Threading support in mingw win32 builds

Makefile

@@ -26,10 +26,12 @@ ifndef KRK_ENABLE_STATIC
   else
     # For Windows, disable format string warnings because gcc will get mad
     # about non-portable Windows format specifiers...
-    CFLAGS  += -Wno-format
+    CFLAGS  += -Wno-format -static-libgcc
     # And we need to link this by name with extension because I don't want
     # to actually rename it to kuroko.dll or whatever.
     MODLIBS = libkuroko.so
+    LDLIBS += -l:libwinpthread.a
+    ${OBJS}: CFLAGS += -DKRKINLIB
   endif
   all: ${TARGET} ${MODULES} ${TOOLS}
   KUROKO_LIBS = libkuroko.so

src/kuroko.h

@@ -17,6 +17,7 @@ typedef long long krk_integer_type;
 # define PRIkrk_int "%I64d"
 # define PRIkrk_hex "%I64x"
 # define parseStrInt strtoll
+# define ENABLE_THREADING
 # else
 typedef long krk_integer_type;
 # define PRIkrk_int "%ld"

src/threads.h

@@ -7,6 +7,13 @@
 #ifdef ENABLE_THREADING
 #include <pthread.h>
 #include <sched.h>
+
+#ifdef _WIN32
+#include <windows.h>
+#include <winnt.h>
+#define sched_yield() YieldProcessor()
+#endif
+
 static inline void _krk_internal_spin_lock(int volatile * lock) {
 	while(__sync_lock_test_and_set(lock, 0x01)) {
 		sched_yield();

src/vm.h

@@ -243,7 +243,11 @@ typedef struct KrkVM {
  *
  * See @c KrkThreadState for more information.
  */
+#if defined(_WIN32) && !defined(KRKINLIB)
+#define krk_currentThread (*krk_getCurrentThread())
+#else
 extern threadLocal KrkThreadState krk_currentThread;
+#endif
 
 /**
  * @brief Singleton instance of the shared VM state.