Fix more -Wshorten-64-to-32 warnings.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50659 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Unix/Signals.inc b/lib/System/Unix/Signals.inc
index 3314a43..79236cd 100644
--- a/lib/System/Unix/Signals.inc
+++ b/lib/System/Unix/Signals.inc
@@ -65,7 +65,8 @@
 static void PrintStackTrace() {
 #ifdef HAVE_BACKTRACE
   // Use backtrace() to output a backtrace on Linux systems with glibc.
-  int depth = backtrace(StackTrace, array_lengthof(StackTrace));
+  int depth = backtrace(StackTrace,
+                        static_cast<int>(array_lengthof(StackTrace)));
   backtrace_symbols_fd(StackTrace, depth, STDERR_FILENO);
 #endif
 }