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diff --git a/share/doc/gcc/Hex-Floats.html b/share/doc/gcc/Hex-Floats.html new file mode 100644 index 0000000..eb22a5e --- /dev/null +++ b/share/doc/gcc/Hex-Floats.html @@ -0,0 +1,105 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- This file documents the use of the GNU compilers. + +Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). 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As a GNU extension, GCC +supports this in C90 mode (except in some cases when strictly +conforming) and in C++98, C++11 and C++14 modes. In that format the +‘<samp>0x</samp>’ hex introducer and the ‘<samp>p</samp>’ or ‘<samp>P</samp>’ exponent field are +mandatory. The exponent is a decimal number that indicates the power of +2 by which the significant part is multiplied. Thus ‘<samp>0x1.f</samp>’ is +1 15/16, +‘<samp>p3</samp>’ multiplies it by 8, and the value of <code>0x1.fp3</code> +is the same as <code>1.55e1</code>. +</p> +<p>Unlike for floating-point numbers in the decimal notation the exponent +is always required in the hexadecimal notation. Otherwise the compiler +would not be able to resolve the ambiguity of, e.g., <code>0x1.f</code>. This +could mean <code>1.0f</code> or <code>1.9375</code> since ‘<samp>f</samp>’ is also the +extension for floating-point constants of type <code>float</code>. +</p> + + + +</body> +</html> |