Trying to compile with NDK R22 fails about fruit HOT 11 CLOSED

Hi, can you please post the full log from the cmake command and any other commands you ran? In case there's more interesting info.
Please also attach the generated CMakeCache.txt.

The fact that a plain #include <iostream> doesn't work suggests an issue with the setup, not really specific to Fruit. You can probably repro the same issue building a hello world program (with cmake).

You're already overriding the compiler locations, maybe you also need some flags to override the standard library locations?
Or maybe you installed the clang binaries but not the standard library headers?

from fruit.

I also found this:
opencv/opencv#8742 (comment)

Maybe you need similar cmake flags? Notably the tool chain override.

from fruit.

Appreciate the fast response :)
The entire CMake log and CMakeCache is here.
I will be attempting the toolchain override soon to see if that improves.

from fruit.

This is a log attempting to use the Android toolchain override.
https://gist.github.com/Fernthedev/d89c5f1d8797406af0411b4b1f7d479c

To clarify, I've used theses flags on another project being mimalloc with success, I'm not sure how Fruit differs to it however.

from fruit.

There are warnings that the build may be incomplete due to clock skew.
Maybe delete the build dir and try from scratch to see if it's different?
Make uses timestamps to decide what to rebuild so otherwise it may not be building everything it should.

You might also want to try using -DFRUIT_TESTS_USE_PRECOMPILED_HEADERS=OFF in case it's just the PCH compilation failing.

mimalloc seems to be a C library so the fact that it builds doesn't say much on whether the C++ STL is installed correctly and the C++-related cmake flags are correct.

You can also run make in verbose mode, as make VERBOSE=1 to see the exact command that is failing (that you can then run on its own manually playing around with flags to see if sth helps).
Btw, what make command are you running? Just make with no arguments or sth else?

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-DFRUIT_TESTS_USE_PRECOMPILED_HEADERS=OFF fixes it however I'm not sure if that guarantees it will work. Every build run has been with a completely new cache (I've essentially just removed all changed/added files using git)

I was running make -j which you can see at the end of my long CMake build command.

from fruit.

Would you mind telling me where the built files would be? Checking out/release it doesn't seem to have any .a or .so files 🤔

from fruit.

Oh great then it should be ok.
Pre compiled headers are a bit of an advanced feature, i guess they don't work well with cross compilation.

You can do make install DESTDIR=/some/dir to install the built fruit there.

Iirc the lib in the build tree ends up in src, but it's better to use make install than hunting down the various built pieces manually.

from fruit.

Alright I found it in the src folder. Thank you very much for your help and I'll be closing the issue as it seems (for now) to be building correctly.

Have a good day :)

from fruit.

Great!
Can you please post the final working command here in case someone else needs to do this in the future?

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export CC=$ANDROID_NDK_ROOT/toolchains/llvm/prebuilt/linux-x86_64/bin/clang
export CXX=$ANDROID_NDK_ROOT/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++
cmake . -DCMAKE_BUILD_TYPE=Release -DFRUIT_USES_BOOST=False -DCMAKE_SYSTEM_NAME=Android -DCMAKE_ANDROID_API=24 -DCMAKE_ANDROID_ARCH_ABI=arm64-v8a -DCMAKE_ANDROID_NDK=$ANDROID_NDK_ROOT -DCMAKE_ANDROID_STL_TYPE=c++_static -DCXX_STANDARD=20 -DCMAKE_TOOLCHAIN_FILE=$ANDROID_NDK_ROOT/build/cmake/android.toolchain.cmake -DANDROID_TOOLCHAIN=clang -DFRUIT_TESTS_USE_PRECOMPILED_HEADERS=OFF && make -j

seems to work nicely. I'll be trying linking in a while though so I may come back to this at a later date.

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