C++
clang HEAD 12.0.0 (https://github.com/llvm/llvm-project.git 035396197a5f129c5ec42e9e46a85c32fa1c1b84)
$ clang++ prog.cc -Wall -Wextra -I/opt/wandbox/boost-1.73.0/clang-head/include -std=c++2a prog.cc:8:6: error: explicit instantiation of 'max' does not refer to a function template, variable template, member function, member class, or static data member
void max(const int &, const int &); // C4667 expected
^
prog.cc:4:10: note: candidate template ignored: could not match 'const type-parameter-0-0 &' against 'void'
const T &max(const T &a, const T &b) {
^
1 error generated.