x64 builds and Windows 7

[Ralf Habacker]

Casper van Donderen schrieb:
> Yeah, but you could also do it with a compiler flag... Then you don't
> have to change a lot...
>   
which could be initial set by
EMERGE_ARCHITECTURE=x64

while for 32 bit
    EMERGE_ARCHITECTURE=x86

-> This feature was just checked into emerge on kde svn
> with your solution you have to rename all packages (or also just
> append -x64 to the packagename)
>   
On linux 32 and 64 bit package are unique for a given architecture 
http://www.rpmseek.com/rpm-pl/kdelibs.html?hl=de&cs=kdelibs:PN:0:0:0:0:0 
and I am sure, that this should be also the same on windows. Otherwise 
this will end in a nightmare when people are mixing 32bit and 64 bit 
packages.

Also people may be required to install KDE/32bit also on a 64bit system, 
may be because a specific kde application is not available as 64bit 
version.
The installer could be easily fixed to support x64 packages as Patrick 
has done for mingw4.

BTW: emerge and the packager are already prepared for creating x64 
packages, so you can immediatly start to build x64 packages.  :-)

<snip>
>> If the 32 bit installer would be able to run on 64 bit systems and the
>> installer would be able to detect the 64bit os, the 64bit packages could
>> be preselected by default  (and the 32 bit packages when running on a 32
>> bit os)
>>     
this looks easy

BOOL Is64BitWindows()
{
#if defined(_WIN64)
 return TRUE;  // 64-bit programs run only on Win64
#elif defined(_WIN32)
 // 32-bit programs run on both 32-bit and 64-bit Windows
 // so must sniff
 BOOL f64 = FALSE;
 return IsWow64Process(GetCurrentProcess(), &f64) && f64;
#else
 return FALSE; // Win64 does not support Win16
#endif
}
http://blogs.msdn.com/oldnewthing/archive/2005/02/01/364563.aspx


>> Important questions with 64 bit systems I see are:
>>
>> - is it possible to load 32bit dll's from 64 dll's and 64bit executable ?
>>     
I found the answer ... 32-bit DLLs cannot be loaded in a 64-bit process. 
from 
http://social.msdn.microsoft.com/forums/en-US/wpf/thread/7b8fe815-90c5-4919-aa22-431287a93d81

This mean that *all* packages which kde packages deppends on have to be 
rebuild for x64.

Regards
Ralf