri-enable-communication" => {
+                    communicate = true;
+                },
                 "--" => {
                     after_dashdash = true;
                 }
@@ -196,7 +200,7 @@ fn main() {
 
     debug!("rustc arguments: {:?}", rustc_args);
     debug!("miri arguments: {:?}", miri_args);
-    let miri_config = miri::MiriConfig { validate, args: miri_args, seed };
+    let miri_config = miri::MiriConfig { validate, communicate, args: miri_args, seed };
     let result = rustc_driver::report_ices_to_stderr_if_any(move || {
         rustc_driver::run_compiler(&rustc_args, &mut MiriCompilerCalls { miri_config }, None, None)
     }).and_then(|result| result);

src/eval.rs

@@ -18,10 +18,11 @@ use crate::{
 #[derive(Clone)]
 pub struct MiriConfig {
     pub validate: bool,
+    pub communicate: bool,
     pub args: Vec<String>,
 
     // The seed to use when non-determinism is required (e.g. getrandom())
-    pub seed: Option<u64>
+    pub seed: Option<u64>,
 }
 
 // Used by priroda.
@@ -158,7 +159,7 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
             cur_ptr = cur_ptr.offset(char_size, tcx)?;
         }
     }
- 
+
     assert!(args.next().is_none(), "start lang item has more arguments than expected");
 
     Ok(ecx)