re PR c++/84590 (-fsanitize=undefined internal compiler error: tree check: expected...

	PR c++/84590
	* cp-gimplify.c (cp_fully_fold): Unwrap TARGET_EXPR or a CONSTRUCTOR
	wrapped in VIEW_CONVERT_EXPR.

	* c-c++-common/ubsan/shift-11.c: New test.

From-SVN: r258132

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 2d5363c..c74d3bc 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2018-03-02  Marek Polacek  <polacek@redhat.com>
+
+       PR c++/84590
+       * cp-gimplify.c (cp_fully_fold): Unwrap TARGET_EXPR or a CONSTRUCTOR
+       wrapped in VIEW_CONVERT_EXPR.
+
 2018-03-01  Martin Sebor  <msebor@redhat.com>
 
        PR c++/84294

diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c
index 55a9d27..0ddd435 100644 (file)
--- a/gcc/cp/cp-gimplify.c
+++ b/gcc/cp/cp-gimplify.c
@@ -2037,7 +2037,17 @@ cp_fully_fold (tree x)
   /* FIXME cp_fold ought to be a superset of maybe_constant_value so we don't
      have to call both.  */
   if (cxx_dialect >= cxx11)
-    x = maybe_constant_value (x);
+    {
+      x = maybe_constant_value (x);
+      /* Sometimes we are given a CONSTRUCTOR but the call above wraps it into
+        a TARGET_EXPR; undo that here.  */
+      if (TREE_CODE (x) == TARGET_EXPR)
+       x = TARGET_EXPR_INITIAL (x);
+      else if (TREE_CODE (x) == VIEW_CONVERT_EXPR
+              && TREE_CODE (TREE_OPERAND (x, 0)) == CONSTRUCTOR
+              && TREE_TYPE (TREE_OPERAND (x, 0)) == TREE_TYPE (x))
+       x = TREE_OPERAND (x, 0);
+    }
   return cp_fold_rvalue (x);
 }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e15927c..17369ce 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-03-02  Marek Polacek  <polacek@redhat.com>
+
+       PR c++/84590
+       * c-c++-common/ubsan/shift-11.c: New test.
+
 2018-03-02  Richard Sandiford  <richard.sandiford@linaro.org>
 
        * gcc.dg/vect/vect-alias-check-13.c: New test.

diff --git a/gcc/testsuite/c-c++-common/ubsan/shift-11.c b/gcc/testsuite/c-c++-common/ubsan/shift-11.c
new file mode 100644 (file)
index 0000000..03a72e2
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/ubsan/shift-11.c
@@ -0,0 +1,13 @@
+/* PR c++/84590 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=shift" } */
+
+struct S {
+  int b;
+};
+
+void
+fn (void)
+{
+  struct S c1 = { 1 << -1 }; /* { dg-warning "left shift" } */
+}