31 lines · cpp
1// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wextra -std=c++112// RUN: %clang_cc1 %s -fsyntax-only -triple i686-unknown-unknown -verify -pedantic -Wextra -std=c++113// RUN: %clang_cc1 %s -fsyntax-only -triple x86_64-unknown-unknown -verify -pedantic -Wextra -std=c++114 5#include <stdint.h>6 7void f(intptr_t offset) {8 // A zero offset from a nullptr is OK.9 char *f = (char*)nullptr + 0;10 int *g = (int*)0 + 0;11 f = (char*)nullptr - 0;12 g = (int*)nullptr - 0;13 // adding other values is undefined.14 f = (char*)nullptr + offset; // expected-warning {{arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension}}15 // Cases that don't match the GNU inttoptr idiom get a different warning.16 f = (char*)0 - offset; // expected-warning {{performing pointer arithmetic on a null pointer has undefined behavior if the offset is nonzero}}17 g = (int*)0 + offset; // expected-warning {{performing pointer arithmetic on a null pointer has undefined behavior if the offset is nonzero}}18}19 20// Value-dependent pointer arithmetic should not produce a nullptr warning.21template<char *P>22char* g(intptr_t offset) {23 return P + offset;24}25 26// Value-dependent offsets should not produce a nullptr warning.27template<intptr_t N>28char *h() {29 return (char*)nullptr + N;30}31