cpp.info: Miscellaneous obsolete features
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Miscellaneous obsolete features
Here are a few more obsolete features.
* Attempting to paste two tokens which together do not form a valid
The preprocessor currently warns about this, and the resulting
preprocessed output is undefined. The tokens remain distinct if
the preprocessor is being used directly by the compiler front end.
Most of the time, when you get this warning, you will find that
`##' is being used superstitiously, to guard against whitespace
appearing between two tokens. It is almost always safe to delete
* `#pragma poison'
This is the same as `#pragma GCC poison'. The version without the
`GCC' prefix is deprecated. *Note Pragmas::.
* Multi-line string constants
GCC currently allows a string constant to extend across multiple
logical lines of the source file. This extension is deprecated
and will be removed in a future version of GCC. Such string
constants are already rejected in all directives apart from
Instead, make use of ISO C concatenation of adjacent string
literals, or use `\n' followed by a backslash-newline.
Created Mon Nov 8 17:42:11 2004 on tillpc with info_to_html version 0.9.6.