Auto merge of #49939 - kennytm:rollup, r=kennytm

Rollup of 14 pull requests

Successful merges: #49908, #49876, #49916, #49951, #49465, #49922, #49866, #49915, #49886, #49913, #49852, #49958, #49871, #49864

Failed merges:

Author: bors

.travis.yml

@@ -176,6 +176,8 @@ matrix:
       if: branch = auto
     - env: IMAGE=x86_64-gnu-distcheck
       if: branch = auto
+    - env: IMAGE=mingw-check
+      if: type = pull_request OR branch = auto
 
     - stage: publish toolstate
       if: branch = master AND type = push

src/bootstrap/bin/rustc.rs

@@ -247,9 +247,6 @@ 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") {
             cmd.arg("-Zalways-encode-mir");
-            if stage != "0" {
-                cmd.arg("-Zmiri");
-            }
             cmd.arg("-Zmir-emit-validate=1");
         }