Install External/OpenGL when building deprecated even without GL

Some deprecated APIs use headers (but not externally defined symbols)
from the GL library, link those includes as well


Signed-off-by: Squareys <squareys@googlemail.com>

src/Magnum/CMakeLists.txt

@@ -185,7 +185,9 @@ endif()
 target_include_directories(Magnum PUBLIC
     ${PROJECT_SOURCE_DIR}/src
     ${PROJECT_BINARY_DIR}/src)
-if(BUILD_DEPRECATED AND TARGET_GL) # TODO: remove once compat gets dropped
+if(BUILD_DEPRECATED) # TODO: remove once compat gets dropped
+    # Some deprecated APIs use headers (but not externally defined symbols)
+    # from the GL library, link those includes as well
     target_include_directories(Magnum PUBLIC
         ${PROJECT_SOURCE_DIR}/src/MagnumExternal/OpenGL)
 endif()
@@ -272,7 +274,7 @@ if(BUILD_TESTS)
     target_include_directories(MagnumTestLib PUBLIC
         ${PROJECT_SOURCE_DIR}/src
         ${PROJECT_BINARY_DIR}/src)
-    if(BUILD_DEPRECATED AND TARGET_GL) # TODO: remove once compat gets dropped
+    if(BUILD_DEPRECATED) # TODO: remove once compat gets dropped
         target_include_directories(MagnumTestLib PUBLIC
             ${PROJECT_SOURCE_DIR}/src/MagnumExternal/OpenGL)
     endif()

src/MagnumExternal/CMakeLists.txt

@@ -26,7 +26,10 @@
 if(WITH_AUDIO)
     add_subdirectory(OpenAL)
 endif()
-if(WITH_GL)
+# Some deprecated APIs use headers (but not externally defined symbols)
+# from the GL library, link those includes as well
+# TODO: remove once compat gets dropped
+if(WITH_GL OR MAGNUM_BUILD_DEPRECATED)
     add_subdirectory(OpenGL)
 endif()
 if(WITH_VK)

src/MagnumExternal/OpenGL/GL/CMakeLists.txt

@@ -23,6 +23,10 @@
 #   DEALINGS IN THE SOFTWARE.
 #
 
+# Some deprecated APIs use headers (but not externally defined symbols)
+# from the GL library, link those includes as well
+# TODO: remove once compat gets dropped (condition only)
+if(WITH_GL)
     # flextGLPlatform.cpp is compiled as part of Magnum*Context libraries in Platform
     add_library(MagnumFlextGLObjects OBJECT flextGL.cpp)
     target_include_directories(MagnumFlextGLObjects PUBLIC $<TARGET_PROPERTY:MagnumGL,INTERFACE_INCLUDE_DIRECTORIES>)
@@ -33,5 +37,6 @@ if(NOT BUILD_STATIC OR BUILD_STATIC_PIC)
         set_target_properties(MagnumFlextGLObjects PROPERTIES POSITION_INDEPENDENT_CODE ON)
     endif()
     set_target_properties(MagnumFlextGLObjects PROPERTIES FOLDER "MagnumExternal/OpenGL")
+endif()
 
 install(FILES flextGL.h DESTINATION ${MAGNUM_EXTERNAL_INCLUDE_INSTALL_DIR}/OpenGL/GL)