The documentation in msvc32.mak explains to define WIN32 or WIN64 to build the corresponding target; however it uses this information not only in building the target, but in locating the compiler on the build system.

So when building the 32-bit configuration on a 64-bit system in VS9 for example, line 473 of msvc.mak sets the DEVSTUDIO path to where one would expect to find it on a 32-bit machine, resulting in a failed build because the compiler cannot be found.

Workaround: Change the path as required.

Fix: Do not use WIN32 or WIN64 in determining the DEVSTUDIO path.