Merge from trunk (r239915 to r240230)fortran-dev

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/fortran-dev@240290 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 98 insertions, 6 deletions

diff --git a/libcpp/include/line-map.h b/libcpp/include/line-map.h
index bef77957ffe..747609d4393 100644
--- a/libcpp/include/line-map.h
+++ b/libcpp/include/line-map.h
@@ -1484,7 +1484,86 @@ class fixit_hint;
    - range 0 is at the "%s" with start = caret = "%" and finish at
      the "s".
    - range 1 has start/finish covering the "101" and is not flagged for
-     caret printing; it is perhaps at the start of "101".  */
+     caret printing; it is perhaps at the start of "101".
+
+
+   Fix-it hints
+   ------------
+
+   Rich locations can also contain "fix-it hints", giving suggestions
+   for the user on how to edit their code to fix a problem.  These
+   can be expressed as insertions, replacements, and removals of text.
+   The edits by default are relative to the zeroth range within the
+   rich_location, but optionally they can be expressed relative to
+   other locations (using various overloaded methods of the form
+   rich_location::add_fixit_*).
+
+   For example:
+
+   Example F: fix-it hint: insert_before
+   *************************************
+      ptr = arr[0];
+	    ^~~~~~
+	    &
+   This rich location has a single range (range 0) covering "arr[0]",
+   with the caret at the start.  The rich location has a single
+   insertion fix-it hint, inserted before range 0, added via
+     richloc.add_fixit_insert_before ("&");
+
+   Example G: multiple fix-it hints: insert_before and insert_after
+   ****************************************************************
+      #define FN(ARG0, ARG1, ARG2) fn(ARG0, ARG1, ARG2)
+				      ^~~~  ^~~~  ^~~~
+				      (   ) (   ) (   )
+   This rich location has three ranges, covering "arg0", "arg1",
+   and "arg2", all with caret-printing enabled.
+   The rich location has 6 insertion fix-it hints: each arg
+   has a pair of insertion fix-it hints, suggesting wrapping
+   them with parentheses: one a '(' inserted before,
+   the other a ')' inserted after, added via
+     richloc.add_fixit_insert_before (LOC, "(");
+   and
+     richloc.add_fixit_insert_after (LOC, ")");
+
+   Example H: fix-it hint: removal
+   *******************************
+     struct s {int i};;
+		      ^
+		      -
+   This rich location has a single range at the stray trailing
+   semicolon, along with a single removal fix-it hint, covering
+   the same range, added via:
+     richloc.add_fixit_remove ();
+
+   Example I: fix-it hint: replace
+   *******************************
+      c = s.colour;
+	    ^~~~~~
+	    color
+   This rich location has a single range (range 0) covering "colour",
+   and a single "replace" fix-it hint, covering the same range,
+   added via
+     richloc.add_fixit_replace ("color");
+
+   Adding a fix-it hint can fail: for example, attempts to insert content
+   at the transition between two line maps may fail due to there being no
+   source_location (aka location_t) value to express the new location.
+
+   Attempts to add a fix-it hint within a macro expansion will fail.
+
+   We do not yet support newlines in fix-it text; attempts to do so will fail.
+
+   The rich_location API handles these failures gracefully, so that
+   diagnostics can attempt to add fix-it hints without each needing
+   extensive checking.
+
+   Fix-it hints within a rich_location are "atomic": if any hints can't
+   be applied, none of them will be (tracked by the m_seen_impossible_fixit
+   flag), and no fix-its hints will be displayed for that rich_location.
+   This implies that diagnostic messages need to be worded in such a way
+   that they make sense whether or not the fix-it hints are displayed,
+   or that richloc.seen_impossible_fixit_p () should be checked before
+   issuing the diagnostics.  */
 
 class rich_location
 {
@@ -1522,14 +1601,25 @@ class rich_location
 
   /* Methods for adding insertion fix-it hints.  */
 
-  /* Suggest inserting NEW_CONTENT at the primary range's caret.  */
+  /* Suggest inserting NEW_CONTENT immediately before the primary
+     range's start.  */
   void
-  add_fixit_insert (const char *new_content);
+  add_fixit_insert_before (const char *new_content);
 
-  /* Suggest inserting NEW_CONTENT at WHERE.  */
+  /* Suggest inserting NEW_CONTENT immediately before the start of WHERE.  */
   void
-  add_fixit_insert (source_location where,
-		    const char *new_content);
+  add_fixit_insert_before (source_location where,
+			   const char *new_content);
+
+  /* Suggest inserting NEW_CONTENT immediately after the end of the primary
+     range.  */
+  void
+  add_fixit_insert_after (const char *new_content);
+
+  /* Suggest inserting NEW_CONTENT immediately after the end of WHERE.  */
+  void
+  add_fixit_insert_after (source_location where,
+			  const char *new_content);
 
   /* Methods for adding removal fix-it hints.  */
 
@@ -1567,9 +1657,11 @@ class rich_location
   unsigned int get_num_fixit_hints () const { return m_fixit_hints.count (); }
   fixit_hint *get_fixit_hint (int idx) const { return m_fixit_hints[idx]; }
   fixit_hint *get_last_fixit_hint () const;
+  bool seen_impossible_fixit_p () const { return m_seen_impossible_fixit; }
 
 private:
   bool reject_impossible_fixit (source_location where);
+  void stop_supporting_fixits ();
   void add_fixit (fixit_hint *hint);
 
 public: