finalizers.c: In function 'start_finalization_thread':
finalizers.c:259:7: error: wrong type argument to unary exclamation mark
finalizers.c: In function 'stop_finalization_thread':
finalizers.c:274:7: error: used struct type value where scalar is required
finalizers.c:279:27: error: incompatible types when assigning to type 'pthread_t' from type 'int'
here, the problem is that the code uses a non-portable feature of linux pthreads, namely that pthread_t is implemented as an arithmetic type.
The manual page for pthread_self(3) states:
"POSIX.1 allows an implementation wide freedom in choosing the type used to represent a thread ID; for example, representation using either an arithmetic type or a structure is permitted. Therefore, variables of type pthread_t can't portably be compared using the C equality operator (==); use pthread_equal(3) instead."
Mingw pthreads do make use of that freedom, and define pthread_t as a struct, hence the code fails to compile.
As I browsed through bug-guile, and it seems to be a recurring issue, and usually the proposed solution is to compile guile without threads, which is not acceptable in my case.