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mapbox / mapnik-vector-tile

Mapnik implemention of Mapbox Vector Tile specification
BSD 3-Clause "New" or "Revised" License
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v2_spec warning: moving a temporary object prevents copy elision #174

Closed springmeyer closed 8 years ago

springmeyer commented 8 years ago

This is with clang++ 3.8

$ /opt/llvm/bin/clang++ -v
clang version 3.8.0 (http://llvm.org/git/clang.git c64147ff0ff60667f106dd47dae789f417f941e8) (http://llvm.org/git/llvm.git 30709900f394ba33d546b6830eadc7307add3219)
Target: x86_64-apple-darwin15.2.0
Thread model: posix
InstalledDir: /opt/llvm/bin

Seeing:

In file included from ../../src/vector_tile_processor.cpp:2:
../../src/vector_tile_processor.ipp:479:31: warning: moving a temporary object prevents copy elision [-Wpessimizing-move]
            lay_vec.push_back(std::move(std::async(
                              ^
../../src/vector_tile_processor.ipp:479:31: note: remove std::move call here
            lay_vec.push_back(std::move(std::async(
                              ^~~~~~~~~~
../../src/vector_tile_processor.ipp:500:31: warning: moving a temporary object prevents copy elision [-Wpessimizing-move]
            lay_vec.push_back(std::move(std::async(
                              ^
../../src/vector_tile_processor.ipp:500:31: note: remove std::move call here
            lay_vec.push_back(std::move(std::async(
                              ^~~~~~~~~~
2 warnings generated.