Fix Windows build: define rand_r()

diff --git a/os/os-windows.h b/os/os-windows.h
index 159c086abaeb0182129181dd6a8bebe81ab0b402..d0495316b6e39c19772c5d4aad3252ad038ca382 100644 (file)
--- a/os/os-windows.h
+++ b/os/os-windows.h
@@ -20,6 +20,11 @@
 
 #include "windows/posix.h"
 
+/* Cygwin doesn't define rand_r if C99 or newer is being used */
+#if defined(WIN32) && !defined(rand_r)
+int rand_r(unsigned *);
+#endif
+
 #ifndef PTHREAD_STACK_MIN
 #define PTHREAD_STACK_MIN 65535
 #endif