Merge branch 'jk/doc-format-patch-skips-merges'

Document that "format-patch" skips merges.

* jk/doc-format-patch-skips-merges:
  docs/format-patch: mention handling of merges

Documentation/git-format-patch.txt

@@ -36,7 +36,7 @@ SYNOPSIS
 DESCRIPTION
 -----------
 
-Prepare each commit with its "patch" in
+Prepare each non-merge commit with its "patch" in
 one "message" per commit, formatted to resemble a UNIX mailbox.
 The output of this command is convenient for e-mail submission or
 for use with 'git am'.
@@ -740,6 +740,14 @@ use it only when you know the recipient uses Git to apply your patch.
 $ git format-patch -3
 ------------
 
+CAVEATS
+-------
+
+Note that `format-patch` will omit merge commits from the output, even
+if they are part of the requested range. A simple "patch" does not
+include enough information for the receiving end to reproduce the same
+merge commit.
+
 SEE ALSO
 --------
 linkgit:git-am[1], linkgit:git-send-email[1]