Clean-up irep-id emptyness checks in ansi-c

Author: peterschrammel

src/ansi-c/ansi_c_declaration.cpp

@@ -33,7 +33,7 @@ void ansi_c_declaratort::build(irept &src)
       t.make_nil();
       break;
     }
-    else if(t.id()==irep_idt() ||
+    else if(t.id().empty() ||
             t.is_nil())
     {
       assert(0);

src/ansi-c/c_typecheck_base.cpp

@@ -539,7 +539,7 @@ void c_typecheck_baset::typecheck_function_body(symbolt &symbol)
       p_it++)
   {
     // may be anonymous
-    if(p_it->get_base_name()==irep_idt())
+    if(p_it->get_base_name().empty())
     {
       irep_idt base_name="#anon"+std::to_string(anon_counter++);
       p_it->set_base_name(base_name);

src/ansi-c/c_typecheck_expr.cpp

@@ -1522,7 +1522,7 @@ void c_typecheck_baset::typecheck_expr_member(exprt &expr)
   // copy method identifier
   const irep_idt &identifier=component.get(ID_C_identifier);
 
-  if(identifier!=irep_idt())
+  if(!identifier.empty())
     expr.set(ID_C_identifier, identifier);
 
   const irep_idt &access=component.get_access();

src/ansi-c/c_typecheck_type.cpp

@@ -428,7 +428,7 @@ void c_typecheck_baset::typecheck_code_type(code_typet &type)
         irep_idt identifier=declaration.declarator().get_name();
 
         // abstract or not?
-        if(identifier==irep_idt())
+        if(identifier.empty())
         {
           // abstract
           parameter.add_source_location()=declaration.type().source_location();
@@ -550,7 +550,7 @@ void c_typecheck_baset::typecheck_array_type(array_typet &type)
     {
       // not a constant and not infinity
 
-      assert(current_symbol_id!=irep_idt());
+      assert(!current_symbol_id.empty());
 
       const symbolt &base_symbol=lookup(current_symbol_id);
 
@@ -862,7 +862,7 @@ void c_typecheck_baset::typecheck_compound_body(
   // scan for anonymous members, and name them
   for(auto &member : components)
   {
-    if(member.get_name()!=irep_idt())
+    if(!member.get_name().empty())
       continue;
 
     member.set_name("$anon"+std::to_string(anon_member_counter++));

src/ansi-c/type2name.cpp

@@ -110,7 +110,7 @@ static std::string type2name(
   if(!type.source_location().get_function().empty())
     result+='l';
 
-  if(type.id()==irep_idt())
+  if(type.id().empty())
     throw "empty type encountered";
   else if(type.id()==ID_empty)
     result+='V';