[C++ PATCH] Fix another y && (x ? 1 : throw 1) issue (PR c++/49165)

[Jakub Jelinek <jakub@redhat.com>]

Hi!

As the testcase shows (it is eh/cond5.C just with s/true :/1 :/g),
c_common_truthvalue_conversion needs to be aware of void type arms
too, otherwise it errors on valid source.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk/4.6?

2011-05-27  Jakub Jelinek  <jakub@redhat.com>

	PR c++/49165
	* c-common.c (c_common_truthvalue_conversion) <case COND_EXPR>: For
	C++ don't call c_common_truthvalue_conversion on void type arms.

	* g++.dg/eh/cond6.C: New test.

--- gcc/c-family/c-common.c.jj	2011-05-25 16:50:57.000000000 +0200
+++ gcc/c-family/c-common.c	2011-05-27 14:22:06.000000000 +0200
@@ -3942,14 +3942,15 @@ c_common_truthvalue_conversion (location
       /* Distribute the conversion into the arms of a COND_EXPR.  */
       if (c_dialect_cxx ())
 	{
+	  tree op1 = TREE_OPERAND (expr, 1);
+	  tree op2 = TREE_OPERAND (expr, 2);
+	  /* In C++ one of the arms might have void type if it is throw.  */
+	  if (!VOID_TYPE_P (TREE_TYPE (op1)))
+	    op1 = c_common_truthvalue_conversion (location, op1);
+	  if (!VOID_TYPE_P (TREE_TYPE (op2)))
+	    op2 = c_common_truthvalue_conversion (location, op2);
 	  expr = fold_build3_loc (location, COND_EXPR, truthvalue_type_node,
-			      TREE_OPERAND (expr, 0),
-			      c_common_truthvalue_conversion (location,
-							      TREE_OPERAND (expr,
-									    1)),
-			      c_common_truthvalue_conversion (location,
-							      TREE_OPERAND (expr,
-									    2)));
+				  TREE_OPERAND (expr, 0), op1, op2);
 	  goto ret;
 	}
       else
--- gcc/testsuite/g++.dg/eh/cond6.C.jj	2011-05-27 14:25:02.000000000 +0200
+++ gcc/testsuite/g++.dg/eh/cond6.C	2011-05-27 14:13:17.000000000 +0200
@@ -0,0 +1,43 @@
+// PR c++/49165
+// { dg-do run }
+
+extern "C" void abort ();
+
+int
+foo (bool x, int y)
+{
+  if (y < 10 && (x ? 1 : throw 1))
+    y++;
+  if (y > 20 || (x ? 1 : throw 2))
+    y++;
+  return y;
+}
+
+int
+main ()
+{
+  if (foo (true, 0) != 2
+      || foo (true, 10) != 11
+      || foo (false, 30) != 31)
+    abort ();
+  try
+    {
+      foo (false, 0);
+      abort ();
+    }
+  catch (int i)
+    {
+      if (i != 1)
+	abort ();
+    }
+  try
+    {
+      foo (false, 10);
+      abort ();
+    }
+  catch (int i)
+    {
+      if (i != 2)
+	abort ();
+    }
+}

	Jakub