diff --git a/.appveyor.yml b/.appveyor.yml
index 2474657fd77..3fe85fe1421 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -31,7 +31,7 @@ install:
     - rustup component remove rust-docs & exit 0
     - rustup update
     # Install "master" toolchain
-    - cargo install rustup-toolchain-install-master & exit 0
+    - cargo install rustup-toolchain-install-master -f
     - rustup-toolchain-install-master -f -n master %RUSTC_HASH% -c rust-src -c rustc-dev
     - rustup default master
     - rustc --version
diff --git a/.travis.yml b/.travis.yml
index bb38510e393..e9df794b594 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -38,7 +38,7 @@ before_script:
 - rustup component remove rust-docs || echo "rust-docs already gone"
 - rustup update
 # Install "master" toolchain
-- cargo install rustup-toolchain-install-master || echo "rustup-toolchain-install-master already installed"
+- cargo install rustup-toolchain-install-master -f
 - travis_retry rustup-toolchain-install-master -f -n master $RUSTC_HASH -c rust-src -c rustc-dev
 - rustup default master
 - rustc --version