expmed.c (store_bit_field): Assert that BITREGION_START is a multiple of a unit before computing the offset...

	* expmed.c (store_bit_field): Assert that BITREGION_START is a multiple
	of a unit before computing the offset in units.
	* expr.c (get_bit_range): Return the null range if the enclosing record
	is part of a larger bit field.

From-SVN: r185857

1 files changed, 19 insertions, 0 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index c63343e..56ec3fa 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -4458,6 +4458,25 @@ get_bit_range (unsigned HOST_WIDE_INT *bitstart,
       return;
     }
 
+  /* If we have a DECL_BIT_FIELD_REPRESENTATIVE but the enclosing record is
+     part of a larger bit field, then the representative does not serve any
+     useful purpose.  This can occur in Ada.  */
+  if (handled_component_p (TREE_OPERAND (exp, 0)))
+    {
+      enum machine_mode rmode;
+      HOST_WIDE_INT rbitsize, rbitpos;
+      tree roffset;
+      int unsignedp;
+      int volatilep = 0;
+      get_inner_reference (TREE_OPERAND (exp, 0), &rbitsize, &rbitpos,
+			   &roffset, &rmode, &unsignedp, &volatilep, false);
+      if ((rbitpos % BITS_PER_UNIT) != 0)
+	{
+	  *bitstart = *bitend = 0;
+	  return;
+	}
+    }
+
   /* Compute the adjustment to bitpos from the offset of the field
      relative to the representative.  DECL_FIELD_OFFSET of field and
      repr are the same by construction if they are not constants,