llvm-project/clang/test/Lexer/cxx0x_raw_string_delim_length.cpp

// RUN: %clang_cc1 -std=c++11 -E %s 2>&1 | grep 'error: raw string delimiter longer than 16 characters'

const char *str = R"abcdefghijkmnopqrstuvwxyz(abcdef)abcdefghijkmnopqrstuvwxyz";