void cpp_typecheckt::typecheck_class_template(
cpp_declarationt &declaration)
{
// Do template parameters. This also sets up the template scope.
cpp_scopet &template_scope=
typecheck_template_parameters(declaration.template_type());
typet &type=declaration.type();
template_typet &template_type=declaration.template_type();
bool has_body=type.find(ID_body).is_not_nil();
const cpp_namet &cpp_name=
static_cast<const cpp_namet &>(type.find(ID_tag));
if(cpp_name.is_nil())
{
err_location(type.source_location());
throw "class templates must not be anonymous";
}
if(!cpp_name.is_simple_name())
{
err_location(cpp_name.source_location());
throw "simple name expected as class template tag";
}
irep_idt base_name=cpp_name.get_base_name();
const cpp_template_args_non_tct &partial_specialization_args=
declaration.partial_specialization_args();
const irep_idt symbol_name=
class_template_identifier(
base_name, template_type, partial_specialization_args);
#if 0
// Check if the name is already used by a different template
// in the same scope.
{
cpp_scopet::id_sett id_set;
cpp_scopes.current_scope().lookup(
base_name,
cpp_scopet::SCOPE_ONLY,
cpp_scopet::TEMPLATE,
id_set);
if(!id_set.empty())
{
const symbolt &previous=lookup((*id_set.begin())->identifier);
if(previous.name!=symbol_name || id_set.size()>1)
{
err_location(cpp_name.source_location());
str << "template declaration of `" << base_name.c_str()
<< " does not match previous declaration\n";
str << "location of previous definition: " << previous.location;
throw 0;
}
}
}
#endif
// check if we have it already
symbol_tablet::symbolst::iterator previous_symbol=
symbol_table.symbols.find(symbol_name);
if(previous_symbol!=symbol_table.symbols.end())
{
// there already
cpp_declarationt &previous_declaration=
to_cpp_declaration(previous_symbol->second.type);
bool previous_has_body=
previous_declaration.type().find(ID_body).is_not_nil();
// check if we have 2 bodies
if(has_body && previous_has_body)
{
err_location(cpp_name.source_location());
str << "template struct `" << base_name
<< "' defined previously" << std::endl;
str << "location of previous definition: "
<< previous_symbol->second.location;
throw 0;
}
if(has_body)
{
// We replace the template!
// We have to retain any default parameters from the previous declaration.
salvage_default_arguments(
previous_declaration.template_type(),
declaration.template_type());
previous_symbol->second.type.swap(declaration);
#if 0
std::cout << "*****\n";
std::cout << *cpp_scopes.id_map[symbol_name];
std::cout << "*****\n";
std::cout << "II: " << symbol_name << std::endl;
#endif
// We also replace the template scope (the old one could be deleted).
cpp_scopes.id_map[symbol_name]=&template_scope;
// We also fix the parent scope in order to see the new
// template arguments
}
else
{
// just update any default arguments
salvage_default_arguments(
declaration.template_type(),
previous_declaration.template_type());
}
assert(cpp_scopes.id_map[symbol_name]->id_class == cpp_idt::TEMPLATE_SCOPE);
return;
}
// it's not there yet
symbolt symbol;
symbol.name=symbol_name;
symbol.base_name=base_name;
symbol.location=cpp_name.source_location();
symbol.mode=ID_cpp;
symbol.module=module;
symbol.type.swap(declaration);
symbol.is_macro=false;
symbol.value=exprt("template_decls");
symbol.pretty_name=
cpp_scopes.current_scope().prefix+id2string(symbol.base_name);
symbolt *new_symbol;
if(symbol_table.move(symbol, new_symbol))
throw "cpp_typecheckt::typecheck_compound_type: symbol_table.move() failed";
// put into current scope
cpp_idt &id=cpp_scopes.put_into_scope(*new_symbol);
