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3 yıl önce
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  67. <a name="Weak-Pragmas-1"></a>
  68. <h4 class="subsection">6.62.12 Weak Pragmas</h4>
  69. <p>For compatibility with SVR4, GCC supports a set of <code>#pragma</code>
  70. directives for declaring symbols to be weak, and defining weak
  71. aliases.
  72. </p>
  73. <dl compact="compact">
  74. <dt><code>#pragma weak <var>symbol</var></code></dt>
  75. <dd><a name="index-pragma_002c-weak"></a>
  76. <p>This pragma declares <var>symbol</var> to be weak, as if the declaration
  77. had the attribute of the same name. The pragma may appear before
  78. or after the declaration of <var>symbol</var>. It is not an error for
  79. <var>symbol</var> to never be defined at all.
  80. </p>
  81. </dd>
  82. <dt><code>#pragma weak <var>symbol1</var> = <var>symbol2</var></code></dt>
  83. <dd><p>This pragma declares <var>symbol1</var> to be a weak alias of <var>symbol2</var>.
  84. It is an error if <var>symbol2</var> is not defined in the current
  85. translation unit.
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