curl release package is a debug build

Brian Inglis
Mon Nov 30 23:59:43 GMT 2020

On 2020-11-29 20:17, Sara Angel via Cygwin wrote:
> curl release package being a debug build is causing it to fail on success
> in some cases.
> e.g.
> curl --cacert mycert.pem https://localhost:80
> curl: (56) OpenSSL SSL_read: Connection closed abruptly, errno 0 (Fatal
> because this is a curl debug build)
> The only thing related to this bug I could find is that msys2 had the same
> issue in their curl package

Raised issue upstream:

and got upstream response pointer to:
"For debug builds be a little stricter and error on any SSL_ERROR_SYSCALL.
For example a server may have closed the connection abruptly without a 
close_notify alert.

For compatibility with older peers we don't do this by default.

We can use this to gauge how many users may be affected, and if it goes ok 
eventually transition to allow in dev and release with the newest OpenSSL:
#if (OPENSSL_VERSION_NUMBER >= 0x10101000L)"

so will disable this in a new Cygwin release which will be uploaded soon.

*Curl users should be aware that deviations from strict protocol are deprecated 
and will be reported as errors unconditionally in a near future release.*

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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