id.id_class=cpp_idt::TEMPLATE;
id.prefix=cpp_scopes.current_scope().prefix+
id2string(new_symbol->base_name);
// link the template symbol with the template scope
cpp_scopes.id_map[symbol_name]=&template_scope;
assert(cpp_scopes.id_map[symbol_name]->id_class==cpp_idt::TEMPLATE_SCOPE);
}
void cpp_typecheckt::typecheck_function_template(
cpp_declarationt &declaration)
{
assert(declaration.declarators().size()==1);
cpp_declaratort &declarator=declaration.declarators()[0];
const cpp_namet &cpp_name=to_cpp_name(declarator.add(ID_name));
// do template arguments
// this also sets up the template scope
cpp_scopet &template_scope=
typecheck_template_parameters(declaration.template_type());
if(!cpp_name.is_simple_name())
{
err_location(declaration);
str << "function template must have simple name";
throw 0;
}
irep_idt base_name=cpp_name.get_base_name();
template_typet &template_type=declaration.template_type();
typet function_type=
declarator.merge_type(declaration.type());
cpp_convert_plain_type(function_type);
irep_idt symbol_name=
function_template_identifier(
base_name,
template_type,
function_type);
bool has_value=declarator.find(ID_value).is_not_nil();
// check if we have it already
symbol_tablet::symbolst::iterator previous_symbol=
symbol_table.symbols.find(symbol_name);
if(previous_symbol!=symbol_table.symbols.end())
{
bool previous_has_value =
to_cpp_declaration(previous_symbol->second.type).
declarators()[0].find(ID_value).is_not_nil();
if(has_value && previous_has_value)
{
err_location(cpp_name.source_location());
str << "function template symbol `" << base_name
<< "' declared previously" << std::endl;
str << "location of previous definition: "
<< previous_symbol->second.location;
throw 0;
}
if(has_value)
{
previous_symbol->second.type.swap(declaration);
cpp_scopes.id_map[symbol_name]=&template_scope;
}
// todo: the old template scope now is useless,
// and thus, we could delete it
return;
}
symbolt symbol;
symbol.name=symbol_name;
symbol.base_name=base_name;
symbol.location=cpp_name.source_location();
symbol.mode=ID_cpp;
symbol.module=module;
symbol.value.make_nil();
symbol.type.swap(declaration);
symbol.pretty_name=
cpp_scopes.current_scope().prefix+id2string(symbol.base_name);
symbolt *new_symbol;
if(symbol_table.move(symbol, new_symbol))
throw "cpp_typecheckt::typecheck_compound_type: symbol_table.move() failed";
// put into scope
cpp_idt &id=cpp_scopes.put_into_scope(*new_symbol);
id.id_class=cpp_idt::TEMPLATE;
id.prefix=cpp_scopes.current_scope().prefix+
id2string(new_symbol->base_name);
// link the template symbol with the template scope
assert(template_scope.id_class==cpp_idt::TEMPLATE_SCOPE);
cpp_scopes.id_map[symbol_name] = &template_scope;
}
void cpp_typecheckt::convert_class_template_specialization(
cpp_declarationt &declaration)
{
cpp_save_scopet saved_scope(cpp_scopes);
typet &type=declaration.type();
assert(type.id()==ID_struct);
cpp_namet &cpp_name=
static_cast<cpp_namet &>(type.add(ID_tag));
if(cpp_name.is_qualified())
{
err_location(cpp_name.source_location());
str << "qualifiers not expected here";
throw 0;
}
if(cpp_name.get_sub().size()!=2 ||
cpp_name.get_sub()[0].id()!=ID_name ||
cpp_name.get_sub()[1].id()!=ID_template_args)
{
// currently we are more restrictive
// than the standard
err_location(cpp_name.source_location());
str << "bad template-class-sepcialization name";
throw 0;
}
irep_idt base_name=
cpp_name.get_sub()[0].get(ID_identifier);
// copy the template arguments
const cpp_template_args_non_tct template_args_non_tc=
to_cpp_template_args_non_tc(cpp_name.get_sub()[1]);
// Remove the template arguments from the name.
