1 files changed, 76 insertions, 0 deletions
diff --git a/clang/test/Analysis/null-pointer-arithm.c b/clang/test/Analysis/null-pointer-arithm.c
new file mode 100644
index 0000000..2288247
--- /dev/null
+++ b/clang/test/Analysis/null-pointer-arithm.c
@@ -0,0 +1,76 @@
+// RUN: %clang_analyze_cc1 -verify %s \
+// RUN:   -analyzer-checker=core
+
+extern int *get_pointer();
+
+int *test_add1(int offset) {
+  int *p = get_pointer();
+  if (p) {}
+  return p + offset; // expected-warning{{Addition of a null pointer (from variable 'p') and a probably nonzero integer value (from variable 'offset') may result in undefined behavior}}
+}
+
+int *test_add2(int offset) {
+  int *p = get_pointer();
+  if (p) {}
+  if (offset) {}
+  return p + offset; // expected-warning{{Addition of a null pointer (from variable 'p') and a nonzero integer value (from variable 'offset') results in undefined behavior}}
+}
+
+int *test_add3(int offset) {
+  int *p = get_pointer();
+  if (p) {}
+  if (offset != 0) return 0;
+  return p + offset;
+}
+
+int *test_add4(int offset) {
+  int *p = get_pointer();
+  if (p) {}
+  if (offset == 0) return 0;
+  return p + offset; // expected-warning{{Addition of a null pointer (from variable 'p') and a nonzero integer value (from variable 'offset') results in undefined behavior}}
+}
+
+int *test_add5(int offset) {
+  int *p = get_pointer();
+  if (p) {}
+  return offset + p; // expected-warning{{Addition of a probably nonzero integer value (from variable 'offset') and a null pointer (from variable 'p') may result in undefined behavior}}
+}
+
+int *test_sub1(int offset) {
+  int *p = get_pointer();
+  if (p) {}
+  return p - offset; // expected-warning{{Subtraction of a null pointer (from variable 'p') and a probably nonzero integer value (from variable 'offset') may result in undefined behavior}}
+}
+
+int test_sub_p1() {
+  int *p = get_pointer();
+  if (p) {}
+  return p - p;
+}
+
+int test_sub_p2() {
+  int *p1 = get_pointer();
+  int *p2 = get_pointer();
+  if (p1) {}
+  if (p2) {}
+  return p1 - p2;
+  // expected-warning@-1{{Subtraction of a non-null pointer (from variable 'p1') and a null pointer (from variable 'p2') results in undefined behavior}}
+  // expected-warning@-2{{Subtraction of a null pointer (from variable 'p1') and a non-null pointer (from variable 'p2') results in undefined behavior}}
+}
+
+int test_sub_p3() {
+  int *p1 = get_pointer();
+  int *p2 = get_pointer();
+  if (p1) {}
+  return p1 - p2; // expected-warning{{Subtraction of a null pointer (from variable 'p1') and a probably non-null pointer (from variable 'p2') may result in undefined behavior}}
+}
+
+struct S {
+  char *p;
+  int offset;
+};
+
+char *test_struct(struct S s) {
+  if (s.p) {}
+  return s.p + s.offset; // expected-warning{{Addition of a null pointer (via field 'p') and a probably nonzero integer value (via field 'offset') may result in undefined behavior}}
+}