Example #1
0
/// Finish - This does final analysis of the declspec, rejecting things like
/// "_Imaginary" (lacking an FP type).  This returns a diagnostic to issue or
/// diag::NUM_DIAGNOSTICS if there is no error.  After calling this method,
/// DeclSpec is guaranteed self-consistent, even if an error occurred.
void DeclSpec::Finish(Sema &S, const PrintingPolicy &Policy) {
  // Before possibly changing their values, save specs as written.
  SaveWrittenBuiltinSpecs();

  // Check the type specifier components first.

  // If decltype(auto) is used, no other type specifiers are permitted.
  if (TypeSpecType == TST_decltype_auto &&
      (TypeSpecWidth != TSW_unspecified ||
       TypeSpecComplex != TSC_unspecified ||
       TypeSpecSign != TSS_unspecified ||
       TypeAltiVecVector || TypeAltiVecPixel || TypeAltiVecBool ||
       TypeQualifiers)) {
    const unsigned NumLocs = 9;
    SourceLocation ExtraLocs[NumLocs] = {
      TSWLoc, TSCLoc, TSSLoc, AltiVecLoc,
      TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc, TQ_unalignedLoc
    };
    FixItHint Hints[NumLocs];
    SourceLocation FirstLoc;
    for (unsigned I = 0; I != NumLocs; ++I) {
      if (ExtraLocs[I].isValid()) {
        if (FirstLoc.isInvalid() ||
            S.getSourceManager().isBeforeInTranslationUnit(ExtraLocs[I],
                                                           FirstLoc))
          FirstLoc = ExtraLocs[I];
        Hints[I] = FixItHint::CreateRemoval(ExtraLocs[I]);
      }
    }
    TypeSpecWidth = TSW_unspecified;
    TypeSpecComplex = TSC_unspecified;
    TypeSpecSign = TSS_unspecified;
    TypeAltiVecVector = TypeAltiVecPixel = TypeAltiVecBool = false;
    TypeQualifiers = 0;
    S.Diag(TSTLoc, diag::err_decltype_auto_cannot_be_combined)
      << Hints[0] << Hints[1] << Hints[2] << Hints[3]
      << Hints[4] << Hints[5] << Hints[6] << Hints[7];
  }

  // Validate and finalize AltiVec vector declspec.
  if (TypeAltiVecVector) {
    if (TypeAltiVecBool) {
      // Sign specifiers are not allowed with vector bool. (PIM 2.1)
      if (TypeSpecSign != TSS_unspecified) {
        S.Diag(TSSLoc, diag::err_invalid_vector_bool_decl_spec)
          << getSpecifierName((TSS)TypeSpecSign);
      }

      // Only char/int are valid with vector bool. (PIM 2.1)
      if (((TypeSpecType != TST_unspecified) && (TypeSpecType != TST_char) &&
           (TypeSpecType != TST_int)) || TypeAltiVecPixel) {
        S.Diag(TSTLoc, diag::err_invalid_vector_bool_decl_spec)
          << (TypeAltiVecPixel ? "__pixel" :
                                 getSpecifierName((TST)TypeSpecType, Policy));
      }

      // Only 'short' and 'long long' are valid with vector bool. (PIM 2.1)
      if ((TypeSpecWidth != TSW_unspecified) && (TypeSpecWidth != TSW_short) &&
          (TypeSpecWidth != TSW_longlong))
        S.Diag(TSWLoc, diag::err_invalid_vector_bool_decl_spec)
          << getSpecifierName((TSW)TypeSpecWidth);

      // vector bool long long requires VSX support or ZVector.
      if ((TypeSpecWidth == TSW_longlong) &&
          (!S.Context.getTargetInfo().hasFeature("vsx")) &&
          (!S.Context.getTargetInfo().hasFeature("power8-vector")) &&
          !S.getLangOpts().ZVector)
        S.Diag(TSTLoc, diag::err_invalid_vector_long_long_decl_spec);

