Add CI runs on rustc beta on Windows and MacOS

This should catch any platform-specific behavior changes in rustc
before they land in stable.

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 5b886e19bff5d440cdabb8441b4e4a9d17077fdb..7d9cf422aca59bed4ed4bbce21b9c1507facbc20 100644 (file)
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -26,10 +26,18 @@ jobs:
             platform: macos-latest
             build-net-tokio: true
             build-no-std: true
+          - toolchain: beta
+            platform: macos-latest
+            build-net-tokio: true
+            build-no-std: true
           - toolchain: stable
             platform: windows-latest
             build-net-tokio: true
             build-no-std: true
+          - toolchain: beta
+            platform: windows-latest
+            build-net-tokio: true
+            build-no-std: true
           - toolchain: beta
             build-net-tokio: true
             build-no-std: true