Fix build with cmake flag BUILD_SHARED_LIBS=ON

Always build opencs-lib as static library instead of BUILD_SHARED_LIBS deciding
whether it's static or shared library.

.gitlab-ci.yml

@@ -210,6 +210,7 @@ Ubuntu_GCC_Debug:
     CCACHE_SIZE: 3G
     CMAKE_BUILD_TYPE: Debug
     CMAKE_CXX_FLAGS_DEBUG: -O0
+    BUILD_SHARED_LIBS: 1
   # When CCache doesn't exist (e.g. first build on a fork), build takes more than 1h, which is the default for forks.
   timeout: 2h
 

CI/before_script.linux.sh

@@ -22,7 +22,7 @@ declare -a CMAKE_CONF_OPTS=(
     -DCMAKE_C_COMPILER_LAUNCHER=ccache
     -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
     -DCMAKE_INSTALL_PREFIX=install
-    -DBUILD_SHARED_LIBS=OFF
+    -DBUILD_SHARED_LIBS="${BUILD_SHARED_LIBS:-OFF}"
     -DUSE_SYSTEM_TINYXML=ON
     -DOPENMW_USE_SYSTEM_RECASTNAVIGATION=ON
     -DOPENMW_CXX_FLAGS="-Werror -Werror=implicit-fallthrough"  # flags specific to OpenMW project

apps/opencs/CMakeLists.txt

@@ -172,7 +172,7 @@ else()
     set (OPENCS_OPENMW_CFG "")
 endif(APPLE)
 
-add_library(openmw-cs-lib
+add_library(openmw-cs-lib STATIC
     ${OPENCS_SRC}
     ${OPENCS_UI_HDR}
     ${OPENCS_MOC_SRC}