llvm-project/clang/test/Preprocessor/cxx_oper_keyword.cpp

// RUN: %clang_cc1 %s -E -verify -DOPERATOR_NAMES
// RUN: %clang_cc1 %s -E -verify -fno-operator-names

#ifndef OPERATOR_NAMES
//expected-error@+3 {{token is not a valid binary operator in a preprocessor subexpression}}
#endif
// Valid because 'and' is a spelling of '&&'
#if defined foo and bar
#endif

// Not valid in C++ unless -fno-operator-names is passed:

#ifdef OPERATOR_NAMES
//expected-error@+2 {{C++ operator 'and' (aka '&&') used as a macro name}}
#endif
#define and foo

#ifdef OPERATOR_NAMES
//expected-error@+2 {{C++ operator 'xor' (aka '^') used as a macro name}}
#endif
#if defined xor
#endif

// For error recovery we continue as though the identifier was a macro name regardless of -fno-operator-names.
#ifdef OPERATOR_NAMES
//expected-error@+3 {{C++ operator 'and' (aka '&&') used as a macro name}}
#endif
//expected-warning@+2 {{and is defined}}
#ifdef and
#warning and is defined
#endif