1 files changed, 142 insertions, 0 deletions

diff --git a/meta/recipes-devtools/gcc/gcc-4.6.0/gcc-4_6-branch-backports/0327-PR-c-49136.patch b/meta/recipes-devtools/gcc/gcc-4.6.0/gcc-4_6-branch-backports/0327-PR-c-49136.patch
new file mode 100644
index 0000000000..dcf00aece5
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc-4.6.0/gcc-4_6-branch-backports/0327-PR-c-49136.patch
@@ -0,0 +1,142 @@
+From aa15fbe864f58be935154f76f8ebf144988e7746 Mon Sep 17 00:00:00 2001
+From: jakub <jakub@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date: Wed, 25 May 2011 07:03:25 +0000
+Subject: [PATCH]        PR c++/49136
+        * semantics.c (cxx_eval_bit_field_ref): Handle the
+        case when BIT_FIELD_REF doesn't cover only a single field.
+
+        * g++.dg/cpp0x/constexpr-bitfield2.C: New test.
+        * g++.dg/cpp0x/constexpr-bitfield3.C: New test.
+
+
+git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@174169 138bc75d-0d04-0410-961f-82ee72b054a4
+
+index bd33bac..6207b12 100644
+--- a/gcc/cp/semantics.c
++++ b/gcc/cp/semantics.c
+@@ -6391,6 +6391,9 @@ cxx_eval_bit_field_ref (const constexpr_call *call, tree t,
+                        bool *non_constant_p)
+ {
+   tree orig_whole = TREE_OPERAND (t, 0);
++  tree retval, fldval, utype, mask;
++  bool fld_seen = false;
++  HOST_WIDE_INT istart, isize;
+   tree whole = cxx_eval_constant_expression (call, orig_whole,
+                                             allow_non_constant, addr,
+                                             non_constant_p);
+@@ -6411,12 +6414,47 @@ cxx_eval_bit_field_ref (const constexpr_call *call, tree t,
+     return t;
+ 
+   start = TREE_OPERAND (t, 2);
++  istart = tree_low_cst (start, 0);
++  isize = tree_low_cst (TREE_OPERAND (t, 1), 0);
++  utype = TREE_TYPE (t);
++  if (!TYPE_UNSIGNED (utype))
++    utype = build_nonstandard_integer_type (TYPE_PRECISION (utype), 1);
++  retval = build_int_cst (utype, 0);
+   FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (whole), i, field, value)
+     {
+-      if (bit_position (field) == start)
++      tree bitpos = bit_position (field);
++      if (bitpos == start && DECL_SIZE (field) == TREE_OPERAND (t, 1))
+        return value;
++      if (TREE_CODE (TREE_TYPE (field)) == INTEGER_TYPE
++         && TREE_CODE (value) == INTEGER_CST
++         && host_integerp (bitpos, 0)
++         && host_integerp (DECL_SIZE (field), 0))
++       {
++         HOST_WIDE_INT bit = tree_low_cst (bitpos, 0);
++         HOST_WIDE_INT sz = tree_low_cst (DECL_SIZE (field), 0);
++         HOST_WIDE_INT shift;
++         if (bit >= istart && bit + sz <= istart + isize)
++           {
++             fldval = fold_convert (utype, value);
++             mask = build_int_cst_type (utype, -1);
++             mask = fold_build2 (LSHIFT_EXPR, utype, mask,
++                                 size_int (TYPE_PRECISION (utype) - sz));
++             mask = fold_build2 (RSHIFT_EXPR, utype, mask,
++                                 size_int (TYPE_PRECISION (utype) - sz));
++             fldval = fold_build2 (BIT_AND_EXPR, utype, fldval, mask);
++             shift = bit - istart;
++             if (BYTES_BIG_ENDIAN)
++               shift = TYPE_PRECISION (utype) - shift - sz;
++             fldval = fold_build2 (LSHIFT_EXPR, utype, fldval,
++                                   size_int (shift));
++             retval = fold_build2 (BIT_IOR_EXPR, utype, retval, fldval);
++             fld_seen = true;
++           }
++       }
+     }
+-  gcc_unreachable();
++  if (fld_seen)
++    return fold_convert (TREE_TYPE (t), retval);
++  gcc_unreachable ();
+   return error_mark_node;
+ }
+ 
+new file mode 100644
+index 0000000..531bf31
+--- /dev/null
++++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-bitfield2.C
+@@ -0,0 +1,19 @@
++// PR c++/49136
++// { dg-do compile }
++// { dg-options "-std=c++0x" }
++
++struct day
++{
++  unsigned d : 5;
++  unsigned n : 3;
++  constexpr explicit day (int dd) : d(dd), n(7) {}
++};
++
++struct date {
++  int d;
++  constexpr date (day dd) : d(dd.n != 7 ? 7 : dd.d) {}
++};
++
++constexpr day d(0);
++constexpr date dt(d);
++static_assert (dt.d == 0, "Error");
+diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-bitfield3.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-bitfield3.C
+new file mode 100644
+index 0000000..b0ecbfb
+--- /dev/null
++++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-bitfield3.C
+@@ -0,0 +1,33 @@
++// PR c++/49136
++// { dg-do compile }
++// { dg-options "-std=c++0x" }
++
++struct S
++{
++  unsigned : 1; unsigned s : 27; unsigned : 4;
++  constexpr S (unsigned int x) : s(x) {}
++};
++
++template <typename S>
++struct T
++{
++  unsigned int t;
++  constexpr T (S s) : t(s.s != 7 ? 0 : s.s) {}
++  constexpr T (S s, S s2) : t(s.s != s2.s ? 0 : s.s) {}
++};
++
++constexpr S s (7), s2 (7);
++constexpr T<S> t (s), t2 (s, s2);
++static_assert (t.t == 7, "Error");
++static_assert (t2.t == 7, "Error");
++
++struct U
++{
++  int a : 1; int s : 1;
++  constexpr U (int x, int y) : a (x), s (y) {}
++};
++
++constexpr U u (0, -1), u2 (-1, -1);
++constexpr T<U> t3 (u), t4 (u, u2);
++static_assert (t3.t == 0, "Error");
++static_assert (t4.t == -1, "Error");
+-- 
+1.7.0.4
+