When creating a makefile project using VS2005 that wraps a call to nmake, it seems that Visual Studio always thinks that it's out-of-date and attempts to build it. I've tried explicitly setting the output filename (in project settings, NMake, Output) but this doesn't have any effect.
I have a test case that simply contains a project with a makefile that does a file copy, and you can see that VS always invokes nmake, even if the file is up-to-date. Let me know if you want it.
It's not clear to me how VS infers what the output file should be compared against Am I missing something
Btw, the behaviour is the same in VS2005 and SP1.