Made thread test work on Windows.

test cases/common/102 threads/threadprog.cpp

@@ -1,3 +1,30 @@
+/* On Windows not all versions of VS support C++11 and
+ * some (most?) versions of mingw don't support std::thread,
+ * even though they do support c++11. Since we only care about
+ * threads working, do the test with raw win threads.
+ */
+
+#if defined _WIN32
+
+#include<windows.h>
+#include<stdio.h>
+
+DWORD WINAPI thread_func(LPVOID) {
+    printf("Printing from a thread.\n");
+    return 0;
+}
+
+int main(int, char**) {
+    printf("Starting thread.\n");
+    HANDLE th;
+    DWORD id;
+    th = CreateThread(NULL, 0, thread_func, NULL, 0, &id);
+    WaitForSingleObject(th, INFINITE);
+    printf("Stopped thread.\n");
+    return 0;
+}
+#else
+
 #include<thread>
 #include<cstdio>
 
@@ -12,3 +39,5 @@ int main(int, char**) {
     printf("Stopped thread.\n");
     return 0;
 }
+
+#endif