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| <h3 class="section">10.23 Value Sizes</h3> |
| |
| <p>Whenever <span class="sc">gdb</span> prints a value memory will be allocated within |
| <span class="sc">gdb</span> to hold the contents of the value. It is possible in |
| some languages with dynamic typing systems, that an invalid program |
| may indicate a value that is incorrectly large, this in turn may cause |
| <span class="sc">gdb</span> to try and allocate an overly large ammount of memory. |
| |
| |
| <a name="index-set-max_002dvalue_002dsize-832"></a> |
| <dl><dt><code>set max-value-size </code><var>bytes</var><dt><code>set max-value-size unlimited</code><dd>Set the maximum size of memory that <span class="sc">gdb</span> will allocate for the |
| contents of a value to <var>bytes</var>, trying to display a value that |
| requires more memory than that will result in an error. |
| |
| <p>Setting this variable does not effect values that have already been |
| allocated within <span class="sc">gdb</span>, only future allocations. |
| |
| <p>There's a minimum size that <code>max-value-size</code> can be set to in |
| order that <span class="sc">gdb</span> can still operate correctly, this minimum is |
| currently 16 bytes. |
| |
| <p>The limit applies to the results of some subexpressions as well as to |
| complete expressions. For example, an expression denoting a simple |
| integer component, such as <code>x.y.z</code>, may fail if the size of |
| <var>x.y</var> is dynamic and exceeds <var>bytes</var>. On the other hand, |
| <span class="sc">gdb</span> is sometimes clever; the expression <code>A[i]</code>, where |
| <var>A</var> is an array variable with non-constant size, will generally |
| succeed regardless of the bounds on <var>A</var>, as long as the component |
| size is less than <var>bytes</var>. |
| |
| <p>The default value of <code>max-value-size</code> is currently 64k. |
| |
| <p><a name="index-show-max_002dvalue_002dsize-833"></a><br><dt><code>show max-value-size</code><dd>Show the maximum size of memory, in bytes, that <span class="sc">gdb</span> will |
| allocate for the contents of a value. |
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