Fix for PR39557

From-SVN: r145119

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3b91d915a9f7aec597cba4f56da072f11560b02e..9ca01a2b653ec1c32d8eae84922ae2db58482234 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2009-03-27  Xinliang David Li  <davidxl@google.com>
+
+       PR tree-optimization/39557
+       * tree-ssa.c (warn_uninitialized_vars): free postdom info.
+
 2009-03-27  Xinliang David Li  <davidxl@google.com>
 
        PR tree-optimization/39548

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4b64a988f6392b1a599317f07c0936bb7fcba160..38567f69fbf52ba26f6c101e42007b9ff06ec292 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2009-03-27  Xinliang David Li  <davidxl@google.com>
+
+       PR tree-optimization/39557
+       * g++.dg/tree-ssa/dom-invalid.C: New test.
+
 2009-03-27  Xinliang David Li  <davidxl@google.com>
 
        PR tree-optimization/39548

diff --git a/gcc/testsuite/g++.dg/tree-ssa/dom-invalid.C b/gcc/testsuite/g++.dg/tree-ssa/dom-invalid.C
new file mode 100644 (file)
index 0000000..5513d36
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tree-ssa/dom-invalid.C
@@ -0,0 +1,52 @@
+// PR tree-optimization/39557
+// invalid post-dom info leads to infinite loop
+// { dg-do run }
+// { dg-options "-Wall -fno-exceptions -O2 -fprofile-use -fno-rtti" }
+
+struct C
+{
+ virtual const char *bar () const;
+};
+
+struct D
+{
+ D () : d1 (0) { }
+ C *d2[4];
+ int d1;
+ inline const C & baz (int i) const { return *d2[i]; }
+};
+
+struct E
+{
+ unsigned char e1[2];
+ D e2;
+ bool foo () const { return (e1[1] & 1) != 0; }
+ virtual const char *bar () const __attribute__ ((noinline));
+};
+
+const char *
+C::bar () const
+{
+ return 0;
+}
+
+C c;
+
+const char *
+E::bar () const
+{
+ const char *e = __null;
+ if (foo () && (e = c.C::bar ()))
+   return e;
+ for (int i = 0, n = e2.d1; i < n; i++)
+   if ((e = e2.baz (i).C::bar ()))
+     return e;
+ return e;
+}
+
+int
+main ()
+{
+ E e;
+ e.bar ();
+} // { dg-message  "note: file" "" }

diff --git a/gcc/tree-ssa.c b/gcc/tree-ssa.c
index b26884b1b27271ddfb2b008b61f62e4deb74b28d..8be2961f89538b757fa6bd985e24c59cd614c82b 100644 (file)
--- a/gcc/tree-ssa.c
+++ b/gcc/tree-ssa.c
@@ -1589,6 +1589,11 @@ warn_uninitialized_vars (bool warn_possibly_uninitialized)
          walk_gimple_op (gsi_stmt (gsi), warn_uninitialized_var, &wi);
        }
     }
+
+  /* Post-dominator information can not be reliably updated. Free it
+     after the use.  */
+
+  free_dominance_info (CDI_POST_DOMINATORS);
   return 0;
 }