From 43afb1d4caad3fcf977883c4dad103bdda0a185c Mon Sep 17 00:00:00 2001
From: Ahmed Taei <ataei@fb.com>
Date: Tue, 20 Jun 2017 21:15:23 -0700
Subject: [PATCH] Make sure Elu alpha is strictly positive

Reviewed By: Yangqing

Differential Revision: D5289483

fbshipit-source-id: 96223304e4b1278595bae5ed137b5b80b7f8f521
---
 caffe2/operators/elu_op.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/caffe2/operators/elu_op.cc b/caffe2/operators/elu_op.cc
index b646b0bb3db4fb..db36584b52e84b 100644
--- a/caffe2/operators/elu_op.cc
+++ b/caffe2/operators/elu_op.cc
@@ -8,6 +8,8 @@ template <>
 bool EluOp<float, CPUContext>::RunOnDevice() {
   auto& X = Input(0);
   auto* Y = Output(0);
+  // Otherwise inplace gradient and Elu dosen't make sense.
+  CAFFE_ENFORCE_GE(alpha_, 0);
   Y->ResizeLike(X);
   const auto* Xdata = X.template data<float>();
   auto* Ydata = Y->template mutable_data<float>();