lint tutorial: hint on the discovered but not processed actions

Linting is a natural example where actions are discovered that are
not neded for the artifact that is requested to be built. Use this
opportunity to explain the difference between discovering an action
and processing it.

1 files changed, 10 insertions, 0 deletions

diff --git a/doc/tutorial/lint.md b/doc/tutorial/lint.md
index 3876da75..6005c5d1 100644
--- a/doc/tutorial/lint.md
+++ b/doc/tutorial/lint.md
@@ -342,6 +342,16 @@ INFO: Backing up artifacts of 1 export targets
 INFO: Target tainted ["lint"].
 ```
 
+Note the difference between the discovered and processed actions.
+This is inherent to the way linting works: in order to know the
+precise command line with which a source file is compiled, the
+respective target has to be analysed. However, to lint the source
+files, it is not necessary to actually build the binary whose
+source code should be linted. Of course, if a combined test target
+that includes linting as well as end-to-end tests is considered,
+the binary has to be built (and hence the actions processed) for
+other reasons.
+
 To see that some real linting is going on, let's modify one
 of our source files. Say, we'll make the greeting independent
 of the recipient.