In fragment identifiers, use ~%d for ordinal suffixes,

and reserve the character '~' for that purpose.

Bug found by validator.w3.org in openssl(1), which contains both a
tag "tls1_2" and a second instance of a tag "tls1", which also resulted
in "tls1_2", causing a clash.  Now, the second instance of "tls1" is
rendered as "tls1~2" instead, employing the newly reserved '~'.

2 files changed, 3 insertions, 3 deletions

diff --git a/regress/usr.bin/mandoc/mdoc/Bd/nested.out_html b/regress/usr.bin/mandoc/mdoc/Bd/nested.out_html
index bc71c2700f2..9476189599a 100644
--- a/regress/usr.bin/mandoc/mdoc/Bd/nested.out_html
+++ b/regress/usr.bin/mandoc/mdoc/Bd/nested.out_html
@@ -8,10 +8,10 @@
 outer text</div>
 regular text
 <div class="Bd Pp
-  Bd-indent" id="outer_2"><a class="permalink" href="#outer_2">outer</a> text
+  Bd-indent" id="outer~2"><a class="permalink" href="#outer~2">outer</a> text
   (4n)
 <div class="Bd Pp
-  Bd-indent" id="inner_2"><a class="permalink" href="#inner_2">inner</a> text
+  Bd-indent" id="inner~2"><a class="permalink" href="#inner~2">inner</a> text
   (2n)</div>
 outer text
 <dl class="Bl-tag">
diff --git a/regress/usr.bin/mandoc/mdoc/Sh/tag.out_html b/regress/usr.bin/mandoc/mdoc/Sh/tag.out_html
index d99c6d4da69..0dd39398470 100644
--- a/regress/usr.bin/mandoc/mdoc/Sh/tag.out_html
+++ b/regress/usr.bin/mandoc/mdoc/Sh/tag.out_html
@@ -2,7 +2,7 @@
 </section>
 </section>
 <section class="Sh">
-<h1 class="Sh" id="DESCRIPTION_2"><a class="permalink" href="#DESCRIPTION_2">DESCRIPTION</a></h1>
+<h1 class="Sh" id="DESCRIPTION~2"><a class="permalink" href="#DESCRIPTION~2">DESCRIPTION</a></h1>
 <p class="Pp">Text in duplicate description section.</p>
 </section>
 <section class="Sh">