LoadLibrary fails w/ Ruby 2.5 - Msys2

[whiting0]

I'm running Windows 10, with IBM MQ v9
I updated extconf.rb in order to point to the cmqc.h in the alternate path. The gem build and gem install are successful, but whey trying to use the gem I get

examples/request.rb:13:in `connect': WMQ::QueueManager#connect(). Failed to load MQ Library:mqm, rc=126 (WMQ::WMQException)

I can run amqsputc from the same command line, so I know that the directory for mqic.dll is in the path, but LoadLibrary() doesn't find/load the .dll

ruby 2.3.3 with the old devkit works
I tried installing the old devkit, but that didn't help. Is this a basic fault in msys2, or is there an issue with the compile/link?

[jake-007]

I can confirm this issue still exists. Older rubies with devkit (up to and including 2.3.x) compile the gem successfully, newer rubies (2.4-) with MSYS2 don't. I have tried both x86 and x64.

Windows Server 2016, IBM WebSphere MQ 7.5.