[Bug fortran/34112] New: Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[Bug fortran/34112] New: Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

32bit Windows uses a different calling convention (called procedure pops the
stack, not caller) with a symbol name _<name>@n, where n is the number of bytes
to pop off.

See also:
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/19d77dfc75f8be58
http://gcc.gnu.org/ml/fortran/2007-11/msg00074.html

As the standard makes not provisions and !DEC$ (*DEC$, cDEC$) is widely used,
gfortran should accept the following:

  function CallWndRetProc(nCode, wParam, lParam)
  !DEC$ ATTRIBUTES STDCALL,DECORATE, ALIAS: 'CallWndRetProc' :: CallWndRetProc 
  end function

Documentation:
http://www.intel.com/software/products/compilers/docs/fmac/doc_files/source/extfile/lref_for/source_files/rfattcst.htm
http://www.intel.com/software/products/compilers/docs/fmac/doc_files/source/extfile/lref_for/source_files/rfattrib.htm

They seem to map to
(http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html):

STDCALL  ->  __attribute__(stdcall)
ALIAS    ->  __attribute__(alias("name"))
DECORATE -> ?

The problem with decorate is that its meaning depends on the platform. It may
decorate the "name" of alias with a "_" prefix and "@n" postfix or only with a
"_" prefix. Maybe one should start with STDCALL and ALIAS.

For alias one should do something as in c-pragma.c's apply_pragma_weak:

decl_attributes (&decl, build_tree_list (get_identifier ("alias"),
                                         build_tree_list (NULL, value)),
                 0);


-- 
           Summary: Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #1 from burnus at gcc dot gnu dot org  2007-11-15 19:25 -------
For stdcall and @n decoration, see also PR 31073.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[dannysmith at users dot sourceforge dot net]

------- Comment #2 from dannysmith at users dot sourceforge dot net  2007-11-16 23:09 -------
> The problem with decorate is that its meaning depends on the platform. It may
> decorate the "name" of alias with a "_" prefix and "@n" postfix or only with a
> "_" prefix. Maybe one should start with STDCALL and ALIAS.

Would the target hook TARGET_MANGLE_DECL_ASSEMBLER_NAME (see tm.texi, also
config/i386/winnt.c for implementation) help here?
Danny


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[tkoenig at gcc dot gnu dot org]

------- Comment #3 from tkoenig at gcc dot gnu dot org  2007-11-18 21:49 -------
This would be useful.


-- 

tkoenig at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2007-11-18 21:49:06
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[fxcoudert at gcc dot gnu dot org]

------- Comment #4 from fxcoudert at gcc dot gnu dot org  2008-02-05 10:17 -------
(In reply to comment #0)
> As the standard makes not provisions and !DEC$ (*DEC$, cDEC$) is widely used,
> gfortran should accept the following:
> 
>   function CallWndRetProc(nCode, wParam, lParam)
>   !DEC$ ATTRIBUTES STDCALL,DECORATE, ALIAS: 'CallWndRetProc' :: CallWndRetProc 
>   end function

I thought a bit about that recently, and I don't like the idea of having to
support parts of another vendor's extension. The first other idea I had was to
add that STDCALL specification as an extension to the BIND syntax:  
BIND(C,STDCALL). It is the logical place to put it, but it has to be protected
by macros to compile on other compilers, which is not very Fortran-ish.

So, my next idea is to provide an compile-time option that would make all
BIND(C) procedures in the compiled file STDCALL: true, this does not solve the
problem of existing code, and true, it requires creating different source files
if you want to use mixed calling conventions, but it seems like an good
alternative to satisfy our Windows power users and yet not add too much extra
kludge to the front-end.


-- 

fxcoudert at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |fxcoudert at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #5 from burnus at gcc dot gnu dot org  2008-02-05 15:12 -------
> I thought a bit about that recently, and I don't like the idea of having to
> support parts of another vendor's extension. The first other idea I had was to
> add that STDCALL specification as an extension to the BIND syntax:

If we don't follow !$DEC than I'm in favor of this variant, which one could
implement even if one implements !$DEC at some point.

> So, my next idea is to provide an compile-time option that would make all
> BIND(C) procedures in the compiled file STDCALL

I'm really against this; I think this is very confusing and makes it very hard
to combine STDCALL with non-STDCALL procedures.

#if defined __GFORTRAN__
  #define STDCALL  STDCALL
#else
  #define STDCALL  C
#endif

  subroutine my() bind(STDCALL,name="foo")

Or alternatively, though more difficult to CPP:

  subroutine my() bind(C,attribute="stdcall",name="foo")

where one could think of allowing other items from
http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #6 from burnus at gcc dot gnu dot org  2008-03-03 14:40 -------
Initial patch by Franc,ois-Xavier:
http://gcc.gnu.org/ml/fortran/2008-03/msg00007.html


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #7 from burnus at gcc dot gnu dot org  2008-03-04 22:20 -------
Intel documentation in PDF format:
http://softwarecommunity.intel.com/isn/downloads/softwareproducts/pdfs/347685.pdf
Directives (!DEC$) start at page 335


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #8 from burnus at gcc dot gnu dot org  2008-04-04 07:49 -------
It would be useful if one could support also

   !$GNU attributes align:16 :: variable name

or alike for calls to libraries which need alignment such as FFTW.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[fxcoudert at gcc dot gnu dot org]

------- Comment #9 from fxcoudert at gcc dot gnu dot org  2008-04-04 08:35 -------
(In reply to comment #8)
> It would be useful if one could support also
> 
>    !$GNU attributes align:16 :: variable name
> 
> or alike for calls to libraries which need alignment such as FFTW.

