Mention `no merge policy` in the CONTRIBUTING guide

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index e785f03d7de2b574c3b76b4c271bd8c77fabd665..5757773e12203f784271d3cbdfc9ccc1ee9a4a0d 100644 (file)
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -119,6 +119,13 @@ bring those changes into the source repository.
 
 Please make pull requests against the `master` branch.
 
+Rust follows a no merge policy, meaning, when you encounter merge
+conflicts you are expected to always rebase instead of merge.
+E.g. always use rebase when bringing the latest changes from
+the master branch to your feature branch.
+Also, please make sure that fixup commits are squashed into other related
+commits with meaningful commit messages.
+
 Please make sure your pull request is in compliance with Rust's style
 guidelines by running