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From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Winter Loo" <winterloo@126.com>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: [ecpg bug]: can not use single '*' in multi-line comment after c preprocessor directives
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Comments: In-reply-to "Winter Loo" <winterloo@126.com>
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"Winter Loo" <winterloo@126.com> writes:
> The following code fails to pass the ecpg compilation, although it is ac=
cepted by the gcc compiler.

Yeah ... an isolated "/" inside the comment doesn't work either.

> Confused! I am uncertain how to rectify the regex. I hope someone can ad=
dress this bug.

I poked at this for awhile and concluded that we probably cannot make
it work with a single regexp for "cppline".  The right thing would
involve an exclusive start condition for parsing a cppline, more or
less like the way that /* comments are parsed in the <xc> start
condition.  This is kind of a lot of work compared to the value :-(.
Maybe somebody else would like to take a crack at it, but I can't
get excited enough about it.

There are other deficiencies too in ecpg's handling of these things,
like the fact that (I think) comments are mishandled in #include
directives.

			regards, tom lane