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<title>Pragma Scope in Precompiled Files</title>
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<h3>Pragma Scope in Precompiled Files</h3>
<p>Pragma settings inside a precompiled file affect only the source code within that file. The pragma settings for an item declared in a precompiled header file (such as data or a function) are saved then restored when the precompiled header file is included.</p>
<p>For example, the source code in Listing 5.3 specifies that the variable xxx is a far variable.</p>
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<h5>Listing 5.3 Pragma Settings in a Precompiled Header</h5>
<p>// my_pch.pch<br />
// Generate a precompiled header named pch.mch.</p>
<p>#pragma precompile_target "my_pch.mch" </p>
<p>#pragma far_data on<br />
extern int xxx;</p>
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<p>The source code in Listing 5.4 includes the precompiled version of Listing 5.3.</p>
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<h5>Listing 5.4 Pragma Settings in an Included Precompiled File</h5>
<p>// test.c<br />
#pragma far_data off // far data is disabled<br />
#include "my_pch.mch" // this precompiled file sets far_data on<br />
// far_data is still off but xxx is still a far variable</p>
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<p>The pragma setting in the precompiled file is active within the precompiled file, even though the source file including the precompiled file has a different setting.
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