1 files changed, 41 insertions, 0 deletions
diff --git a/gcc/testsuite/g++.dg/opt/pr14029.C b/gcc/testsuite/g++.dg/opt/pr14029.C
new file mode 100644
index 000000000..1673edfd6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/pr14029.C
@@ -0,0 +1,41 @@
+// { dg-do run }
+// { dg-options "-O2" }
+// We used to mis-compile this testcase as we did not know that
+// &a+offsetof(b,a) was the same as &a.b
+
+struct Iterator {
+    int * ptr;
+
+    Iterator(int * i) : ptr(i) { }
+    void operator++() { ++ptr; }
+    int *const & base() const { return ptr; }
+};
+
+
+Iterator find_7(Iterator first, Iterator last)
+{
+  int trip_count  = (last.base() - first.base()) >> 1;
+
+  for ( ; trip_count > 0 ; --trip_count) {
+    if (*first.ptr == 7) return first;
+    ++first;
+
+    if (*first.ptr == 7) return first;
+    ++first;
+  }
+
+  switch(last.base() - first.base()) {
+    case 1:
+          if (*first.ptr == 7) return first;
+          ++first;
+    case 0:
+    default:
+          return last;
+  }
+}
+
+int main() {
+  int as[5] = {4,4,4,4,7};
+  return (find_7(Iterator(&as[0]), Iterator(&as[5])).ptr == &as[5]);
+};
+