Error handling cleanup in expr_initializer.cpp (and implied changes)

Author: danpoe

src/ansi-c/ansi_c_entry_point.cpp

@@ -177,8 +177,7 @@ bool ansi_c_entry_point(
     return false; // give up
   }
 
-  if(static_lifetime_init(symbol_table, symbol.location, message_handler))
-    return true;
+  static_lifetime_init(symbol_table, symbol.location, message_handler);
 
   return generate_ansi_c_start_function(symbol, symbol_table, message_handler);
 }

src/linking/static_lifetime_init.cpp

@@ -22,17 +22,16 @@ Author: Daniel Kroening, [email protected]
 
 #include <goto-programs/goto_functions.h>
 
-bool static_lifetime_init(
+void static_lifetime_init(
   symbol_tablet &symbol_table,
   const source_locationt &source_location,
   message_handlert &message_handler)
 {
-  namespacet ns(symbol_table);
+  PRECONDITION(symbol_table.has_symbol(INITIALIZE_FUNCTION));
 
-  const auto maybe_symbol=symbol_table.get_writeable(INITIALIZE_FUNCTION);
-  if(!maybe_symbol)
-    return false;
-  symbolt &init_symbol=*maybe_symbol;
+  const namespacet ns(symbol_table);
+
+  symbolt &init_symbol = symbol_table.get_writeable_ref(INITIALIZE_FUNCTION);
 
   init_symbol.value=code_blockt();
   init_symbol.value.add_source_location()=source_location;
@@ -117,16 +116,10 @@ bool static_lifetime_init(
 
     if(symbol.value.is_nil())
     {
-      try
-      {
-        namespacet ns(symbol_table);
-        rhs=zero_initializer(symbol.type, symbol.location, ns, message_handler);
-        assert(rhs.is_not_nil());
-      }
-      catch(...)
-      {
-        return true;
-      }
+      const namespacet ns(symbol_table);
+      rhs = zero_initializer(symbol.type, symbol.location, ns, message_handler);
+      INVARIANT(
+        rhs.is_not_nil(), "result of zero-initialization must be non-nil");
     }
     else
       rhs=symbol.value;
@@ -156,6 +149,4 @@ bool static_lifetime_init(
       dest.move_to_operands(function_call);
     }
   }
-
-  return false;
 }

src/linking/static_lifetime_init.h

@@ -16,7 +16,7 @@ class message_handlert;
 class source_locationt;
 class symbol_tablet;
 
-bool static_lifetime_init(
+void static_lifetime_init(
   symbol_tablet &symbol_table,
   const source_locationt &source_location,
   message_handlert &message_handler);

src/util/expr_initializer.cpp

@@ -123,12 +123,6 @@ exprt expr_initializert<nondet>::expr_initializer_rec(
     result.add_source_location()=source_location;
     return result;
   }
-  else if(type_id==ID_code)
-  {
-    error().source_location=source_location;
-    error() << "cannot initialize code-type" << eom;
-    throw 0;
-  }
   else if(type_id==ID_array)
   {
     const array_typet &array_type=to_array_type(type);
@@ -369,35 +363,17 @@ exprt zero_initializer(
   const source_locationt &source_location,
   const namespacet &ns)
 {
-  std::ostringstream oss;
-  stream_message_handlert mh(oss);
-
-  try
-  {
-    expr_initializert<false> z_i(ns, mh);
-    return z_i(type, source_location);
-  }
-  catch(int)
-  {
-    throw oss.str();
-  }
+  null_message_handlert null_message_handler;
+  expr_initializert<false> z_i(ns, null_message_handler);
+  return z_i(type, source_location);
 }
 
 exprt nondet_initializer(
   const typet &type,
   const source_locationt &source_location,
   const namespacet &ns)
 {
-  std::ostringstream oss;
-  stream_message_handlert mh(oss);
-
-  try
-  {
-    expr_initializert<true> z_i(ns, mh);
-    return z_i(type, source_location);
-  }
-  catch(int)
-  {
-    throw oss.str();
-  }
+  null_message_handlert null_message_handler;
+  expr_initializert<true> z_i(ns, null_message_handler);
+  return z_i(type, source_location);
 }