Re: Custom types in target description XMLs

[Shahab Vahedi <shahab.vahedi@gmail.com>]

Hi Simon,

On Thu, Jul 15, 2021 at 10:37:39AM -0400, Simon Marchi wrote:
> Given the lack of response, I would say that nobody knows that off-hand,
> and you would need to dive into the code to check what is happening, if
> it's a GDB bug or something else.

I was just about to write another email. I have investigated both of the
problems and they seem like a bug to me.

The following change fixes the "field" type issue:

------------------------8<------------------------
diff --git a/gdb/valprint.c b/gdb/valprint.c
index 0749f38983e..91602b41274 100644
--- a/gdb/valprint.c
+++ b/gdb/valprint.c
@@ -1186,7 +1186,7 @@ val_print_type_code_flags (struct type *type, ...
 	    {
 	      unsigned field_len = TYPE_FIELD_BITSIZE (type, field);
 	      ULONGEST field_val
-		= val >> (TYPE_FIELD_BITPOS (type, field) - field_len + 1);
+		= val >> TYPE_FIELD_BITPOS (type, field);
 
 	      if (field_len < sizeof (ULONGEST) * TARGET_CHAR_BIT)
 		field_val &= ((ULONGEST) 1 << field_len) - 1;
------------------------>8------------------------

And this one solves the "struct" type problem:
------------------------8<------------------------
diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c
index 43c05d344d0..68e65ef8bb5 100644
--- a/gdb/gdbtypes.c
+++ b/gdb/gdbtypes.c
@@ -5805,7 +5805,7 @@ gdbtypes_post_init (struct gdbarch *gdbarch)
   builtin_type->builtin_string
     = arch_type (gdbarch, TYPE_CODE_STRING, TARGET_CHAR_BIT, "string");
   builtin_type->builtin_bool
-    = arch_type (gdbarch, TYPE_CODE_BOOL, TARGET_CHAR_BIT, "bool");
+    = arch_boolean_type (gdbarch, TARGET_CHAR_BIT, 1, "bool");
 
   /* The following three are about decimal floating point types, which
      are 32-bits, 64-bits and 128-bits respectively.  */
------------------------>8------------------------

I will file two separate bugs and then submit the two patches with the
explanations.


Cheers,
Shahab