diff --git a/src/lib/syscall.c b/src/lib/syscall.c
index 0edd460..d520c0a 100644
--- a/src/lib/syscall.c
+++ b/src/lib/syscall.c
@@ -17,6 +17,8 @@
 
 #include <assert.h>
 #include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
 
 #include <common/log.h>
 
@@ -112,6 +114,19 @@ LIBC_SYSCALL_DECL
 	LIBC_SYSCALL_RET_TYPE ret;
 	va_list args;
 
+#if defined(SYS_mmap) || defined(SYS_mmap2)
+	if (NULL == tsocks_libc_syscall) {
+		switch (__number) {
+		case SYS_mmap:
+#ifdef SYS_mmap2
+		case SYS_mmap2:
+#endif
+			fprintf(stderr, "Panic! mmap has been called before we had our hands on the real syscall()\n");
+			exit(EXIT_FAILURE);
+			break;
+		}
+	}
+#endif
 	/* Find symbol if not already set. Exit if not found. */
 	tsocks_libc_syscall = tsocks_find_libc_symbol(LIBC_SYSCALL_NAME_STR,
 			TSOCKS_SYM_EXIT_NOT_FOUND);