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// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wextra -std=c++11
// RUN: %clang_cc1 %s -fsyntax-only -triple i686-unknown-unknown -verify -pedantic -Wextra -std=c++11
// RUN: %clang_cc1 %s -fsyntax-only -triple x86_64-unknown-unknown -verify -pedantic -Wextra -std=c++11
#include <stdint.h>
void f(intptr_t offset) {
// A zero offset from a nullptr is OK.
char *f = (char*)nullptr + 0;
int *g = (int*)0 + 0;
f = (char*)nullptr - 0;
g = (int*)nullptr - 0;
// adding other values is undefined.
f = (char*)nullptr + offset; // expected-warning {{arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension}}
// Cases that don't match the GNU inttoptr idiom get a different warning.
f = (char*)0 - offset; // expected-warning {{performing pointer arithmetic on a null pointer has undefined behavior if the offset is nonzero}}
g = (int*)0 + offset; // expected-warning {{performing pointer arithmetic on a null pointer has undefined behavior if the offset is nonzero}}
}
// Value-dependent pointer arithmetic should not produce a nullptr warning.
template<char *P>
char* g(intptr_t offset) {
return P + offset;
}
// Value-dependent offsets should not produce a nullptr warning.
template<intptr_t N>
char *h() {
return (char*)nullptr + N;
}
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