I don't know enough about implib to explain it.
But another method that I believe should work is to use linker
definition files.
It'll allow optlink to work.
Just add it to dmd, actually I believe it needs to be passed to
Optlink (so -L it).
Another fix, might be to use 64bit, but shouldn't be required.
[0]
http://www.dsource.org/projects/bindings/wiki/DefFiles/OleAut32
Rikki,
Thank you for your kind attention. I spewed to the newsgroup and
googled for an answer in the wrong order. It appears the
solution to this problem is the combination of coffimplib +
windows SDK. After using those on the SDK's oleaut32.lib I got a
library with the properly decorated _VarCmp@16.
Not your job, but this could probably be made simpler.