THRIFT-5208: capitalize exception ctor
diff --git a/compiler/cpp/src/thrift/generate/t_ocaml_generator.cc b/compiler/cpp/src/thrift/generate/t_ocaml_generator.cc
index 300b5ac..5e86de4 100644
--- a/compiler/cpp/src/thrift/generate/t_ocaml_generator.cc
+++ b/compiler/cpp/src/thrift/generate/t_ocaml_generator.cc
@@ -1665,7 +1665,7 @@
   }
 
   string name = ttype->get_name();
-  if (ttype->is_service()) {
+  if (ttype->is_service() || ttype->is_xception()) {
     name = capitalize(name);
   } else {
     name = decapitalize(name);