gcc-style asm aliases have multiple subtypes

The front-end generates ireps with multiple sub-ireps for gcc's __asm__
aliases.  This changes the use of .has_subtype() to checking whether there
is more than one.

Author: kroening

src/ansi-c/ansi_c_convert_type.cpp

@@ -45,9 +45,13 @@ void ansi_c_convert_typet::read_rec(const typet &type)
     c_qualifiers.is_volatile=true;
   else if(type.id()==ID_asm)
   {
-    if(type.has_subtype() &&
-       type.subtype().id()==ID_string_constant)
-      c_storage_spec.asm_label = to_string_constant(type.subtype()).get_value();
+    // These can have up to 5 subtypes; we only use the first one.
+    const auto &type_with_subtypes = to_type_with_subtypes(type);
+    if(
+      !type_with_subtypes.subtypes().empty() &&
+      type_with_subtypes.subtypes()[0].id() == ID_string_constant)
+      c_storage_spec.asm_label =
+        to_string_constant(type_with_subtypes.subtypes()[0]).get_value();
   }
   else if(type.id()==ID_section &&
           type.has_subtype() &&

src/ansi-c/c_storage_spec.cpp

@@ -52,11 +52,12 @@ void c_storage_spect::read(const typet &type)
   {
     alias = to_string_constant(type.subtype()).get_value();
   }
-  else if(type.id()==ID_asm &&
-          type.has_subtype() &&
-          type.subtype().id()==ID_string_constant)
+  else if(
+    type.id() == ID_asm && !to_type_with_subtypes(type).subtypes().empty() &&
+    to_type_with_subtypes(type).subtypes()[0].id() == ID_string_constant)
   {
-    asm_label = to_string_constant(type.subtype()).get_value();
+    asm_label =
+      to_string_constant(to_type_with_subtypes(type).subtypes()[0]).get_value();
   }
   else if(type.id()==ID_section &&
           type.has_subtype() &&