llvm-project/clang/test/Sema/pointer-subtraction.cpp

20 lines
1.0 KiB
C++

// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wextra -std=c++11 -isystem %S/Inputs
// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wnull-pointer-subtraction -std=c++11 -isystem %S/Inputs
// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wextra -std=c++11 -isystem %S/Inputs -Wsystem-headers -DSYSTEM_WARNINGS
// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wnull-pointer-subtraction -std=c++11 -isystem %S/Inputs -Wsystem-headers -DSYSTEM_WARNINGS
#include <pointer-subtraction.h>
void a() {
char *f = (char *)0;
f = (char *)((char *)0 - f); // expected-warning {{performing pointer subtraction with a null pointer may have undefined behavior}}
f = (char *)(f - (char *)0); // expected-warning {{performing pointer subtraction with a null pointer may have undefined behavior}}
f = (char *)((char *)0 - (char *)0); // valid in C++
#ifndef SYSTEM_WARNINGS
SYSTEM_MACRO(f);
#else
SYSTEM_MACRO(f); // expected-warning {{performing pointer subtraction with a null pointer may have undefined behavior}}
#endif
}