The MASM32 documentation clearly states that the GPL violates MASM32's license, and therefore cannot be applied to projects built with MASM32.The MASM32 project cannot be used to create open source software or any other project under any form of licence that requires the user of the MASM32 project to surrender the rights they are afforded under the MASM32 licence. In particular the MASM32 licence completely excludes projects licenced under the GNU organisation's published GPL licence and/or variants.However, no guidance is given on what licenses are MASM32 compatible.  My best guess based on the general push for freedom and not restriction in the MASM32 license is that the MIT license would be compatible.  However, I'm not a lawyer.  Anyone else gone down this path already and figured out which licenses are able to be used with MASM32?
What licenses are compatible with MASM32's license requirements?
licensing
Few, if any, open-source licenses are usable. I can pretty firmly say that the MIT/X11 license, the Apache license, all forms of the BSD license, the Creative Commons - Attribution licenses, and the Mozilla Public License are all incompatible with the statements of the MASM32 license as all require some kind of acknowledgement of origin or credit to someone as part of their terms.A little less firmly, I could say that use of MASM32 is basically incompatible with the Open Source Definition, as the tenets of the OSD include No Discrimination Against Fields of Endeavor (MASM32's idea of illegal software falls afoul of this) and License Must be Technology-Neutral (only write software for Windows falls afoul of this). This is a fuzzy, lawyer-requiring situation (I'm not one)  if your project is distributed under an OSD-compatible license, does the fact that MASM32's license prevents building it under certain situations void your license? Someone could in theory fork your code, remove the dependency on MASM32, and continue to distribute it under your license. I won't speculate.But in my opinion using MASM32, or encouraging its author by taking its ludicrous demands seriously, constitutes bad form, even if you think you can work around them.