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Re: RFC: Cygwin 64 bit?
On Jan 18 15:54, Corinna Vinschen wrote:
> On Jan 18 14:23, Pedro Alves wrote:
> > I was looking for a technical reason that's worse, other then the
> > amount of mechanical work, which I'm sure could also be easily
> > scripted, with the long/int hidden behind a #define,
> > from the perspective of code that uses the headers. It's obvious
> > the pragma is less intrusive to the headers.
>
> I can't think of any. In both cases you will get the type mismatches in
> certain circumstances within the LP64 code of the application.
>
> Hmm. The only other problem I could see with the #pragma approach is a
> potential clash of debug information within the same CU. If you use
> Windows headers you would potentially have two entries for long in
> .debug_info:
>
> From the LLP64 code:
>
> <1><d0>: Abbrev Number: 2 (DW_TAG_base_type)
> <d1> DW_AT_byte_size : 4
> <d2> DW_AT_encoding : 5 (signed)
> <d3> DW_AT_name : long int
>
> From the LP64 code in the same CU:
>
> <1><dc>: Abbrev Number: 2 (DW_TAG_base_type)
> <dd> DW_AT_byte_size : 8
> <de> DW_AT_encoding : 5 (signed)
> <df> DW_AT_name : long int
That won't be the case, fortunately. A collegue has created a POC patch
which would result in only one entry for long, the "right" one with
DW_AT_byte_size 8, while the LLP64 usage of long would be converted to
the type int internally.
Corinna
--
Corinna Vinschen Please, send mails regarding Cygwin to
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