Editing Long double

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The range of a <code>long double</code> can be checked in C using <code><float.h></code> and C++ using <code>std::numeric_limits</code>. This 80-bit format typically has a range of roughly 1.9E-4932 ... 1.1E+4932 and holds 19-20 significant digits.
 
The range of a <code>long double</code> can be checked in C using <code><float.h></code> and C++ using <code>std::numeric_limits</code>. This 80-bit format typically has a range of roughly 1.9E-4932 ... 1.1E+4932 and holds 19-20 significant digits.
  
Even though the <code>long double</code> may be stored using 96 or even 128 bits (you can check the number of bits using <code>8*sizeof(long double)</code>), it still only has 80 bits of precision. The extra padding bits are to help modern architectures align to 8 or 16 bit boundaries. In GCC, the compiler switches <code>-m96bit-long-double</code> and <code>-m128bit-long-double</code> may be used to control the storage size of a <code>long double</code>, without of course, changing its precision in any way.
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Even though the <code>long double</code> may be stored using 96 or even 128 bits (you can check the number of bits using <code>4*sizeof(long double)</code>), it still only has 80 bits of precision. The extra padding bits are to help modern architectures align to 8 or 16 bit boundaries. In GCC, the compiler switches <code>-m96bit-long-double</code> and <code>-m128bit-long-double</code> may be used to control the storage size of a <code>long double</code>, without of course, changing its precision in any way.
  
 
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