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Denormalized numbers can also be troublesome because some functions have implementation-defined behavior when used with denormalized values. For example, using the %a or $%A conversion specifier in a format string can produce implementation-defined results when applied to denormalized numbers.
Section Subclause 7.21.6.1, paragraph 8, of the C Standard [ISO/IEC 9899:2011], states:
A double argument representing a floating-point number is converted in the style
[-]0xh.hhhh p±d, where there is one hexadecimal digit (which is nonzero if the argument is a normalized floating-point number and is otherwise unspecified) before the decimal-point character.
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| [Bryant 2003] | Section 2.4, "Floating Point" |
| [IEEE 754] | |
| [ISO/IEC 9899:2011] | Section Subclause 7.21.6.1, "The fprintf Function" |
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