Move comments

src/cargo/core/package.rs

@@ -188,6 +188,12 @@ impl Package {
 
     /// Returns explicit kinds either forced by `forced-target` in `Cargo.toml`,
     /// fallback to `default-target`, or specified in cli parameters.
+    ///
+    /// If `--target` has not been specified, then the return value
+    /// is the same as if `--target $HOST` was specified. See
+    /// `rebuild_unit_graph_shared` for why callers want to do this.
+    ///  However, if the package has its own `package.default-target`
+    ///  key, then that gets used instead of `$HOST`
     pub fn explicit_kinds(
         &self,
         requested_kinds: &[CompileKind],

src/cargo/ops/cargo_compile.rs

@@ -1047,12 +1047,6 @@ fn generate_targets(
             let features_for = FeaturesFor::from_for_host(target.proc_macro());
             let features = resolved_features.activated_features(pkg.package_id(), features_for);
 
-            // If `--target` has not been specified, then the unit
-            // graph is built almost like if `--target $HOST` was
-            // specified. See `rebuild_unit_graph_shared` for more on
-            // why this is done. However, if the package has its own
-            // `package.target` key, then this gets used instead of
-            // `$HOST`
             let explicit_kinds = pkg.explicit_kinds(requested_kinds, explicit_host_kind);
 
             for kind in explicit_kinds.iter() {