Add -Wtautological-undefined-compare and -Wundefined-bool-conversion warnings

to detect underfined behavior involving pointers.

llvm-svn: 210372

1 files changed, 37 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/warn-undefined-bool-conversion.cpp b/clang/test/SemaCXX/warn-undefined-bool-conversion.cpp
new file mode 100644
index 00000000000..c56b6bc1595
--- /dev/null
+++ b/clang/test/SemaCXX/warn-undefined-bool-conversion.cpp
@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fsyntax-only -verify -Wundefined-bool-conversion %s
+// RUN: %clang_cc1 -fsyntax-only -verify -Wno-bool-conversion -Wundefined-bool-conversion %s
+// RUN: %clang_cc1 -fsyntax-only -verify -Wbool-conversion %s
+
+void test1(int &x) {
+  if (x == 1) { }
+  if (&x) { }
+  // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed always converted to true}}
+
+  if (!&x) { }
+  // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed always converted to true}}
+}
+
+class test2 {
+  test2() : x(y) {}
+
+  void foo() {
+    if (this) { }
+    // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; pointer may be assumed always converted to true}}
+
+    if (!this) { }
+    // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; pointer may be assumed always converted to true}}
+  }
+
+  void bar() {
+    if (x == 1) { }
+    if (&x) { }
+    // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed always converted to true}}
+
+    if (!&x) { }
+    // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed always converted to true}}
+  }
+
+  int &x;
+  int y;
+};