From: David Majnemer <david.majnemer@gmail.com>
Date: Tue, 15 Sep 2015 01:00:55 +0000 (+0000)
Subject: [MS ABI] Overwide bool bitfields should be permitted
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f4a9596475bc09ffe2ef232b68feb81a6e204402;p=clang

[MS ABI] Overwide bool bitfields should be permitted

Overwide bool bitfields have eight bits of storage size, make sure we
take the padding into account when determining whether or not they are
problematic.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@247651 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 8501bc5b22..9c641ddbb6 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -12626,11 +12626,14 @@ ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
   }
 
   if (!FieldTy->isDependentType()) {
-    uint64_t TypeWidth = Context.getIntWidth(FieldTy);
+    bool UseMSBitfieldSemantics =
+        IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft();
+    bool UseStorageSize = getLangOpts().CPlusPlus && UseMSBitfieldSemantics;
+    uint64_t TypeWidth = UseStorageSize ? Context.getTypeSize(FieldTy)
+                                        : Context.getIntWidth(FieldTy);
     if (Value.ugt(TypeWidth)) {
-      if (!getLangOpts().CPlusPlus || IsMsStruct ||
-          Context.getTargetInfo().getCXXABI().isMicrosoft()) {
-        if (FieldName) 
+      if (!getLangOpts().CPlusPlus || UseMSBitfieldSemantics) {
+        if (FieldName)
           return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
             << FieldName << (unsigned)Value.getZExtValue() 
             << (unsigned)TypeWidth;
diff --git a/test/SemaCXX/ms_wide_bitfield.cpp b/test/SemaCXX/ms_wide_bitfield.cpp
index 2b11579a5c..022d604ec1 100644
--- a/test/SemaCXX/ms_wide_bitfield.cpp
+++ b/test/SemaCXX/ms_wide_bitfield.cpp
@@ -3,8 +3,8 @@
 struct A {
   char a : 9; // expected-error{{width of bit-field 'a' (9 bits) exceeds width of its type (8 bits)}}
   int b : 33; // expected-error{{width of bit-field 'b' (33 bits) exceeds width of its type (32 bits)}}
-  bool c : 9; // expected-error{{width of bit-field 'c' (9 bits) exceeds width of its type (1 bit)}}
-  bool d : 3; // expected-error{{width of bit-field 'd' (3 bits) exceeds width of its type (1 bit)}}
+  bool c : 9; // expected-error{{width of bit-field 'c' (9 bits) exceeds width of its type (8 bits)}}
+  bool d : 3;
 };
 
 int a[sizeof(A) == 1 ? 1 : -1];