OpenSceneGraph build against libstdc++ (should be libc++)

[hartmut@…]

Seems OpenSceneGraph is being built with gcc or for some other reason linked against libstdc++

otool against libosg.dylib reveals:

Load command 13
          cmd LC_LOAD_DYLIB
      cmdsize 56
         name /usr/lib/libstdc++.6.dylib (offset 24)

Hence, mixing with other libraries (such as OpenCV) is not possible. This is on Mavericks without any modifications (fresh MacPorts install).

[ryandesign (Ryan Carsten Schmidt)]

I do see the line in CMakeLists.txt that says:

            set(CMAKE_XCODE_ATTRIBUTE_CLANG_CXX_LIBRARY "libstdc++")

So I can see why that would be the case.

Nevertheless, when building on 10.10, it gets built with libc++. I'm not sure how.

[hartmut@…]

Oh, I see. I would guess its worthwhile to report this upstream? Thoughts?

[mamoll (Mark Moll)]

If I comment out these lines everything still compiles fine:

set(CMAKE_XCODE_ATTRIBUTE_CLANG_CXX_LANGUAGE_STANDARD "c++98")
set(CMAKE_XCODE_ATTRIBUTE_CLANG_CXX_LIBRARY "libstdc++")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++98 -stdlib=libstdc++ -Wno-overloaded-virtual -Wno-conversion")

Is there any downside to this? With the port as it is now, I'm having some trouble compiling some other code that depends on OpenSceneGraph and various other libraries. Somehow, linking against both libstdc++ and libc++ doesn't seem to work well.

[MarcusCalhoun-Lopez (Marcus Calhoun-Lopez)]

In 98a6d96874a4c0f194b95f2aaacf1fe54367c038/macports-ports (master):

OpenSceneGraph: respect MacPorts compiler flags

Fixes #45287