The HTML documentation page “20.5.2 Infinity and NaN” (http://www.gnu.org/software/libc/manual/html_node/Infinity-and-NaN.html) has incorrectly double-escaped HTML character entities for infinity & pi symbols. The infinity entity code being used is “∞” when it should be just “∞”, and the pi entity code being used is “@amp;pi;” when it should be just “π”. The result is that currently the rendered HTML shows “@infin;” and “π” instead of “∞” and “π”.
The https://www.gnu.org/software/libc/manual/html_node/Parsing-of-Floats.html page also has the ∞ entity in the description of strtod.
And also https://www.gnu.org/software/libc/manual/html_node/Math-Error-Reporting.html
Looks like a Texinfo regression/behavioral change. I'll see if I can fix this on the glibc side.
Patch posted: https://sourceware.org/pipermail/libc-alpha/2020-July/116357.html
Fixed in glibc 2.32: commit da7d62b50396c8b6d67c1ba800a196e83e2ec469 Author: Florian Weimer <fweimer@redhat.com> Date: Thu Jul 16 10:17:31 2020 +0200 manual: Use Unicode instead HTML entities for characters (bug 19737) Texinfo no longer treats arguments to @set in @ifhtml blocks as literal HTML, so the & in the entity references was encoded as @amp; in HTML. Using the equivalent Unicode characters avoids this issue. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>