[PATCH] D50630: [AST] Update/correct the static_asserts for the bit-fields in Type

[Bruno Ricci via Phabricator via cfe-commits]

riccibruno created this revision.
riccibruno added reviewers: erichkeane, rjmccall.
riccibruno added a project: clang.
Herald added a subscriber: cfe-commits.

The current static_assert only checks that ObjCObjectTypeBitfields
fits into an unsigned. However it turns out that FunctionTypeBitfields
do not currently fits into an unsigned. Therefore the anonymous
union containing the bit-fields always use 8 bytes instead of 4.

This patch remove the lone misguided static_assert and systematically
check the size of each bit-field.


Repository:
  rC Clang

https://reviews.llvm.org/D50630

Files:
  include/clang/AST/Type.h


Index: include/clang/AST/Type.h
===================================================================
--- include/clang/AST/Type.h
+++ include/clang/AST/Type.h
@@ -1557,8 +1557,6 @@
     unsigned IsKindOf : 1;
   };
 
-  static_assert(NumTypeBits + 7 + 6 + 1 <= 32, "Does not fit in an unsigned");
-
   class ReferenceTypeBitfields {
     friend class ReferenceType;
 
@@ -1637,6 +1635,27 @@
     ReferenceTypeBitfields ReferenceTypeBits;
     TypeWithKeywordBitfields TypeWithKeywordBits;
     VectorTypeBitfields VectorTypeBits;
+
+    static_assert(sizeof(TypeBitfields) <= 4,
+                  "TypeBitfields is larger than 4 bytes!");
+    static_assert(sizeof(ArrayTypeBitfields) <= 8,
+                  "ArrayTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(AttributedTypeBitfields) <= 8,
+                  "AttributedTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(AutoTypeBitfields) <= 8,
+                  "AutoTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(BuiltinTypeBitfields) <= 8,
+                  "BuiltinTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(FunctionTypeBitfields) <= 8,
+                  "FunctionTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(ObjCObjectTypeBitfields) <= 8,
+                  "ObjCObjectTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(ReferenceTypeBitfields) <= 8,
+                  "ReferenceTypeBitfields is larger than 8 bytes!");
+    static_assert(sizeof(TypeWithKeywordBitfields) <= 8,
+                  "TypeWithKeywordBitfields is larger than 8 bytes!");
+    static_assert(sizeof(VectorTypeBitfields) <= 8,
+                  "VectorTypeBitfields is larger than 8 bytes!");
   };
 
 private:


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D50630.160321.patch
Type: text/x-patch
Size: 1769 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20180813/86deafa5/attachment.bin>