Update to rust 1.48 toolchain to support unsafe extern block
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 26b2722..be15d31 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -15,8 +15,8 @@
         include:
           - rust: nightly
           - rust: beta
-          - rust: stable
-          - rust: 1.43.0
+          #- rust: stable
+          #- rust: 1.48.0
           - name: macOS
             rust: nightly
             os: macos
@@ -51,7 +51,7 @@
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: dtolnay/rust-toolchain@stable
+      - uses: dtolnay/rust-toolchain@beta
       - uses: actions/setup-java@v1
         with:
           java-version: 11
diff --git a/README.md b/README.md
index 28f9ef1..0ae6686 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@
 cxx-build = "0.5"
 ```
 
-*Compiler support: requires rustc 1.43+ and c++11 or newer*<br>
+*Compiler support: requires rustc 1.48+ and c++11 or newer*<br>
 *[Release notes](https://github.com/dtolnay/cxx/releases)*
 
 <br>
diff --git a/WORKSPACE b/WORKSPACE
index 6093eee..3fc2f90 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -25,15 +25,17 @@
 load("@io_bazel_rules_rust//rust:repositories.bzl", "rust_repository_set")
 
 rust_repository_set(
-    name = "rust_1_47_linux",
+    name = "rust_1_48_beta_linux",
     exec_triple = "x86_64-unknown-linux-gnu",
-    version = "1.47.0",
+    iso_date = "2020-11-08",
+    version = "beta",
 )
 
 rust_repository_set(
-    name = "rust_1_47_darwin",
+    name = "rust_1_48_beta_darwin",
     exec_triple = "x86_64-apple-darwin",
-    version = "1.47.0",
+    iso_date = "2020-11-08",
+    version = "beta",
 )
 
 vendor(
diff --git a/src/lib.rs b/src/lib.rs
index 091c7cc..04266fb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -18,7 +18,7 @@
 //!
 //! <br>
 //!
-//! *Compiler support: requires rustc 1.43+ and c++11 or newer*<br>
+//! *Compiler support: requires rustc 1.48+ and c++11 or newer*<br>
 //! *[Release notes](https://github.com/dtolnay/cxx/releases)*
 //!
 //! <br>