Re: BUG #8608: ECPG: sizeof() in EXEC SQL DECLARE SECTION

2013-11-25 09:18 keltezéssel, Michael Meskes írta:
> On Sun, Nov 24, 2013 at 03:59:40PM +0100, Boszormenyi Zoltan wrote:
>> I think it's needlessly narrows the scope of the problem.
>> Consider this code:
>>
>> #include <stdio.h>
>>
>> #define hide_size_of_var sizeof
>> ...
> I assume you'd want to put this defined name into a declare section, right?
> Well, that's what EXEC SQL DECLARE is for, isn't it?

Of course. And of course you meant EXEC SQL DEFINE.

The attached code throws syntax errors over sizeof(int) and
sizeof(struct somestruct). I compiled GIT HEAD which contains your fix:

commit 08d1b22b3be2305ad6b83ca275829ff26305f5d7
Author: Michael Meskes <meskes(at)postgresql(dot)org>
Date: Sun Nov 24 12:51:21 2013 +0100

Allow C array definitions to use sizeof().

When parsing C variable definitions ecpg should allow sizeof() operators as array
dimensions.

So it seems it's not enough, try these with the attached code:

Succeeds:
$ ecpg array-sizeof.pgc

These fail:
$ ecpg -D TRY_INT array-sizeof.pgc
array-sizeof.pgc:24: ERROR: syntax error at or near "int"

$ ecpg -D TRY_STRUCT array-sizeof.pgc
array-sizeof.pgc:30: ERROR: syntax error at or near "struct"

The attached patch fixes "sizeof(struct something)" but the
"simple_type" variant that should also accept
[signed|unsigned]{char|short|int|long|long long}
causes 2 shift/reduce problems when processing preproc.y.

Best regards,
Zoltán Böszörményi

>
>> I think you should pass everything through as is inside the '[' and ']' and
>> let the C compiler fail if the code is not valid.
> I prefer catching as much as possible without re-implementing a C-compiler of course.
>
> Michael

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Zoltán Böszörményi
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