cpp_name.get_sub().pop_back();
// get the template symbol
cpp_scopest::id_sett id_set;
cpp_scopes.current_scope().lookup(
base_name, cpp_scopet::SCOPE_ONLY, cpp_idt::TEMPLATE, id_set);
// remove any specializations
for(cpp_scopest::id_sett::iterator
it=id_set.begin();
it!=id_set.end();
) // no it++
{
cpp_scopest::id_sett::iterator next=it;
next++;
if(lookup((*it)->identifier).type.
find("specialization_of").is_not_nil())
id_set.erase(it);
it=next;
}
// only one should be left
if(id_set.empty())
{
err_location(type.source_location());
str << "class template `" << base_name << "' not found";
throw 0;
}
else if(id_set.size()>1)
{
err_location(type);
str << "class template `" << base_name << "' is ambiguous";
throw 0;
}
symbol_tablet::symbolst::iterator s_it=
symbol_table.symbols.find((*id_set.begin())->identifier);
assert(s_it!=symbol_table.symbols.end());
symbolt &template_symbol=s_it->second;
if(!template_symbol.type.get_bool(ID_is_template))
{
err_location(type);
str << "expected a template";
}
#if 0
// is this partial specialization?
if(declaration.template_type().parameters().empty())
{
// typecheck arguments -- these are for the 'primary' template!
cpp_template_args_tct template_args_tc=
typecheck_template_args(
declaration.source_location(),
to_cpp_declaration(template_symbol.type).template_type(),
template_args_non_tc);
// Full specialization, i.e., template<>.
// We instantiate.
instantiate_template(
cpp_name.source_location(),
template_symbol,
template_args_tc,
type);
}
else
#endif
{
// partial specialization -- we typecheck
declaration.partial_specialization_args()=template_args_non_tc;
declaration.set_specialization_of(template_symbol.name);
typecheck_class_template(declaration);
}
}
void cpp_typecheckt::convert_template_declaration(
cpp_declarationt &declaration)
{
assert(declaration.is_template());
if(declaration.member_spec().is_virtual())
{
err_location(declaration);
str << "invalid use of 'virtual' in template declaration";
throw 0;
}
if(declaration.is_typedef())
{
err_location(declaration);
str << "template declaration for typedef";
throw 0;
}
typet &type=declaration.type();
// there are
// 1) function templates
// 2) class templates
// 3) template members of class templates (static or methods)
// 4) variable templates (C++14)
if(declaration.is_class_template())
{
// there should not be declarators
if(!declaration.declarators().empty())
{
err_location(declaration);
throw "class template not expected to have declarators";
}
// it needs to be a class template
if(type.id()!=ID_struct)
{
err_location(declaration);
throw "expected class template";
}
// Is it class template specialization?
// We can tell if there are template arguments in the class name,
// like template<...> class tag<stuff> ...
if((static_cast<const cpp_namet &>(
type.find(ID_tag))).has_template_args())
{
convert_class_template_specialization(declaration);
return;
}
typecheck_class_template(declaration);
return;
}
else // maybe function template, maybe class template member, maye template variable
{
// there should be declarators in either case
if(declaration.declarators().empty())
{
err_location(declaration);
throw "non-class template is expected to have a declarator";
}
// Is it function template specialization?
// Only full specialization is allowed!
if(declaration.template_type().template_parameters().empty())
{
convert_template_function_or_member_specialization(declaration);
return;
}
// Explicit qualification is forbidden for function templates,
// which we can use to distinguish them.
assert(declaration.declarators().size()>=1);
cpp_declaratort &declarator=declaration.declarators()[0];
const cpp_namet &cpp_name=to_cpp_name(declarator.add(ID_name));
if(cpp_name.is_qualified() ||
cpp_name.has_template_args())
return typecheck_class_template_member(declaration);
// must be function template
typecheck_function_template(declaration);
return;
}
}
