Teach __alignof__ to look through arrays before performing the
preferred-alignment transformations. Corrects alignof(T[]) to return
alignof(T) in all cases, as required by relevant standards.
llvm-svn: 210609
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index f78f2a9..eaf77e9 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -1328,15 +1328,6 @@
MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
Align = std::max(Align, Target->getLargeArrayAlign());
}
-
- // Keep track of extra alignment requirements on the array itself, then
- // work with the element type.
- //
- // FIXME: Computing the preferred type alignment for the array element
- // type should not be necessary, but getPreferredTypeAlign returns the
- // wrong thing in some cases (such as 'long long[]' on x86_64).
- Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
- T = BaseT;
}
Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
@@ -1788,6 +1779,7 @@
const TypedefType *TT = T->getAs<TypedefType>();
// Double and long long should be naturally aligned if possible.
+ T = T->getBaseElementTypeUnsafe();
if (const ComplexType *CT = T->getAs<ComplexType>())
T = CT->getElementType().getTypePtr();
if (T->isSpecificBuiltinType(BuiltinType::Double) ||
diff --git a/clang/test/Sema/align-x86.c b/clang/test/Sema/align-x86.c
index 6b93a48..f112c63 100644
--- a/clang/test/Sema/align-x86.c
+++ b/clang/test/Sema/align-x86.c
@@ -23,6 +23,10 @@
short chk1[__alignof__(g4) == 1 ? 1 : -1];
short chk2[__alignof__(g4.a) == 1 ? 1 : -1];
+double g6[3];
+short chk1[__alignof__(g6) == 8 ? 1 : -1];
+short chk2[__alignof__(double[3]) == 8 ? 1 : -1];
+
// PR5637