Fix empty vector argument array construction - #218
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kalvdans
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| if (n > 0) | ||
| heap.copy<T>(a,aa.data(),n); |
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Nit: aa.data() is fine to call on an empty std::vector (might or might not return nullptr). do we need the if (n > 0) then?
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Good point, and thanks for noting that. I still decided to keep the redundant if, as it shouldn't cost anything at runtime, and I like that it is explicit and not relying on API promises.
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The canonical way is
if (!aa.empty())
heap.copy<T>(a,aa.data(),n);
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Summary
std::vectorinstances by avoiding&aa[0]when the vector is empty.IntArgs,IntVarArgs, andBoolVarArgs.Fixes #205.
Validation
cmake -S . -B /tmp/gecode-empty-vector-args-build -DCMAKE_BUILD_TYPE=Debug -DGECODE_ENABLE_EXAMPLES=OFF -DGECODE_ENABLE_GIST=OFF -DGECODE_ENABLE_QT=OFFcmake --build /tmp/gecode-empty-vector-args-build --target gecode-test -j 8/tmp/gecode-empty-vector-args-build/bin/gecode-test -test Array::Vector::Emptygit diff --check