digitalmars.D.bugs - [Issue 1306] New: extern (Windows) should work like extern (C) for variables
- d-bugmail puremagic.com (28/28) Jul 02 2007 http://d.puremagic.com/issues/show_bug.cgi?id=1306
- d-bugmail puremagic.com (4/4) Jul 02 2007 http://d.puremagic.com/issues/show_bug.cgi?id=1306
- d-bugmail puremagic.com (23/23) Jul 02 2007 http://d.puremagic.com/issues/show_bug.cgi?id=1306
- d-bugmail puremagic.com (9/9) Jul 30 2007 http://d.puremagic.com/issues/show_bug.cgi?id=1306
http://d.puremagic.com/issues/show_bug.cgi?id=1306
Summary: extern (Windows) should work like extern (C) for
variables
Product: D
Version: 1.017
Platform: PC
OS/Version: Windows
Status: NEW
Keywords: link-failure
Severity: normal
Priority: P2
Component: DMD
AssignedTo: bugzilla digitalmars.com
ReportedBy: torhu yahoo.com
In some cases, extern (Windows) causes ' 0' to get added to the end of symbols
that represent variables. This causes linking errors. I wasn't able to create
a simple test case, but the problem should be clear.
Scenario:
I have a few hundred function pointers in a C library. To link with those, I
have to use extern (C). But to actually call the functions, I need the
function pointers to have type extern (Windows). Since extern (Windows)
changes the mangling of the pointers, I can't link both link with the C
library, and call the functions successfully. So I'm stuck, and probably need
some ugly workaround.
I compiled 'int __stdcall x;' with msvc 6, which it accepted with a warning.
Looking at the object file, the symbol was not affected by __stdcall. So DMD's
behavior is probably wrong.
--
Jul 02 2007
d-bugmail puremagic.com http://d.puremagic.com/issues/show_bug.cgi?id=1306 ------- Comment #1 from braddr puremagic.com 2007-07-02 10:33 ------- Please include a set of reproduction steps, including source code. --
Jul 02 2007
http://d.puremagic.com/issues/show_bug.cgi?id=1306
------- Comment #2 from torhu yahoo.com 2007-07-02 11:41 -------
I nailed, it's another problem with the export keyword.
stdcall.d:
---
export extern (Windows) void (*funcptr)(int);
void main()
{
funcptr(5);
}
---
Just to show how funcptr gets mangled:
c:\prog\test\D>dmd stdcall
c:\prog\dmd\bin\..\..\dm\bin\link.exe stdcall,,,user32+kernel32/noi;
OPTLINK (R) for Win32 Release 7.50B1
Copyright (C) Digital Mars 1989 - 2001 All Rights Reserved
c:\prog\dmd\bin\..\lib\phobos.lib(dmain2)
Error 42: Symbol Undefined _funcptr 0
--- errorlevel 1
funcptr is mangled as _funcptr 0, which I believe is a stdcall function of zero
arguments. This is clearly wrong, and won't link with the corresponding C
definition of the function pointer.
--
Jul 02 2007
http://d.puremagic.com/issues/show_bug.cgi?id=1306
bugzilla digitalmars.com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution| |FIXED
------- Comment #3 from bugzilla digitalmars.com 2007-07-30 15:48 -------
Fixed DMD 1.019 and 2.003
--
Jul 30 2007