RE: [PATCH v4 1/4] gdb, dwarf: add support for DW_AT_trampoline in DWARF reader

["Ijaz, Abdul B" <abdul.b.ijaz@intel.com>]

Hi Tom,

Thanks for the feedback.

Abdul> +	  if (target_name == NULL)
Tom> Probably your patch predates this but nowadays we're using nullptr instead of NULL.
Will fix in V5 patch.

Abdul> +		    (unsigned int) TYPE_FUNC_FLAGS (type));
Tom> If we're just printing the flags as an int, how about using hex instead?
Will update print format to hex in V5 patch.

Abdul> +    func_type_flags flags;
Tom>This should use ENUM_BITFIELD like the other spot in the patch.
This flag may store multiple values together with no return and trampoline types for a function. That is the reason why it is used like this here. So value is already bitfield like:
enum func_type_flag_value : unsigned
{
  FUNC_TYPE_NO_RETURN = (1 << 0),
  FUNC_TYPE_TRAMPOLINE = (1 << 1)
};

Thanks & Best Regards
Abdul Basit

-----Original Message-----
From: Tom Tromey <tom@tromey.com> 
Sent: Wednesday, August 2, 2023 10:08 PM
To: Abdul Basit Ijaz via Gdb-patches <gdb-patches@sourceware.org>
Cc: Ijaz, Abdul B <abdul.b.ijaz@intel.com>; JiniSusan.George@amd.com; tom@tromey.com; eliz@gnu.org; blarsen@redhat.com; Nils-Christian Kempke <nils-christian.kempke@intel.com>
Subject: Re: [PATCH v4 1/4] gdb, dwarf: add support for DW_AT_trampoline in DWARF reader

>>>>> "Abdul" == Abdul Basit Ijaz via Gdb-patches <gdb-patches@sourceware.org> writes:

Abdul> This patch adds support to GDB for reading the DW_AT_trampoline 
Abdul> attribute.  It stores the attribute and its value in the 
Abdul> type_specific part of a GDB type.  This patch is implemented in 
Abdul> preparation of the following patches, which will add a mechanism 
Abdul> to hide DW_AT_trampoline subroutines from the user.

Thanks for the patch.

Abdul> +	  if (target_name == NULL)
Abdul> +	    target_name = dwarf2_physname (NULL, target_die, 
Abdul> +target_cu);

Probably your patch predates this but nowadays we're using nullptr instead of NULL.

Abdul> +	  unrelocated_addr target_addr_reloc = attr->as_address ();
Abdul> +	  CORE_ADDR target_addr
Abdul> +	    = cu->per_objfile->relocate (target_addr_reloc);
Abdul> +	  target_addr = gdbarch_adjust_dwarf2_addr (objfile->arch (),
Abdul> +						    target_addr);

dwarf2_per_objfile::relocate already calls gdbarch_adjust_dwarf2_addr, so that call isn't needed.

Abdul> +	gdb_printf ("%*sfunc_type_flags %u\n", spaces, "",
Abdul> +		    (unsigned int) TYPE_FUNC_FLAGS (type));

If we're just printing the flags as an int, how about using hex instead?

Abdul> -    unsigned int is_noreturn : 1;
Abdul> +    func_type_flags flags;

This should use ENUM_BITFIELD like the other spot in the patch.

Tom
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