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<a name="Legacy-type-encoding"></a>
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Next: <a href="_0040encode.html#g_t_0040encode" accesskey="n" rel="next">@encode</a>, Up: <a href="Type-encoding.html#Type-encoding" accesskey="u" rel="up">Type encoding</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Legacy-Type-Encoding"></a>
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<h4 class="subsection">8.3.1 Legacy Type Encoding</h4>
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<p>Unfortunately, historically GCC used to have a number of bugs in its
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encoding code. The NeXT runtime expects GCC to emit type encodings in
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this historical format (compatible with GCC-3.3), so when using the
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NeXT runtime, GCC will introduce on purpose a number of incorrect
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encodings:
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</p>
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<ul>
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<li> the read-only qualifier of the pointee gets emitted before the ’^’.
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The read-only qualifier of the pointer itself gets ignored, unless it
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is a typedef. Also, the ’r’ is only emitted for the outermost type.
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</li><li> 32-bit longs are encoded as ’l’ or ’L’, but not always. For typedefs,
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the compiler uses ’i’ or ’I’ instead if encoding a struct field or a
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pointer.
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</li><li> <code>enum</code>s are always encoded as ’i’ (int) even if they are actually
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unsigned or long.
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</li></ul>
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<p>In addition to that, the NeXT runtime uses a different encoding for
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bitfields. It encodes them as <code>b</code> followed by the size, without
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a bit offset or the underlying field type.
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