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1 @c Copyright (C) 2002 Free Software Foundation, Inc.
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2 @c This is part of the GCC manual.
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3 @c For copying conditions, see the file gcc.texi.
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4
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5 @node Languages
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6 @chapter Language Front Ends in GCC
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7
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8 The interface to front ends for languages in GCC, and in particular
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9 the @code{tree} structure (@pxref{Trees}), was initially designed for
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10 C, and many aspects of it are still somewhat biased towards C and
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11 C-like languages. It is, however, reasonably well suited to other
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12 procedural languages, and front ends for many such languages have been
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13 written for GCC@.
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14
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15 Writing a compiler as a front end for GCC, rather than compiling
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16 directly to assembler or generating C code which is then compiled by
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17 GCC, has several advantages:
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18
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19 @itemize @bullet
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20 @item GCC front ends benefit from the support for many different
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21 target machines already present in GCC@.
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22 @item GCC front ends benefit from all the optimizations in GCC@. Some
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23 of these, such as alias analysis, may work better when GCC is
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24 compiling directly from source code then when it is compiling from
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25 generated C code.
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26 @item Better debugging information is generated when compiling
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27 directly from source code than when going via intermediate generated C
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28 code.
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29 @end itemize
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30
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31 Because of the advantages of writing a compiler as a GCC front end,
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32 GCC front ends have also been created for languages very different
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33 from those for which GCC was designed, such as the declarative
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34 logic/functional language Mercury. For these reasons, it may also be
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35 useful to implement compilers created for specialized purposes (for
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36 example, as part of a research project) as GCC front ends.
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