Win32::API::Struct->sizeof() seems not to compute correctly struct size when nesting them:

use strict;
use warnings;

use Win32::API;

Win32::API::Struct->typedef('POINT', qw(
  LONG x;
  LONG y;
));

my $Point = Win32::API::Struct->new('POINT'); 
print "sizeof('POINT') = " . $Point->sizeof() . "\n";

Win32::API::Struct->typedef('CURSORINFO', qw(
  DWORD cbSize;
  DWORD flags;
  HANDLE hCursor;
  POINT ptScreenPos;
));

my $CursorInfo = Win32::API::Struct->new('CURSORINFO'); 
print "sizeof('CURSORINFO') = " . $CursorInfo->sizeof() . "\n";

Win32::API::Struct->typedef('MYSTRUCT', qw(
  DWORD cbSize;
  DWORD flags;
  HANDLE hCursor;
));

my $Struct = Win32::API::Struct->new('MYSTRUCT'); 
print "sizeof('MYSTRUCT') = " . $Struct->sizeof() . "\n";

__DATA__
sizeof('POINT') = 8
sizeof('CURSORINFO') = 16
sizeof('MYSTRUCT') = 12

[download]

8 + 12 != 16

Update: investigating a bit more, the problem seems linked with structure member alignment computations used in sizeof method (and require more knowledge than I've available for now :-)).

Bug discovered in v0.40 of Win32::API::Struct and reported as bug#6757 "Win32::API::Struct->sizeof() seems not to compute correctly struct size when nesting them".

____
HTH, Dominique
My two favorites:
If the only tool you have is a hammer, you will see every problem as a nail. --Abraham Maslow
Bien faire, et le faire savoir...

In reply to Re: Win32::API::Struct and GetCursorInfo with PCURSORINFO by dfaure
in thread Win32::API::Struct and GetCursorInfo with PCURSORINFO by EdwardG

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