+@vindex fortran-directive-re
+ Compiler directive lines, or preprocessor lines, have much the same
+appearance as comment lines. It is important, though, that such lines
+never be indented at all, no matter what the value of
+@code{fortran-comment-indent-style}. The variable
+@code{fortran-directive-re} is a regular expression that specifies which
+lines are directives. Matching lines are never indented, and receive
+distinctive font-locking.
+