mingw32 compile error: transaction.c:12:10: fatal error: .\..._p.h: No such file or directory
Compiling gwenhyfar for mingw32|mingw64 (see https://build.opensuse.org/package/show/home:rhabacker:branches:windows:mingw:win64:snapshots/mingw64-gwenhywfar5) fails with the mentioned error. The appended patch fixes that issue.
But shouldn't include-paths inside a C source code file use the forward slash anyway as dir separator? Apparently the C standard deliberately doesn't say anything about file system paths or a directory separator character; there is some discussion here https://stackoverflow.com/questions/5790161/is-the-backslash-acceptable-in-c-and-c-include-directives
Conclusion there: Better stick with forward-slashes anyway, except for some very old MSVC compilers, which gwen doesn't support anyway.
So the better solution is to change the gwen typemaker code to NOT use GWEN_DIR_SEPARATOR_S for paths that are used in the `#include` preprocessor directives but instead directly use "/" there.