Re: narwhal and PGDLLIMPORT

On 02/06/2014 10:14 AM, Craig Ringer wrote:
> On 02/05/2014 01:52 PM, Tom Lane wrote:
>> Craig Ringer <craig(at)2ndquadrant(dot)com> writes:
>>> On 02/05/2014 06:29 AM, Tom Lane wrote:
>>>> I had been okay with the manual PGDLLIMPORT-sprinkling approach
>>>> (not happy with it, of course, but prepared to tolerate it) as long
>>>> as I believed the buildfarm would reliably tell us of the need for
>>>> it. That assumption has now been conclusively disproven, though.
>>
>>> I'm kind of horrified that the dynamic linker doesn't throw its toys
>>> when it sees this.
>>
>> Indeed :-(.
>>
>> The truly strange part of this is that it seems that the one Windows
>> buildfarm member that's telling the truth (or most nearly so, anyway)
>> is narwhal, which appears to have the oldest and cruftiest toolchain
>> of the lot. I'd really like to come out the other end of this
>> investigation with a clear understanding of why the newer toolchains
>> are failing to report a link problem, and yet not building working
>> executables.
>
> I've done some digging and asked for some input from people with
> appropriate knowledge. Getting a hard answer's going to require some
> quality time with a debugger that I won't have until after the CF.

... though this link may shed some light, it turns out:

http://msdn.microsoft.com/en-us/library/aa271769(v=vs.60).aspx

So, yeah. It looks like we're probably linking to thunk functions as
data (ouch). To produce the desired error if __declspec(dllimport) is
missing we need to change gendefs.pl to emit DATA for exported globals.

--
Craig Ringer http://www.2ndQuadrant.com/
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