OK Tim. Thanks for your concern.
Why the double quotes ? It is pointed by the linker. So probably I should not use it as a linking option, though the MySQL command line
yields that string. I also tried not to use it, and I got many more errors. I just installed Code::Blocks. Now, if, as it seems to me, nobody here had attempted a cross-compilation of a C++ source code to produce a Windows executable able to connect to MySQL, I do not have the time to investigate nor, perhaps, the knowledge of how this thing was written, what are the messages, why are those switches rejected. Maybe the explanation is available. Maybe, it is not. What does the error means ? Well, maybe this will help the C::B developers to explain more clear where to put the things, or why are they "rejected" when they are placed in the "assumed" right place. As I see the things, if C:B does not solve my problem -and it seems it does not- I need to carry on. As said, no time to investigate, not exactly around C::B, maybe I will turn to the compiler, which is a cross-compiler, that does not find the libraries it has to link. So my problem is no C:B-related, my problem is of some other kind, maybe, I need other switches, because I can compile an ELF Linux binary that runs perfectly well, and a Windows binary that runs perfectly well, but not a Windows binary that connects to MySQL. I see I have a problem at linking stage, but I don't know how to solve it. So I should look somewhere else.
Thanks for your concern.