[PATCH] Fix -fsanitize=vptr sanopt lowering (PR sanitizer/65004)

[Richard Biener]

On February 10, 2015 9:08:33 PM CET, Jakub Jelinek <jakub@redhat.com> wrote:
>Hi!
>
>As ubsan_expand_vptr_ifn points *gsip to the first stmt in the next bb,
>we want to always return true as no_next, we never want to gsi_next on
>it
>before processing it further, otherwise we could skip some important
>statement (e.g. another UBSAN_* call).
>
>Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok
>for
>trunk?

Ok.

Thanks,
Richard.

>2015-02-10  Jakub Jelinek  <jakub@redhat.com>
>
>	PR sanitizer/65004
>	* ubsan.c (ubsan_expand_vptr_ifn): Always return true.
>
>	* g++.dg/asan/pr65004.C: New test.
>
>--- gcc/ubsan.c.jj	2015-01-28 08:39:53.000000000 +0100
>+++ gcc/ubsan.c	2015-02-10 18:44:59.796872508 +0100
>@@ -1148,7 +1148,7 @@ ubsan_expand_vptr_ifn (gimple_stmt_itera
>   /* Get rid of the UBSAN_VPTR call from the IR.  */
>   unlink_stmt_vdef (stmt);
>   gsi_remove (&gsi, true);
>-  return gsi_end_p (*gsip);
>+  return true;
> }
> 
>/* Instrument a memory reference.  BASE is the base of MEM, IS_LHS says
>--- gcc/testsuite/g++.dg/asan/pr65004.C.jj	2015-02-10
>18:49:48.521988574 +0100
>+++ gcc/testsuite/g++.dg/asan/pr65004.C	2015-02-10 18:51:22.249407985
>+0100
>@@ -0,0 +1,48 @@
>+// PR sanitizer/65004
>+// { dg-do compile }
>+// { dg-options "-fcompare-debug -fsanitize=address
>-fsanitize=undefined -fno-sanitize-recover=all" }
>+
>+namespace N {
>+  template <typename Signature> struct function;
>+  namespace detail {
>+    namespace function {
>+      struct vtable_base { };
>+    }
>+  }
>+  struct function_base {
>+    detail::function::vtable_base * vtable;
>+  };
>+  template <typename R, typename T0> struct function1 : public
>function_base { };
>+  template <typename R, typename T0> struct function <R (T0)> : public
>function1 <R, T0> { };
>+}
>+namespace Bar {
>+  typedef N::function <void (const char *)> WarningHandler;
>+}
>+namespace Foo {
>+  struct FooRecord {
>+    virtual ~FooRecord ();
>+  };
>+  struct TestRecord : public FooRecord {
>+    long x;
>+  };
>+}
>+namespace Foo {
>+  using Bar::WarningHandler;
>+  struct FooScanner {
>+    WarningHandler warnHandler;
>+    int readByte ();
>+    long readSignedInteger ();
>+  };
>+  struct FooRecordReader {
>+    FooScanner & scanner;
>+    long readSInt ();
>+    void readTestRecord (TestRecord * recp);
>+  };
>+  inline long FooRecordReader::readSInt () {
>+    return scanner.readSignedInteger ();
>+  }
>+  void FooRecordReader::readTestRecord (TestRecord * recp) {
>+    int infoByte = scanner.readByte ();
>+    recp->x = readSInt ();
>+  }
>+}
>
>	Jakub