SemaStmtAttr.cpp revision 053214013990ad8ec096dafc64aa7c0ad2b05bc0 
1//===--- SemaStmtAttr.cpp - Statement Attribute Handling ------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements stmt-related attribute processing.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Sema/SemaInternal.h"
15#include "TargetAttributesSema.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/Basic/SourceManager.h"
18#include "clang/Lex/Lexer.h"
19#include "clang/Sema/DelayedDiagnostic.h"
20#include "clang/Sema/Lookup.h"
21#include "clang/Sema/ScopeInfo.h"
22#include "llvm/ADT/StringExtras.h"
23
24using namespace clang;
25using namespace sema;
26
27static Attr *handleFallThroughAttr(Sema &S, Stmt *St, const AttributeList &A,
28                                   SourceRange Range) {
29  if (!isa<NullStmt>(St)) {
30    S.Diag(A.getRange().getBegin(), diag::err_fallthrough_attr_wrong_target)
31        << St->getLocStart();
32    if (isa<SwitchCase>(St)) {
33      SourceLocation L = Lexer::getLocForEndOfToken(Range.getEnd(), 0,
34                                  S.getSourceManager(), S.getLangOpts());
35      S.Diag(L, diag::note_fallthrough_insert_semi_fixit)
36          << FixItHint::CreateInsertion(L, ";");
37    }
38    return 0;
39  }
40  if (S.getCurFunction()->SwitchStack.empty()) {
41    S.Diag(A.getRange().getBegin(), diag::err_fallthrough_attr_outside_switch);
42    return 0;
43  }
44  return ::new (S.Context) FallThroughAttr(A.getRange(), S.Context);
45}
46
47
48static Attr *ProcessStmtAttribute(Sema &S, Stmt *St, const AttributeList &A,
49                                  SourceRange Range) {
50  switch (A.getKind()) {
51  case AttributeList::UnknownAttribute:
52    S.Diag(A.getLoc(), A.isDeclspecAttribute() ?
53           diag::warn_unhandled_ms_attribute_ignored :
54           diag::warn_unknown_attribute_ignored) << A.getName();
55    return 0;
56  case AttributeList::AT_FallThrough:
57    return handleFallThroughAttr(S, St, A, Range);
58  default:
59    // if we're here, then we parsed a known attribute, but didn't recognize
60    // it as a statement attribute => it is declaration attribute
61    S.Diag(A.getRange().getBegin(), diag::err_attribute_invalid_on_stmt)
62        << A.getName() << St->getLocStart();
63    return 0;
64  }
65}
66
67StmtResult Sema::ProcessStmtAttributes(Stmt *S, AttributeList *AttrList,
68                                       SourceRange Range) {
69  SmallVector<const Attr*, 8> Attrs;
70  for (const AttributeList* l = AttrList; l; l = l->getNext()) {
71    if (Attr *a = ProcessStmtAttribute(*this, S, *l, Range))
72      Attrs.push_back(a);
73  }
74
75  if (Attrs.empty())
76    return S;
77
78  return ActOnAttributedStmt(Range.getBegin(), Attrs, S);
79}
80