Fix a few warnings/errors for compiling with -fno-exceptions.

llvm-svn: 178267
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: e00e6f23d36a802c7a81876891e4b470513d9cae
diff --git a/src/locale.cpp b/src/locale.cpp
index b7a4784..90bc77c 100644
--- a/src/locale.cpp
+++ b/src/locale.cpp
@@ -6003,6 +6003,8 @@
 {
 #ifndef _LIBCPP_NO_EXCEPTIONS
     throw runtime_error(msg);
+#else
+    (void)msg;
 #endif
 }