install-compile-source.md: also explain building snapshots
The question on how to build a snapshot version of bazel arises
frequently, when a fix for a bug is submitted and people want to
try the fixe immediately. Therefore, add a paragraph to the
compile-from-source instructions, explaining how to do this.
@@ -56,8 +56,11 @@ Ensure you have installed:
### 2. Download and unpack Bazel's source files (distribution archive)
-Download `bazel-<version>-dist.zip` from [GitHub](https://github.com/bazelbuild/bazel/releases),
-e.g. `bazel-0.15.2-dist.zip`.
+Download `bazel-<version>-dist.zip` from [GitHub](https://github.com/bazelbuild/bazel/releases)
+(for example, `bazel-0.15.2-dist.zip`). If you want to build a development snapshot of
+Bazel, download the archive for the latest release before the snapshot
+you are interested in as you need to bootstrap that version of Bazel
+first in order to build the snapshot version.
**Note:** There is a **single, architecture-independent** distribution archive. There are no architecture-specific or OS-specific distribution archives.
@@ -126,3 +129,9 @@ Bazel binary, without an embedded JDK. You can copy it to a directory within the
You don't need to run Bazel from the MSYS2 shell. You can run Bazel from the
Command Prompt (`cmd.exe`) or PowerShell.
+
+### 4. Development snapshots of Bazel
+
+Once you have a reasonably new working `bazel` binary, you can also build
+snapshot versions of Bazel by checking out the commit you're interested in
+and build a new version of Bazel by `bazel build //src:bazel`.