Yep, I think I mentioned that in my last c.l.f post about GNU attributes in
gfortran. And I also had the very same thought when I read this morning's c.l.f
thread :)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #10 from burnus at gcc dot gnu dot org  2009-06-16 14:22 -------
Add c.l.f link, mentioned in comment 9
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/7bbe1ee44c505be8/

Regarding TARGET_MANGLE_DECL_ASSEMBLER_NAME (comment 2):
Currently, the decorating (@<nn>) seems to be only done for ADA, cf.
a) config/i386/cygming.h:
  #define TARGET_MANGLE_DECL_ASSEMBLER_NAME i386_pe_mangle_decl_assembler_name
b) config/i386/winnt.c and there: i386_pe_maybe_mangle_decl_assembler_name

Need to check, when it is added and when not. (It should only be added when
"decorate" is specified.)


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2007-11-18 21:49:06         |2009-06-16 14:22:11
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #11 from burnus at gcc dot gnu dot org  2009-06-16 16:35 -------
Note information I got from Kai. (He was not 100% sure for some of the items
and I probably misunderstood also parts thus take with a grain of salt.)

With the stdcall attribute on Win32 the @<n> suffix is automatically added;
with fastcall a @ prefix is added and with cdecl a leading _ is added.
And with Win64 nothing is added (well, cdecl adds a leading _ but this is about
to change).

An alias does not automatically add the decoration thus the decoration
attribute might be useful. (Though, we don't need to support (weak) aliases
initially. For aliases, one needs in C a function prototype to get it working
properly. Thus one needs to check how to handle it correctly.)

Procedure pointers: Here, the calling method is also crucial, i.e. one needs to
be able (a) to specify it for proc pointers and (b) one needs to check it when
one does a proc pointer assignment.

DLLEXPORT/DLLIMPORT: Here, one also needs to handle global variables (= common,
module variables).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #12 from burnus at gcc dot gnu dot org  2009-06-28 17:57 -------
Subject: Bug 34112

Author: burnus
Date: Sun Jun 28 17:56:41 2009
New Revision: 149036

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=149036
Log:
2009-06-28  Tobias Burnus  <burnus@net-b.de>
            Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>

        PR fortran/34112
        * symbol.c (gfc_add_ext_attribute): New function.
        (gfc_get_sym_tree): New argument allow_subroutine.
        (gfc_get_symbol,gfc_get_ha_sym_tree,gen_cptr_param,gen_fptr_param
        gen_shape_param,generate_isocbinding_symbol): Use it.
        * decl.c (find_special): New argument allow_subroutine.
        (add_init_expr_to_sym,add_hidden_procptr_result,attr_decl1,
        match_procedure_in_type,gfc_match_final_decl): Use it.
        (gfc_match_gcc_attributes): New function.
        * gfortran.texi (Mixed-Language Programming): New section
        "GNU Fortran Compiler Directives".
        * gfortran.h (ext_attr_t): New struct.
        (symbol_attributes): Use it.
        (gfc_add_ext_attribute): New prototype.
        (gfc_get_sym_tree): Update pototype.
        * expr.c (gfc_check_pointer_assign): Check whether call
        convention is the same.
        * module.c (import_iso_c_binding_module, create_int_parameter,
        use_iso_fortran_env_module): Update gfc_get_sym_tree call.
        * scanner.c (skip_gcc_attribute): New function.
        (skip_free_comments,skip_fixed_comments): Use it.
        (gfc_next_char_literal): Support !GCC$ lines.
        * resolve.c (check_host_association): Update
        gfc_get_sym_tree call.
        * match.c (gfc_match_sym_tree,gfc_match_call): Update
        gfc_get_sym_tree call.
        * trans-decl.c (add_attributes_to_decl): New function.
        (gfc_get_symbol_decl,get_proc_pointer_decl,
        gfc_get_extern_function_decl,build_function_decl: Use it.
        * match.h (gfc_match_gcc_attributes): Add prototype.
        * parse.c (decode_gcc_attribute): New function.
        (next_free,next_fixed): Support !GCC$ lines.
        * primary.c (match_actual_arg,check_for_implicit_index,
        gfc_match_rvalue,gfc_match_rvalue): Update
        gfc_get_sym_tree call.

2009-06-28  Tobias Burnus  <burnus@net-b.de>

        PR fortran/34112
        * gfortran.dg/compiler-directive_1.f90: New test.
        * gfortran.dg/compiler-directive_2.f: New test.


Added:
    trunk/gcc/testsuite/gfortran.dg/compiler-directive_1.f90
    trunk/gcc/testsuite/gfortran.dg/compiler-directive_2.f
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/decl.c
    trunk/gcc/fortran/expr.c
    trunk/gcc/fortran/gfortran.h
    trunk/gcc/fortran/gfortran.texi
    trunk/gcc/fortran/match.c
    trunk/gcc/fortran/match.h
    trunk/gcc/fortran/module.c
    trunk/gcc/fortran/parse.c
    trunk/gcc/fortran/primary.c
    trunk/gcc/fortran/resolve.c
    trunk/gcc/fortran/scanner.c
    trunk/gcc/fortran/symbol.c
    trunk/gcc/fortran/trans-decl.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112

[Bug fortran/34112] Add $!DEC ATTRIBUTE support for 32bit Windows' STDCALL

[burnus at gcc dot gnu dot org]

------- Comment #13 from burnus at gcc dot gnu dot org  2009-06-28 19:51 -------
FIXED on the trunk (4.5).


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34112