1 files changed, 30 insertions, 0 deletions
diff --git a/test/SemaCXX/nullptr-arithmetic.cpp b/test/SemaCXX/nullptr-arithmetic.cpp
new file mode 100644
index 0000000000000..9963c8858ee87
--- /dev/null
+++ b/test/SemaCXX/nullptr-arithmetic.cpp
@@ -0,0 +1,30 @@
+// 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;
+}