      // Elements of vector bool are interpreted as unsigned. (PIM 2.1)
      if ((TypeSpecType == TST_char) || (TypeSpecType == TST_int) ||
          (TypeSpecWidth != TSW_unspecified))
        TypeSpecSign = TSS_unsigned;
    } else if (TypeSpecType == TST_double) {
      // vector long double and vector long long double are never allowed.
      // vector double is OK for Power7 and later, and ZVector.
      if (TypeSpecWidth == TSW_long || TypeSpecWidth == TSW_longlong)
        S.Diag(TSWLoc, diag::err_invalid_vector_long_double_decl_spec);
      else if (!S.Context.getTargetInfo().hasFeature("vsx") &&
               !S.getLangOpts().ZVector)
        S.Diag(TSTLoc, diag::err_invalid_vector_double_decl_spec);
    } else if (TypeSpecType == TST_float) {
      // vector float is unsupported for ZVector.
      if (S.getLangOpts().ZVector)
        S.Diag(TSTLoc, diag::err_invalid_vector_float_decl_spec);
    } else if (TypeSpecWidth == TSW_long) {
      // vector long is unsupported for ZVector and deprecated for AltiVec.
      if (S.getLangOpts().ZVector)
        S.Diag(TSWLoc, diag::err_invalid_vector_long_decl_spec);
      else
        S.Diag(TSWLoc, diag::warn_vector_long_decl_spec_combination)
          << getSpecifierName((TST)TypeSpecType, Policy);
    }

    if (TypeAltiVecPixel) {
      //TODO: perform validation
      TypeSpecType = TST_int;
      TypeSpecSign = TSS_unsigned;
      TypeSpecWidth = TSW_short;
      TypeSpecOwned = false;
    }
  }

  // signed/unsigned are only valid with int/char/wchar_t.
  if (TypeSpecSign != TSS_unspecified) {
    if (TypeSpecType == TST_unspecified)
      TypeSpecType = TST_int; // unsigned -> unsigned int, signed -> signed int.
    else if (TypeSpecType != TST_int  && TypeSpecType != TST_int128 &&
             TypeSpecType != TST_char && TypeSpecType != TST_wchar) {
      S.Diag(TSSLoc, diag::err_invalid_sign_spec)
        << getSpecifierName((TST)TypeSpecType, Policy);
      // signed double -> double.
      TypeSpecSign = TSS_unspecified;
    }
  }

  // Validate the width of the type.
  switch (TypeSpecWidth) {
  case TSW_unspecified: break;
  case TSW_short:    // short int
  case TSW_longlong: // long long int
    if (TypeSpecType == TST_unspecified)
      TypeSpecType = TST_int; // short -> short int, long long -> long long int.
    else if (TypeSpecType != TST_int) {
      S.Diag(TSWLoc, diag::err_invalid_width_spec) << (int)TypeSpecWidth
        <<  getSpecifierName((TST)TypeSpecType, Policy);
      TypeSpecType = TST_int;
      TypeSpecOwned = false;
    }
    break;
  case TSW_long:  // long double, long int
    if (TypeSpecType == TST_unspecified)
      TypeSpecType = TST_int;  // long -> long int.
    else if (TypeSpecType != TST_int && TypeSpecType != TST_double) {
      S.Diag(TSWLoc, diag::err_invalid_width_spec) << (int)TypeSpecWidth
        << getSpecifierName((TST)TypeSpecType, Policy);
      TypeSpecType = TST_int;
      TypeSpecOwned = false;
    }
    break;
  }

  // TODO: if the implementation does not implement _Complex or _Imaginary,
  // disallow their use.  Need information about the backend.
  if (TypeSpecComplex != TSC_unspecified) {
    if (TypeSpecType == TST_unspecified) {
      S.Diag(TSCLoc, diag::ext_plain_complex)
        << FixItHint::CreateInsertion(
                              S.getLocForEndOfToken(getTypeSpecComplexLoc()),
                                                 " double");
      TypeSpecType = TST_double;   // _Complex -> _Complex double.
    } else if (TypeSpecType == TST_int || TypeSpecType == TST_char) {
      // Note that this intentionally doesn't include _Complex _Bool.
      if (!S.getLangOpts().CPlusPlus)
        S.Diag(TSTLoc, diag::ext_integer_complex);
    } else if (TypeSpecType != TST_float && TypeSpecType != TST_double) {
      S.Diag(TSCLoc, diag::err_invalid_complex_spec)
        << getSpecifierName((TST)TypeSpecType, Policy);
      TypeSpecComplex = TSC_unspecified;
    }
  }

