Fix boolean to string conversion in expr2java

Fixes diffblue/test-gen#206.

Author: peterschrammel

src/java_bytecode/expr2java.cpp

@@ -195,9 +195,15 @@ std::string expr2javat::convert_constant(
   const constant_exprt &src,
   unsigned &precedence)
 {
-  if(src.type().id()==ID_bool)
+  if(src.type().id()==ID_c_bool)
+  {
+    if(!src.is_zero())
+      return "true";
+    else
+      return "false";
+  }
+  else if(src.type().id()==ID_bool)
   {
-    // Java has built-in Boolean constants, in contrast to C
     if(src.is_true())
       return "true";
     else if(src.is_false())
@@ -482,7 +488,6 @@ std::string expr2javat::convert(
   const exprt &src,
   unsigned &precedence)
 {
-  const typet &type=ns.follow(src.type());
   if(src.id()=="java-this")
     return convert_java_this(src, precedence=15);
   if(src.id()==ID_java_instanceof)
@@ -510,13 +515,8 @@ std::string expr2javat::convert(
   }
   else if(src.id()==ID_java_string_literal)
     return '"'+MetaString(src.get_string(ID_value))+'"';
-  else if(src.id()==ID_constant && (type.id()==ID_bool || type.id()==ID_c_bool))
-  {
-    if(src.is_true())
-      return "true";
-    else
-      return "false";
-  }
+  else if(src.id()==ID_constant)
+    return convert_constant(to_constant_expr(src), precedence=16);
   else
     return expr2ct::convert(src, precedence);
 }