Unexpected result when using type_erased adaptor to a transformed_range when clang optimizations are enabled

[Alfredo Altamirano <fredy.altamirano8@…>]

If clang optimizations -O1 are enabled, when using type_erased adapter on a transformed_range, the range will yield wrong values.

For example:

int addOne(int b) {

return b + 1;

}

int main() {

std::vector<int> nums{ 1, 2, 3 }; auto result = nums | boost::adaptor::transformed(addOne) | boost::adaptor::type_erased<int, boost::forward_traversal_tag>();

}

When printing result, it yielded { 1, 1, 1 } instead of { 2, 3, 4 } when compiling with -O1. It worked as expected with no optimization flags. I am compiling the code with clang++. The version of clang is Apple LLVM version 8.0.0 (clang-800.0.38). And I am using c++11.

​http://stackoverflow.com/questions/40479397/getting-unexpected-result-when-compiling-with-clang-optimization?noredirect=1#comment68203492_40479397

[Alfredo Altamirano <fredy.altamirano8@…>]

C++ code reproducing the code.