PR c/44715

	* cp-gimplify.c (genericize_cp_loop): Call begin_bc_block only
	after genericizing cond and incr expressions.

	* doc/extend.texi: Document break and continue behavior in
	statement expressions.

	* c-c++-common/pr44715.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@268188 138bc75d-0d04-0410-961f-82ee72b054a4

6 files changed, 197 insertions, 5 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bbbacebf4cb..401b81d75c7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2019-01-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/44715
+	* doc/extend.texi: Document break and continue behavior in
+	statement expressions.
+
 2019-01-23  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/89008
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 363dff135cf..a36fe31ca23 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2019-01-23  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c/44715
+	* cp-gimplify.c (genericize_cp_loop): Call begin_bc_block only
+	after genericizing cond and incr expressions.
+
 	PR c++/88984
 	* cp-gimplify.c (genericize_switch_stmt): Move cond genericization
 	before the begin_bc_block call.
diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c
index e476b8f53ec..33111bd14bf 100644
--- a/gcc/cp/cp-gimplify.c
+++ b/gcc/cp/cp-gimplify.c
@@ -242,14 +242,15 @@ genericize_cp_loop (tree *stmt_p, location_t start_locus, tree cond, tree body,
   tree exit = NULL;
   tree stmt_list = NULL;
 
-  blab = begin_bc_block (bc_break, start_locus);
-  clab = begin_bc_block (bc_continue, start_locus);
-
   protected_set_expr_location (incr, start_locus);
 
   cp_walk_tree (&cond, cp_genericize_r, data, NULL);
-  cp_walk_tree (&body, cp_genericize_r, data, NULL);
   cp_walk_tree (&incr, cp_genericize_r, data, NULL);
+
+  blab = begin_bc_block (bc_break, start_locus);
+  clab = begin_bc_block (bc_continue, start_locus);
+
+  cp_walk_tree (&body, cp_genericize_r, data, NULL);
   *walk_subtrees = 0;
 
   if (cond && TREE_CODE (cond) != INTEGER_CST)
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 2f3f10b911e..4044fba753e 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -213,7 +213,14 @@ statement expression is part of a larger expression then it is
 unspecified which other subexpressions of that expression have been
 evaluated except where the language definition requires certain
 subexpressions to be evaluated before or after the statement
-expression.  In any case, as with a function call, the evaluation of a
+expression.  A @code{break} or @code{continue} statement inside of
+a statement expression used in @code{while}, @code{do} or @code{for}
+loop or @code{switch} statement condition
+or @code{for} statement init or increment expressions jumps to an
+outer loop or @code{switch} statement if any (otherwise it is an error),
+rather than to the loop or @code{switch} statement in whose condition
+or init or increment expression it appears.
+In any case, as with a function call, the evaluation of a
 statement expression is not interleaved with the evaluation of other
 parts of the containing expression.  For example,
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c6006e0655b..38fec831cb8 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2019-01-23  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c/44715
+	* c-c++-common/pr44715.c: New test.
+
 	PR c++/88984
 	* c-c++-common/pr88984.c: New test.
 
diff --git a/gcc/testsuite/c-c++-common/pr44715.c b/gcc/testsuite/c-c++-common/pr44715.c
new file mode 100644
index 00000000000..f20a14688fa
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr44715.c
@@ -0,0 +1,171 @@
+/* PR c/44715 */
+/* { dg-do run } */
+/* { dg-options "" } */
+
+void
+foo (int x, int y)
+{
+  int z;
+  switch (x)
+    {
+    case 0:
+      while (({ if (y) break; 0; }))
+	;
+      __builtin_abort ();
+      break;
+    case 1:
+      do
+	;
+      while (({ if (y) break; 0; }));
+      __builtin_abort ();
+      break;
+    case 2:
+      for (z = ({ if (y) break; 0; }); z < 5; z++)
+	;
+      __builtin_abort ();
+      break;
+    case 3:
+      for (z = 0; z < ({ if (y) break; 5; }); z++)
+	;
+      __builtin_abort ();
+      break;
+    case 4:
+      for (z = 0; z < 5; z += ({ if (y) break; 1; }))
+	;
+      __builtin_abort ();
+      break;
+    case 5:
+      switch (({ if (y) break; 1; }))
+	{
+	default: break;
+	}
+      __builtin_abort ();
+      break;
+    default:
+      __builtin_abort ();
+      break;
+    }
+}
+
+void
+bar (int x, int y)
+{
+  int z;
+  while (x >= 0)
+    {
+      if (x == 0)
+	{
+	  while (({ if (y) break; 0; }))
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 1)
+	{
+	  do
+	    ;
+	  while (({ if (y) break; 0; }));
+	  __builtin_abort ();
+	}
+      if (x == 2)
+	{
+	  for (z = ({ if (y) break; 0; }); z < 5; z++)
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 3)
+	{
+	  for (z = 0; z < ({ if (y) break; 5; }); z++)
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 4)
+	{
+	  for (z = 0; z < 5; z += ({ if (y) break; 1; }))
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 5)
+	{
+	  switch (({ if (y) break; 1; }))
+	    {
+	    default: break;
+	    }
+	  __builtin_abort ();
+	}
+    }
+}
+
+void
+baz (int x, int y)
+{
+  int z;
+  while (x >= 0)
+    {
+      if (++y == 2)
+	return;
+      if (x == 0)
+	{
+	  while (({ if (y) continue; 0; }))
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 1)
+	{
+	  do
+	    ;
+	  while (({ if (y) continue; 0; }));
+	  __builtin_abort ();
+	}
+      if (x == 2)
+	{
+	  for (z = ({ if (y) continue; 0; }); z < 5; z++)
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 3)
+	{
+	  for (z = 0; z < ({ if (y) continue; 5; }); z++)
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 4)
+	{
+	  for (z = 0; z < 5; z += ({ if (y) continue; 1; }))
+	    ;
+	  __builtin_abort ();
+	}
+      if (x == 5)
+	{
+	  switch (({ if (y) continue; 1; }))
+	    {
+	    default: break;
+	    }
+	  __builtin_abort ();
+	}
+    }
+  __builtin_abort ();
+}
+
+int
+main ()
+{
+  foo (0, 1);
+  foo (1, 1);
+  foo (2, 1);
+  foo (3, 1);
+  foo (4, 1);
+  foo (5, 1);
+  bar (0, 1);
+  bar (1, 1);
+  bar (2, 1);
+  bar (3, 1);
+  bar (4, 1);
+  bar (5, 1);
+  baz (0, 0);
+  baz (1, 0);
+  baz (2, 0);
+  baz (3, 0);
+  baz (4, 0);
+  baz (5, 0);
+  return 0;
+}