org-export: Make results of named code blocks a valid link target

* lisp/ox.el (org-export-search-cells): Use #+RESULTS keyword as
search cell when #+NAME is not provided.  Update the docstring
accordingly.
(org-export-resolve-fuzzy-link): Update the docstring.

* doc/org-manual.org (Exporting Code Blocks): Document the new
behavior and explain the details of exporting links to named code
blocks/results.

Fixes https://orgmode.org/list/010201826cb68597-bf75d596-7890-4dd0-b9ff-0c7b617b4dd4-000000@eu-west-1.amazonses.com

doc/org-manual.org

@@ -18369,6 +18369,36 @@ file is exported to, say, HTML or LaTeX formats.
   exported file.  Whether the code is evaluated at all depends on
   other options.  Example: =:exports none=.
 
+If a source block is named using =NAME= keyword, the same name will be
+assigned to the results of evaluation.  This way, fuzzy links pointing
+to the named source blocks exported using =:exports results= will
+remain valid and point to the results of evaluation.
+
+Results of evaluation of a named block can also be explicitly named
+using a separate =NAME= keyword.  The name value set via =NAME=
+keyword will be preferred over the parent source block.
+
+: #+NAME: code name
+: #+BEGIN_SRC emacs-lisp :exports both value
+: (+ 1 2)
+: #+END_SRC
+:
+: #+NAME: results name
+: #+RESULTS: code name
+: 3
+:
+: This [[code name][link]] will point to the code block.
+: Another [[results name][link]] will point to the results.
+
+Explicit setting of the result name may be necessary when a named code
+block is exported using =:exports both=.  Links to such block may
+arbitrarily point either to the code block or to its results when
+results do not have a distinct name.
+
+Note that all the links pointing to a source block exported using
+=:exports none= will be broken.  This will make export process fail,
+unless broken links are allowed during export (see [[*Export Settings]]). 
+
 #+vindex: org-export-use-babel
 To stop Org from evaluating code blocks to speed exports, use the
 header argument =:eval never-export= (see [[*Evaluating Code Blocks]]).

lisp/ox.el

@@ -4305,7 +4305,7 @@ A search cell follows the pattern (TYPE . SEARCH) where
     - target's or radio-target's name as a list of strings if
       TYPE is `target'.
 
-    - NAME affiliated keyword if TYPE is `other'.
+    - NAME or RESULTS affiliated keyword if TYPE is `other'.
 
 A search cell is the internal representation of a fuzzy link.  It
 ignores white spaces and statistics cookies, if applicable."
@@ -4323,7 +4323,8 @@ ignores white spaces and statistics cookies, if applicable."
 		(and custom-id (cons 'custom-id custom-id)))))))
     (`target
      (list (cons 'target (split-string (org-element-property :value datum)))))
-    ((and (let name (org-element-property :name datum))
+    ((and (let name (or (org-element-property :name datum)
+                        (car (org-element-property :results datum))))
 	  (guard name))
      (list (cons 'other (split-string name))))
     (_ nil)))
@@ -4355,8 +4356,9 @@ Return value can be an object or an element:
 
 - If LINK path matches a target object (i.e. <<path>>) return it.
 
-- If LINK path exactly matches the name affiliated keyword
-  (i.e. #+NAME: path) of an element, return that element.
+- If LINK path exactly matches the name or results affiliated keyword
+  (i.e. #+NAME: path or #+RESULTS: name) of an element, return that
+  element.
 
 - If LINK path exactly matches any headline name, return that
   element.