From 7b6d72fcfbd0aa2bb05d81afcdcf5e4c6027b2e8 Mon Sep 17 00:00:00 2001
From: Mark Mitchell <mmitchel@gcc.gnu.org>
Date: Tue, 29 Jul 2003 01:14:24 +0000
Subject: re PR c++/11667 (wider-than-int enums never compare equal to 0)

	PR c++/11667
	* c-common.c (shorten_compare): Take into account differences
	between C and C++ representation for enumeration types.
	* tree.h (set_min_and_max_values_for_integral_type): Declare.
	* stor-layout.c (set_min_and_max_values_for_integral_type): New
	function, broken out from ...
	(fixup_signed_type): ... here and ...
	(fixup_unsigned_type): ... here.

	PR c++/11667
	* call.c (standard_conversion): Allow all integral->enumeral
	conversions, after marking them as bad.
	* decl.c (finish_enum): Make sure that all enumerators are
	properly converted to the underlying type.
	(build_enumerator): Set DECL_CONTEXT for namespace-scope
	enumeration types.
	* pt.c (tsubst_copy): Adjust handling of CONST_DECLs accordingly.
	(tsubst_enum): Tidy.

	* Make-lang.in (typeck.o): Depend on convert.h.
	(class.o): Likewise.
	(rtti.o): Likewise.
	* call.c: Include convert.h.
	(convert_arg_to_ellipsis): Use convert_to_real.
	* class.c: Include convert.h.
	(build_base_path): Use convert_to_integer.
	* rtti.c: Include convert.h.
	(build_headof): Use convert_to_integer.
	* typeck.c: Include convert.h.
	(decay_conversion): Use convert_to_integer.
	(build_unary_op): Use build_nop.
	(get_delta_difference): Use convert_to_integer.
	(build_ptrmemfunc): Avoid unncessary conversions.

From-SVN: r69909
---
 gcc/stor-layout.c | 84 ++++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 56 insertions(+), 28 deletions(-)

(limited to 'gcc/stor-layout.c')

diff --git a/gcc/stor-layout.c b/gcc/stor-layout.c
index e2395c4..54e6a56 100644
--- a/gcc/stor-layout.c
+++ b/gcc/stor-layout.c
@@ -1957,6 +1957,58 @@ set_sizetype (tree type)
   sizetype_set = 1;
 }
 
+/* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE,
+   BOOLEAN_TYPE, or CHAR_TYPE.  Set TYPE_MIN_VALUE and TYPE_MAX_VALUE
+   for TYPE, based on the PRECISION and whether or not the TYPE
+   IS_UNSIGNED.  PRECISION need not correspond to a width supported
+   natively by the hardware; for example, on a machine with 8-bit,
+   16-bit, and 32-bit register modes, PRECISION might be 7, 23, or
+   61.  */
+
+void
+set_min_and_max_values_for_integral_type (tree type,
+					  int precision,
+					  bool is_unsigned)
+{
+  tree min_value;
+  tree max_value;
+
+  if (is_unsigned)
+    {
+      min_value = build_int_2 (0, 0);
+      max_value 
+	= build_int_2 (precision - HOST_BITS_PER_WIDE_INT >= 0
+		       ? -1 : ((HOST_WIDE_INT) 1 << precision) - 1,
+		       precision - HOST_BITS_PER_WIDE_INT > 0
+		       ? ((unsigned HOST_WIDE_INT) ~0
+			  >> (HOST_BITS_PER_WIDE_INT
+			      - (precision - HOST_BITS_PER_WIDE_INT)))
+		       : 0);
+    }
+  else
+    {
+      min_value 
+	= build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0
+			? 0 : (HOST_WIDE_INT) (-1) << (precision - 1)),
+		       (((HOST_WIDE_INT) (-1)
+			 << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
+			     ? precision - HOST_BITS_PER_WIDE_INT - 1
+			     : 0))));    
+      max_value
+	= build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0
+			? -1 : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1),
+		       (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
+			? (((HOST_WIDE_INT) 1
+			    << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1
+			: 0));
+    }
+
+  TREE_TYPE (min_value) = type;
+  TREE_TYPE (max_value) = type;
+  TYPE_MIN_VALUE (type) = min_value;
+  TYPE_MAX_VALUE (type) = max_value;
+}
+
 /* Set the extreme values of TYPE based on its precision in bits,
    then lay it out.  Used when make_signed_type won't do
    because the tree code is not INTEGER_TYPE.
@@ -1973,23 +2025,8 @@ fixup_signed_type (tree type)
   if (precision > HOST_BITS_PER_WIDE_INT * 2)
     precision = HOST_BITS_PER_WIDE_INT * 2;
 
-  TYPE_MIN_VALUE (type)
-    = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0
-		    ? 0 : (HOST_WIDE_INT) (-1) << (precision - 1)),
-		   (((HOST_WIDE_INT) (-1)
-		     << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
-			 ? precision - HOST_BITS_PER_WIDE_INT - 1
-			 : 0))));
-  TYPE_MAX_VALUE (type)
-    = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0
-		    ? -1 : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1),
-		   (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
-		    ? (((HOST_WIDE_INT) 1
-			<< (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1
-		    : 0));
-
-  TREE_TYPE (TYPE_MIN_VALUE (type)) = type;
-  TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
+  set_min_and_max_values_for_integral_type (type, precision, 
+					    /*is_unsigned=*/false);
 
   /* Lay out the type: set its alignment, size, etc.  */
   layout_type (type);
@@ -2010,17 +2047,8 @@ fixup_unsigned_type (tree type)
   if (precision > HOST_BITS_PER_WIDE_INT * 2)
     precision = HOST_BITS_PER_WIDE_INT * 2;
 
-  TYPE_MIN_VALUE (type) = build_int_2 (0, 0);
-  TYPE_MAX_VALUE (type)
-    = build_int_2 (precision - HOST_BITS_PER_WIDE_INT >= 0
-		   ? -1 : ((HOST_WIDE_INT) 1 << precision) - 1,
-		   precision - HOST_BITS_PER_WIDE_INT > 0
-		   ? ((unsigned HOST_WIDE_INT) ~0
-		      >> (HOST_BITS_PER_WIDE_INT
-			  - (precision - HOST_BITS_PER_WIDE_INT)))
-		   : 0);
-  TREE_TYPE (TYPE_MIN_VALUE (type)) = type;
-  TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
+  set_min_and_max_values_for_integral_type (type, precision, 
+					    /*is_unsigned=*/true);
 
   /* Lay out the type: set its alignment, size, etc.  */
   layout_type (type);
-- 
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