  // C11 6.7.1/3, C++11 [dcl.stc]p1, GNU TLS: __thread, thread_local and
  // _Thread_local can only appear with the 'static' and 'extern' storage class
  // specifiers. We also allow __private_extern__ as an extension.
  if (ThreadStorageClassSpec != TSCS_unspecified) {
    switch (StorageClassSpec) {
    case SCS_unspecified:
    case SCS_extern:
    case SCS_private_extern:
    case SCS_static:
      break;
    default:
      if (S.getSourceManager().isBeforeInTranslationUnit(
            getThreadStorageClassSpecLoc(), getStorageClassSpecLoc()))
        S.Diag(getStorageClassSpecLoc(),
             diag::err_invalid_decl_spec_combination)
          << DeclSpec::getSpecifierName(getThreadStorageClassSpec())
          << SourceRange(getThreadStorageClassSpecLoc());
      else
        S.Diag(getThreadStorageClassSpecLoc(),
             diag::err_invalid_decl_spec_combination)
          << DeclSpec::getSpecifierName(getStorageClassSpec())
          << SourceRange(getStorageClassSpecLoc());
      // Discard the thread storage class specifier to recover.
      ThreadStorageClassSpec = TSCS_unspecified;
      ThreadStorageClassSpecLoc = SourceLocation();
    }
  }

  // If no type specifier was provided and we're parsing a language where
  // the type specifier is not optional, but we got 'auto' as a storage
  // class specifier, then assume this is an attempt to use C++0x's 'auto'
  // type specifier.
  if (S.getLangOpts().CPlusPlus &&
      TypeSpecType == TST_unspecified && StorageClassSpec == SCS_auto) {
    TypeSpecType = TST_auto;
    StorageClassSpec = SCS_unspecified;
    TSTLoc = TSTNameLoc = StorageClassSpecLoc;
    StorageClassSpecLoc = SourceLocation();
  }
  // Diagnose if we've recovered from an ill-formed 'auto' storage class
  // specifier in a pre-C++11 dialect of C++.
  if (!S.getLangOpts().CPlusPlus11 && TypeSpecType == TST_auto)
    S.Diag(TSTLoc, diag::ext_auto_type_specifier);
  if (S.getLangOpts().CPlusPlus && !S.getLangOpts().CPlusPlus11 &&
      StorageClassSpec == SCS_auto)
    S.Diag(StorageClassSpecLoc, diag::warn_auto_storage_class)
      << FixItHint::CreateRemoval(StorageClassSpecLoc);
  if (TypeSpecType == TST_char16 || TypeSpecType == TST_char32)
    S.Diag(TSTLoc, diag::warn_cxx98_compat_unicode_type)
      << (TypeSpecType == TST_char16 ? "char16_t" : "char32_t");
  if (Constexpr_specified)
    S.Diag(ConstexprLoc, diag::warn_cxx98_compat_constexpr);

  // C++ [class.friend]p6:
  //   No storage-class-specifier shall appear in the decl-specifier-seq
  //   of a friend declaration.
  if (isFriendSpecified() &&
      (getStorageClassSpec() || getThreadStorageClassSpec())) {
    SmallString<32> SpecName;
    SourceLocation SCLoc;
    FixItHint StorageHint, ThreadHint;

    if (DeclSpec::SCS SC = getStorageClassSpec()) {
      SpecName = getSpecifierName(SC);
      SCLoc = getStorageClassSpecLoc();
      StorageHint = FixItHint::CreateRemoval(SCLoc);
    }

    if (DeclSpec::TSCS TSC = getThreadStorageClassSpec()) {
      if (!SpecName.empty()) SpecName += " ";
      SpecName += getSpecifierName(TSC);
      SCLoc = getThreadStorageClassSpecLoc();
      ThreadHint = FixItHint::CreateRemoval(SCLoc);
    }

    S.Diag(SCLoc, diag::err_friend_decl_spec)
      << SpecName << StorageHint << ThreadHint;

    ClearStorageClassSpecs();
  }

  // C++11 [dcl.fct.spec]p5:
  //   The virtual specifier shall be used only in the initial
  //   declaration of a non-static class member function;
  // C++11 [dcl.fct.spec]p6:
  //   The explicit specifier shall be used only in the declaration of
  //   a constructor or conversion function within its class
  //   definition;
  if (isFriendSpecified() && (isVirtualSpecified() || isExplicitSpecified())) {
    StringRef Keyword;
    SourceLocation SCLoc;

    if (isVirtualSpecified()) {
      Keyword = "virtual";
      SCLoc = getVirtualSpecLoc();
    } else {
      Keyword = "explicit";
      SCLoc = getExplicitSpecLoc();
    }

    FixItHint Hint = FixItHint::CreateRemoval(SCLoc);
    S.Diag(SCLoc, diag::err_friend_decl_spec)
      << Keyword << Hint;

    FS_virtual_specified = FS_explicit_specified = false;
    FS_virtualLoc = FS_explicitLoc = SourceLocation();
  }

  assert(!TypeSpecOwned || isDeclRep((TST) TypeSpecType));

  // Okay, now we can infer the real type.

  // TODO: return "auto function" and other bad things based on the real type.

  // 'data definition has no type or storage class'?
}