Description:
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When calling the enable argument of stream_socket_enable_crypto is true, I the crypto type argument is not really optional, as the documentation suggests.

So, I supposed if you call stream_socket_enable_crypto with enable argument true and omit crypto_type, it would assume you want to enable client SSL/TLS negotiation, but instead PHP crashes.

Reproduce code:
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stream_socket_enable_crypto($socket, true);

Expected result:
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Fail warning the user that the crypto_type must be specified.

Actual result:
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Segmentation fault .,