2006-05-07 Richard Guenther <rguenther@suse.de>

	PR tree-optimization/27409
	* tree-ssa-structalias.c (get_constraint_for_component_ref):
	Do not try to find zero-sized subvars.

	* gcc.dg/torture/pr27409.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@113607 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bc21174..7f3cd34 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,11 @@
 2006-05-07  Richard Guenther  <rguenther@suse.de>
 
+       PR tree-optimization/27409
+       * tree-ssa-structalias.c (get_constraint_for_component_ref):
+       Do not try to find zero-sized subvars.
+
+2006-05-07  Richard Guenther  <rguenther@suse.de>
+
        PR tree-optimization/27136
        * tree-ssa-loop-niter.c (get_val_for): Correct function
        comment, assert requirements.

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5ac84b0..7041216 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2006-05-07  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/27409
+       * gcc.dg/torture/pr27409.c: New testcase.
+
 2006-05-07  Tobias Schlüter  <tobias.schlueter@physik.uni-muenchen.de>
 
        PR fortran/27457

diff --git a/gcc/testsuite/gcc.dg/torture/pr27409.c b/gcc/testsuite/gcc.dg/torture/pr27409.c
new file mode 100644 (file)
index 0000000..430e6c8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr27409.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+
+typedef struct {
+        struct { } z;
+} thang_t;
+
+struct {
+        short           e;
+        thang_t         f;
+        int g;
+} my_struct;
+
+void function(int blaz)
+{
+  thang_t *fp = &my_struct.f;
+  foo(fp);
+}

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index c5b6cab..26dbd0d 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -2378,7 +2378,8 @@ get_constraint_for_component_ref (tree t, VEC(ce_s, heap) **results)
         ignore this constraint. When we handle pointer subtraction,
         we may have to do something cute here.  */
       
-      if (result->offset < get_varinfo (result->var)->fullsize)
+      if (result->offset < get_varinfo (result->var)->fullsize
+         && bitmaxsize != 0)
        {
          /* It's also not true that the constraint will actually start at the
             right offset, it may start in some padding.  We only care about
@@ -2400,6 +2401,12 @@ get_constraint_for_component_ref (tree t, VEC(ce_s, heap) **results)
             embedded in a struct resulting in accessing *only* padding.  */
          gcc_assert (curr || ref_contains_array_ref (orig_t));
        }
+      else if (bitmaxsize == 0)
+       {
+         if (dump_file && (dump_flags & TDF_DETAILS))
+           fprintf (dump_file, "Access to zero-sized part of variable,"
+                    "ignoring\n");
+       }
       else
        if (dump_file && (dump_flags & TDF_DETAILS))
          fprintf (dump_file, "Access to past the end of variable, ignoring\n");