Fix PR3386 by handling GCC's rules for alignof, which are substantially
different than those for sizeof. Reject alignof(bitfield) like gcc does.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62928 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticKinds.def b/include/clang/Basic/DiagnosticKinds.def
index 1858f25..5cb71fc 100644
--- a/include/clang/Basic/DiagnosticKinds.def
+++ b/include/clang/Basic/DiagnosticKinds.def
@@ -1188,6 +1188,8 @@
"invalid application of 'sizeof' to an incomplete type %0")
DIAG(err_alignof_incomplete_type, ERROR,
"invalid application of '__alignof' to an incomplete type %0")
+DIAG(err_alignof_bitfield, ERROR,
+ "invalid application of '__alignof' to bitfield")
DIAG(err_offsetof_record_type, ERROR,
"offsetof requires struct, union, or class type, %0 invalid")
DIAG(err_offsetof_array_type, ERROR,
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 40cfe8f..a993ebe 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -1003,6 +1003,7 @@
ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType,
void *TyOrEx, const SourceRange &ArgRange);
+ bool CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, const SourceRange &R);
bool CheckSizeOfAlignOfOperand(QualType type, SourceLocation OpLoc,
const SourceRange &R, bool isSizeof);
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index fa4c9d6..56ad4b5 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1035,6 +1035,27 @@
ExprRange);
}
+bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc,
+ const SourceRange &ExprRange) {
+ E = E->IgnoreParens();
+
+ // alignof decl is always ok.
+ if (isa<DeclRefExpr>(E))
+ return false;
+
+ if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
+ if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
+ if (FD->isBitField()) {
+ Diag(OpLoc, diag::err_alignof_bitfield) << ExprRange;
+ return true;
+ }
+ // Other fields are ok.
+ return false;
+ }
+ }
+ return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false);
+}
+
/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and
/// the same for @c alignof and @c __alignof
/// Note that the ArgRange is invalid if isType is false.
@@ -1060,7 +1081,13 @@
ArgTy = ArgEx->getType();
// Verify that the operand is valid.
- if (CheckSizeOfAlignOfOperand(ArgTy, OpLoc, Range, isSizeof)) {
+ bool isInvalid;
+ if (isSizeof)
+ isInvalid = CheckSizeOfAlignOfOperand(ArgTy, OpLoc, Range, true);
+ else
+ isInvalid = CheckAlignOfExpr(ArgEx, OpLoc, Range);
+
+ if (isInvalid) {
DeleteExpr(ArgEx);
return ExprError();
}
diff --git a/test/Sema/exprs.c b/test/Sema/exprs.c
index 73d73eb..5413757 100644
--- a/test/Sema/exprs.c
+++ b/test/Sema/exprs.c
@@ -45,3 +45,12 @@
__builtin_choose_expr (0, 42, i) = 10; // expected-warning {{extension used}}
return i;
}
+
+
+// PR3386
+struct f { int x : 4; float y[]; };
+int test9(struct f *P) {
+ return __alignof(P->x) + // expected-error {{invalid application of '__alignof' to bitfield}} expected-warning {{extension used}}
+ __alignof(P->y); // ok. expected-warning {{extension used}}
+}
+