| @c Copyright (C) 2002 Free Software Foundation, Inc. |
| @c This is part of the GCC manual. |
| @c For copying conditions, see the file gcc.texi. |
| |
| @node Languages |
| @chapter Language Front Ends in GCC |
| |
| The interface to front ends for languages in GCC, and in particular |
| the @code{tree} structure (@pxref{Trees}), was initially designed for |
| C, and many aspects of it are still somewhat biased towards C and |
| C-like languages. It is, however, reasonably well suited to other |
| procedural languages, and front ends for many such languages have been |
| written for GCC@. |
| |
| Writing a compiler as a front end for GCC, rather than compiling |
| directly to assembler or generating C code which is then compiled by |
| GCC, has several advantages: |
| |
| @itemize @bullet |
| @item GCC front ends benefit from the support for many different |
| target machines already present in GCC@. |
| @item GCC front ends benefit from all the optimizations in GCC@. Some |
| of these, such as alias analysis, may work better when GCC is |
| compiling directly from source code then when it is compiling from |
| generated C code. |
| @item Better debugging information is generated when compiling |
| directly from source code than when going via intermediate generated C |
| code. |
| @end itemize |
| |
| Because of the advantages of writing a compiler as a GCC front end, |
| GCC front ends have also been created for languages very different |
| from those for which GCC was designed, such as the declarative |
| logic/functional language Mercury. For these reasons, it may also be |
| useful to implement compilers created for specialized purposes (for |
| example, as part of a research project) as GCC front ends. |
