PR middle-end/6994

	* c-objc-common.c (inline_forbidden_p): Can not inline
	functions containing structures or unions containing VLAs.
	* tree-inline.c (walk_tree): For all class 't' nodes, walk
	TYPE_SIZE and TYPE_SIZE_UNIT.
	(copy_tree_r): Copy types if they are variably modified.

	* g++.dg/ext/vla1.C, gcc.dg/vla-2.c: New tests.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@58535 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 16 insertions, 0 deletions

diff --git a/gcc/c-objc-common.c b/gcc/c-objc-common.c
index e279911acc0..2d67b8f21c0 100644
--- a/gcc/c-objc-common.c
+++ b/gcc/c-objc-common.c
@@ -133,6 +133,22 @@ inline_forbidden_p (nodep, walk_subtrees, fn)
 
       break;
 
+    case RECORD_TYPE:
+    case UNION_TYPE:
+      /* We cannot inline a function of the form
+
+	   void F (int i) { struct S { int ar[i]; } s; }
+
+	 Attempting to do so produces a catch-22 in tree-inline.c.
+	 If walk_tree examines the TYPE_FIELDS chain of RECORD_TYPE/
+	 UNION_TYPE nodes, then it goes into infinite recursion on a
+	 structure containing a pointer to its own type.  If it doesn't,
+	 then the type node for S doesn't get adjusted properly when
+	 F is inlined, and we abort in find_function_data.  */
+      for (t = TYPE_FIELDS (node); t; t = TREE_CHAIN (t))
+	if (variably_modified_type_p (TREE_TYPE (t)))
+	  return node;
+
     default:
       break;
     }