added cmake 3.7 as max cmake required version

[DvirDukhan]

following https://cmake.org/cmake/help/latest/command/cmake_minimum_required.html#command:cmake_minimum_required
we need to add version 3.5 as the optional max value

edit:
following PR discussion, I changed the max value from 3.5 to 3.7

[michael-grunder]

Not opposed to adding it but do we expect the build to break with higher versions? I can build just fine with 3.22.1.

[bjosv]

One thing to note is that CMake < 3.7 will not work when building with -DENABLE_SSL=ON

CMake Error at /opt/hostedtoolcache/cmake/3.6.0/x64/cmake-3.6.0-Linux-i386/share/cmake-3.6/Modules/FindOpenSSL.cmake:345 (list):
  list GET given empty list
Call Stack (most recent call first):
  CMakeLists.txt:159 (FIND_PACKAGE)

In libvalkey we set the minimum version to 3.7 which builds.
Using CMAKE_MINIMUM_REQUIRED(VERSION 3.0.0...3.7.0) could be an alternative.

[DvirDukhan]

@michael-grunder the problem is building the current code base with cmake 4. Building with Cmake 4 yields

CMake Error at CMakeLists.txt:1 (CMAKE_MINIMUM_REQUIRED):
  Compatibility with CMake < 3.5 has been removed from CMake.

  Update the VERSION argument <min> value.  Or, use the <min>...<max> syntax
  to tell CMake that the project requires at least <min> but has been updated
  to work with policies introduced by <max> or earlier.

  Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try configuring anyway.

[uglide]

@bjosv Are you sure it's not a build env problem on your side?

I've just tested with CMake 3.5 and 3.6 and it builds just fine:

$ cmake --version
cmake version 3.6.0

CMake suite maintained and supported by Kitware (kitware.com/cmake).

$ cmake -DENABLE_SSL=ON
Detected version: 1.2.0
-- The C compiler identification is GNU 9.4.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /playground/hiredis

#1292

[uglide]

I reproduced the problem with CMake 3.5 on GitHub Actions image and agree with @michael-grunder that we shouldn't limit the maximum version. I'm closing the PR now. For further discussion, please use #1292