alt Hacker NewsThe one big challenge I've had with big legacy Win32/C++ codebases is migrating it fully from 32bit to 64bit. Loads of know-how and docs for complex GUI controls and structs are lost to time, or really fragmented. Other than that, yeah it really does all just work once you're past that.
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Well it's still a 32 bit program so I guess that helps. Would probably require some porting to make it 64 bit native, but as long as you use the WPARAM, INT_PTR typed and what not correctly it 'should just work'.
In 32-bit windows, you used to be able to see if a pointer was valid or not by seeing if it pointed to the last 2GB of address space. If it did, it was pointing to Kernel memory that was not valid for user mode code.
But then Large Address Aware (4GB limit) changes everything, and you can't do that anymore. In order for a program to be Large Address Aware, you need to not try to do things like check high bits of pointers, then every single library and DLL you use also needs to do the same.
Doesn't WINE have pretty decent documentation by now from all the reverse engineering?
I went through that a few years ago and it actually went pretty smoothly. There were a few UINT_PTR or DWORD_PTR changes I had to get used to and a couple of string glitches (we mostly used the _T() macro for strings and already used the _t variants of string functions in the original code, so that helped).
The biggest problems were DAO (database) and a few COM controls that were not available in x64.