From b28cf1b0833df0850bb862aaf093fafb7babe400 Mon Sep 17 00:00:00 2001
From: msebor <msebor@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 31 Jul 2018 16:47:39 +0000
Subject: [PATCH] PR tree-optimization/86741 - ICE in -Warray-bounds indexing
 into an object of incomplete type

gcc/ChangeLog:

	PR tree-optimization/86741
	* tree-vrp.c (vrp_prop::check_mem_ref): Avoid incomplete types.

gcc/testsuite/ChangeLog:

	PR tree-optimization/86741
	* gcc.dg/Warray-bounds-33.c: New test.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@263166 138bc75d-0d04-0410-961f-82ee72b054a4
---
 gcc/ChangeLog                           |  5 +++++
 gcc/testsuite/ChangeLog                 |  5 +++++
 gcc/testsuite/gcc.dg/Warray-bounds-33.c | 36 +++++++++++++++++++++++++++++++++
 gcc/tree-vrp.c                          |  5 ++++-
 4 files changed, 50 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.dg/Warray-bounds-33.c

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 50bd14c7af1..bcaa74cfbd6 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2018-07-31  Martin Sebor  <msebor@redhat.com>
+
+	PR tree-optimization/86741
+	* tree-vrp.c (vrp_prop::check_mem_ref): Avoid incomplete types.
+
 2018-07-31  Andreas Krebbel  <krebbel@linux.ibm.com>
 
 	* config/s390/s390.c (s390_expand_setmem): Make the unrolling to
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f741d280fd5..a6a13b3cba9 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-07-31  Martin Sebor  <msebor@redhat.com>
+
+	PR tree-optimization/86741
+	* gcc.dg/Warray-bounds-33.c: New test.
+
 2018-07-31  Andreas Krebbel  <krebbel@linux.ibm.com>
 
 	* gcc.target/s390/memset-1.c: Improve testcase.
diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-33.c b/gcc/testsuite/gcc.dg/Warray-bounds-33.c
new file mode 100644
index 00000000000..28f14b4722c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Warray-bounds-33.c
@@ -0,0 +1,36 @@
+/* PR tree-optimization/86741 - ICE in -Warray-bounds indexing into
+   an object of incomplete type
+   { dg-do compile }
+   { dg-options "-O2 -Wall" }  */
+
+struct S
+{
+  int s;
+};
+
+void f (void);
+
+void test_void (void)
+{
+  extern void v;
+  struct S *b = (struct S*)&v;
+  if (b->s)
+    f ();
+}
+
+void test_incomplete_enum (void)
+{
+  extern enum E e;
+  struct S *b = (struct S*)&e;
+  if (b->s)
+    f ();
+}
+
+void test_func (void)
+{
+  struct S *b = (struct S*)&f;
+  if (b->s)
+    f ();
+}
+
+/* { dg-prune-output "taking address of expression of type .void." } */
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 7ab8898b453..1944ae4f4db 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -5048,9 +5048,12 @@ vrp_prop::check_mem_ref (location_t location, tree ref, bool ignore_off_by_one)
      a reference/subscript via a pointer to an object that is not
      an element of an array.  References to members of structs and
      unions are excluded because MEM_REF doesn't make it possible
-     to identify the member where the reference originated.  */
+     to identify the member where the reference originated.
+     Incomplete types are excluded as well because their size is
+     not known.  */
   tree reftype = TREE_TYPE (arg);
   if (POINTER_TYPE_P (reftype)
+      || !COMPLETE_TYPE_P (reftype)
       || RECORD_OR_UNION_TYPE_P (reftype))
     return;
 
-- 
2.11.4.GIT