longer fails an assertion under debugging builds. This was a regression
from 5.20. [perl #126482]
+=item *
+
+Many issues relating to C<printf "%a"> of hexadecimal floating point
+were fixed. In addition, the "subnormals" (formerly known as "denormals")
+floating point anumbers are now supported both with the plain IEEE 754
+floating point numbers (64-bit or 128-bit) and the x86 80-bit
+"extended precision". Note that subnormal hexadecimal floating
+point literals will give a warning about "exponent underflow".
+[perl #128843, #128889, #128890, #128893, #128909, #128919]
+
=back
=head1 Known Problems