Merge branch 'Suppress_warnings-GF' into 'master'

Suppress warnings concerning gmm.h and perform some static_cast

See merge request !35
6 jobs for master in 8 minutes and 41 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #60471
Qt551 VS2013
CoMISo-VS2013-Qt-5.5.1-x64

00:01:13

passed #60472
IPOPT3129 VS2017
CoMISo-VS2017-Qt-5.10.1-x64

00:01:25

passed #60469
Linux
clang-c++11

00:07:26

passed #60468
Linux
gcc-c++11

00:04:22

passed #60470
Apple
macos-c++11

00:02:47

 
  Deploy
passed #60473
trigger_build

00:00:01