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<title>The GNU Fortran Compiler: MALLOC</title>

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<hr>
<a name="MALLOC-_002d_002d_002d-Allocate-dynamic-memory"></a>
<h3 class="section">9.183 <code>MALLOC</code> &mdash; Allocate dynamic memory</h3>
<a name="index-MALLOC"></a>
<a name="index-pointer_002c-cray-1"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>MALLOC(SIZE)</code> allocates <var>SIZE</var> bytes of dynamic memory and
returns the address of the allocated memory. The <code>MALLOC</code> intrinsic
is an extension intended to be used with Cray pointers, and is provided
in GNU Fortran to allow the user to compile legacy code. For new code
using Fortran 95 pointers, the memory allocation intrinsic is
<code>ALLOCATE</code>.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>GNU extension
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Function
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><p><code>PTR = MALLOC(SIZE)</code>
</p>
</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>SIZE</var></td><td width="70%">The type shall be <code>INTEGER</code>.</td></tr>
</table>

</dd>
<dt><em>Return value</em>:</dt>
<dd><p>The return value is of type <code>INTEGER(K)</code>, with <var>K</var> such that
variables of type <code>INTEGER(K)</code> have the same size as
C pointers (<code>sizeof(void *)</code>).
</p>
</dd>
<dt><em>Example</em>:</dt>
<dd><p>The following example demonstrates the use of <code>MALLOC</code> and
<code>FREE</code> with Cray pointers.
</p>
<div class="smallexample">
<pre class="smallexample">program test_malloc
  implicit none
  integer i
  real*8 x(*), z
  pointer(ptr_x,x)

  ptr_x = malloc(20*8)
  do i = 1, 20
    x(i) = sqrt(1.0d0 / i)
  end do
  z = 0
  do i = 1, 20
    z = z + x(i)
    print *, z
  end do
  call free(ptr_x)
end program test_malloc
</pre></div>

</dd>
<dt><em>See also</em>:</dt>
<dd><p><a href="FREE.html#FREE">FREE</a>
</p></dd>
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