My project used and modified some code from project A licensed under GPLv2 written in C. Now I was wondering that if I release my compiled binary with its reverse-compiled assembly, is it GPLv2-conforming? It seems that reverse-compiled assembly is machine-readable and the definition of source code, "the preferred form of the work for making modifications", appears a little bit vague here.
If you were making modifications, would you prefer to work on the original source code, with proper structure, variable names, comments etc or on the decompiled version which may well be missing all of those? I know which I'd prefer, which I think answers this question.
Reverse-compiled assembly, made from object code compiled from C code that had been licensed under the GPLv2 and modified, is not source code under any reasonable definition. Distribution of such reverse-compiled assembly would not satisfy GPL terms that require distribution of source code.