Hello,

The problem seems more related to Delphi, but I want to understand why it compiles only in FPC.

The declaration is just:

=== begin code ===
var
  FmtStr: function(const fmt: PAnsiChar): PAnsiChar; cdecl; varargs;
=== end code ===

And the full console project to test it in attachment.

It compiles only in FPC, in Delphi I got:

E2029 ',' or ':' expected but ';' found

Why? I don't know if it's a bug in Delphi or a breach in FPC.

ps. it compiles fine in FPC even using `$mode delphi`.

I believe in Delphi only external functions may use varargs. In your case you are declaring a variable, which could be assigned to a local function.

function FmtStr(const fmt: PAnsiChar): PAnsiChar; varargs; cdecl; external
yourlibname;

Note: varargs comes before cdecl, though I am not sure if it matters.

Anthony Walter wrote

I believe in Delphi only external functions may use varargs. In your case you are declaring a variable, which could be assigned to a local function.

You are right:

http://docwiki.embarcadero.com/RADStudio/XE8/en/E2591_Only_cdecl_functions_may_use_varargs_(Delphi)

http://docwiki.embarcadero.com/RADStudio/XE8/en/E2277_Only_external_cdecl_functions_may_use_varargs_(Delphi)

So it seems that I can't use `varargs` loading libraries dynamically on Delphi. :-(

function FmtStr(const fmt: PAnsiChar): PAnsiChar; varargs; cdecl; external

yourlibname;

I need to use it in variables because I wanna load my library dynamically. :-/

Note: varargs comes before cdecl, though I am not sure if it matters.

It seems irrelevant, but I saw it in some Delphi units declaring it as `... cdecl; varargs; ...`.

[...]

Fixed. I just removed the first `;`:

=== begin code ===
var
  FmtStr: function(const fmt: PAnsiChar): PAnsiChar; cdecl varargs;
=== end code ===

Now it compiles fine in an original copy of Delphi Seattle and in the FPC from trunk (3.1.1).

I'm glad to compile that, but it is very strange, according EMB docs:

"The varargs directive works only with external routines and only with the cdecl calling convention.":

http://docwiki.embarcadero.com/RADStudio/Seattle/en/Procedures_and_Functions#External_Declarations

But I saw many programmers using it in funcs declared as variable:

http://www.swissdelphicenter.ch/torry/showcode.php?id=2114 https://github.com/e-tobi/Delphi-Libxml2-XmlTextReader/blob/master/libxml2.pas

So I'm going to use it too hehe! :-)

silvioprog wrote

[...]

So I'm going to use it too hehe! :-)

Worked: http://pastebin.com/DjSkq7U8. :-)