[php-maint] Bug#613982: Acknowledgement (printf generates scientific notation inaccurately)

[Ronan]

This message is probably of no interest to anyone
but myself.  Forgive me for sending it, but I want
to correct an error that I made.

I said that a precision of 52 decimal digits "allows
all IEEE double-precision floating-point numbers to
be output with perfect accuracy".  This is woefully
wrong; a counter-example is the number pow(2, -1024).