terraform getting stuck when remote-exec inline is empty

gistfile1.txt

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aws_instance.main (remote-exec): Connecting to remote host via SSH...
2017/03/24 19:05:17 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:17 connecting to TCP connection for SSH
aws_instance.main (remote-exec):   Host: x.y.z.a
aws_instance.main (remote-exec):   User: centos
aws_instance.main (remote-exec):   Password: false
aws_instance.main (remote-exec):   Private key: false
aws_instance.main (remote-exec):   SSH Agent: true
2017/03/24 19:05:17 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:17 handshaking with SSH
aws_instance.main: Still creating... (50s elapsed)
2017/03/24 19:05:18 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:18 [DEBUG] Telling SSH config to forward to agent
2017/03/24 19:05:18 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:18 [DEBUG] Setting up a session to request agent forwarding
2017/03/24 19:05:18 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:18 opening new ssh session
2017/03/24 19:05:18 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:18 [INFO] agent forwarding enabled
aws_instance.main (remote-exec): Connected!
2017/03/24 19:05:18 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:18 Retryable error: Failed to upload script: Error reading script: EOF
2017/03/24 19:05:21 [DEBUG] vertex "meta.count-boundary (count boundary fixup)", waiting for: "output.public_ip"
2017/03/24 19:05:21 [DEBUG] vertex "output.public_ip", waiting for: "aws_eip.main_instance"
2017/03/24 19:05:21 [DEBUG] vertex "aws_eip.main_instance", waiting for: "aws_instance.main"
2017/03/24 19:05:21 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:21 Retryable error: Failed to upload script: Error reading script: EOF
2017/03/24 19:05:24 [DEBUG] plugin: terraform-0.8.8: remote-exec-provisioner (internal) 2017/03/24 19:05:24 Retryable error: Failed to upload script: Error reading script: EOF

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