[CMake] Linker error when building 3.8.0-rc4 on Linux

[Nils Gladitz]

On 03/31/2017 11:54 AM, Alan W. Irwin wrote:

> Hi Nils:
>
> And use of ExternalProject_Add, etc.  In other words, this is a pretty
> crippling restriction for users with Linux distributions (such as the
> quite recent Ubuntu 2016.10 of the original poster) that do not yet
> give access to libssl version 1.1.0 (the oldest version of libssl
> where HMAC_CTX_new() and HMAC_CTX_free() are available according to
> your previous post).

Strangely enough I have no issue on Ubuntu 16.04 with the system default 
installation of OpenSSL.

What I missed in the original post is that the error comes from 
libarchive rather than libcurl.
But libarchive itself also seems to provide inline definitions of the 
missing functions in 
Utilities/cmlibarchive/libarchive/archive_openssl_hmac_private.h for 
OpenSSL < 1.1.

I can't tell why the inline definitions aren't used on the original 
posters system.
Perhaps there is a mismatch between OpenSSL headers and libraries?


Nils