Android and CONAN_LIBCXX do not play well together

[theodelrieu]

Hello,

After #2049, I went to every recipe to use one of the following fixes:

if self.settings.os == "Android":
    cmake.definitions["CONAN_LIBCXX"] = ""

del self.settings.compiler.libcxx

It would be great if Conan could set that automatically, I believe this is an issue when using the standalone android toolchain, from what I recall from the chat on Slack I had with @memsharded

I'm using Conan 1.0.4 on macOS 10.13

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[lasote]

I'm not sure if we should remove it always, I read about it and the NDK people are changing many things lately regarding the clang/libcxx integration as the only choice. Probably in future NDK versions the libcxx flag won't error.

However, I agree we should document it. So I'm opening an issue in the docs repository.

[theodelrieu]

I agree that we shall wait the r17 release, where clang will be the only choice.

In my android-toolchain recipe, I'm not setting self.cpp_info.libdirs, only the sysroot.
But it seems that having the -lc++ flag without -L breaks.

Moreover, in my case I'm linking against the static C++ libs, which have different name.
I should find a way to set CONAN_LICBXX="" in the toolchain directly.

[JamesWeir]

I added a comment to #2049, which may be of interest and is to do with what make standalone toolchain does in the android ndk package, specifically copying libc++ over libstdc++ to make it look like libstdc++ from external tools perspective and it makes everything confused.

[memsharded]

the new CMakeToolchain should handle this now