Add highlighting of the F2008 keyword "impure"

* lisp/progmodes/f90.el (f90-keywords-re): Highlight F2008 keyword
"impure" (bug#51529).

diff --git a/lisp/progmodes/f90.el b/lisp/progmodes/f90.el
index f9e6101e7ab5ae80d88aa87b3093880c8c12c375..acc0d96ea5bb3222accf50c57e81576f9c483bbc 100644 (file)
--- a/lisp/progmodes/f90.el
+++ b/lisp/progmodes/f90.el
@@ -345,6 +345,7 @@ The options are `downcase-word', `upcase-word', `capitalize-word' and nil."
                  ;; there are spaces.
                  "contiguous" "submodule" "concurrent" "codimension"
                  "sync all" "sync memory" "critical" "image_index" "error stop"
+                 "impure"
                  ))
    "\\_>")
   "Regexp used by the function `f90-change-keywords'.")