[Bug preprocessor/12075] non-terminated quotes within #if'ed out text comments confuse preprocessor

[ehrhardt at mathematik dot uni-ulm dot de]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12075


ehrhardt at mathematik dot uni-ulm dot de changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


------- Additional Comments From ehrhardt at mathematik dot uni-ulm dot de  2003-08-27 09:54 -------
Decomposing a file into preprocessing tokens is translations phase 3.
Preprocessing directives are executed in translation phase 4. This
means that even if text is skipped via #if 0 it must be a sequence of
preprocessing tokens.
In your example the double quote can not start a string constant
because a string constant must not contain a newline character (6.4.5[1]).
Note: This was accepted by older versions of gcc as an extension.
Hence the dobule quote character must be a preprocessing token of its own.
This invokes undefined behaviour (6.4[3]).

   regards  Christian