2008-05-08 Richard Guenther <rguenther@suse.de>

	PR middle-end/36154
	* tree-ssa-structalias.c (push_fields_onto_fieldstack): Make
	sure to create a representative for trailing arrays for PTA.

	* gcc.c-torture/compile/pr36154.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@135071 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bdc4846..1121be1 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,11 @@
 2008-05-08  Richard Guenther  <rguenther@suse.de>
 
+       PR middle-end/36154
+       * tree-ssa-structalias.c (push_fields_onto_fieldstack): Make
+       sure to create a representative for trailing arrays for PTA.
+
+2008-05-08  Richard Guenther  <rguenther@suse.de>
+
        PR middle-end/36172
        * fold-const.c (operand_equal_p): Two objects which types
        differ in pointerness are not equal.

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 68626fd..2b137fa 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2008-05-08  Richard Guenther  <rguenther@suse.de>
 
+       PR middle-end/36154
+       * gcc.c-torture/compile/pr36154.c: New testcase.
+
+2008-05-08  Richard Guenther  <rguenther@suse.de>
+
        PR middle-end/36172
        * gcc.c-torture/compile/pr36172.c: New testcase.
 

diff --git a/gcc/testsuite/gcc.c-torture/compile/pr36154.c b/gcc/testsuite/gcc.c-torture/compile/pr36154.c
new file mode 100644 (file)
index 0000000..ae3eb83
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr36154.c
@@ -0,0 +1,11 @@
+struct eth_test_pkt {
+  unsigned short len;
+  unsigned short ctr;
+  unsigned char packet[];
+} __attribute__ ((packed));
+struct eth_test_pkt pkt_unaligned = { .packet = { 0xFC } };
+int cmd_unaligned(const void *p)
+{
+  return memcmp(p, pkt_unaligned.packet, 1);
+}
+

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index ddcf498..d58478e 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -4160,11 +4160,15 @@ push_fields_onto_fieldstack (tree type, VEC(fieldoff_s,heap) **fieldstack,
                        (DECL_NONADDRESSABLE_P (field)
                         ? addressable_type
                         : TREE_TYPE (field))))
-                    && DECL_SIZE (field)
-                    && !integer_zerop (DECL_SIZE (field)))
-             /* Empty structures may have actual size, like in C++. So
+                    && ((DECL_SIZE (field)
+                         && !integer_zerop (DECL_SIZE (field)))
+                        || (!DECL_SIZE (field)
+                            && TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE)))
+             /* Empty structures may have actual size, like in C++.  So
                 see if we didn't push any subfields and the size is
-                nonzero, push the field onto the stack */
+                nonzero, push the field onto the stack.  Trailing flexible
+                array members also need a representative to be able to
+                treat taking their address in PTA.  */
              push = true;
 
            if (push)