[Bug c/47650] New: wrong output of print_generic_decl() called from a plugin

[Bug c/47650] New: wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

           Summary: wrong output of print_generic_decl() called from a
                    plugin
           Product: gcc
           Version: 4.5.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: joe@mcknight.de


While testing how to parse C and C++ code for function prototypes from a plugin

(see http://gcc.gnu.org/ml/gcc/2010-12/msg00179.html)

I noticed that print_generic_decl() seems to output wrong data.

Consider the following function definition:

------------------
void barfunc (int foo, int abc, ... ) {

}
------------------

This outputs "static void barfunc (int);" but the function is neither
static nor does it expect only one int parameter...

Am I doing something wrong? I am calling "print_generic_decl(file,
decl, 0);" from the PLUGIN_PRE_GENERICIZE hook and this is gcc version
4.5.1 (GCC) on Solaris.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |middle-end

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-02-08 19:13:07 UTC ---
print_generic_decl is designed for debugging reasons only.  Any other use is a
bit bogus.  Also asking for help with plugins is not really a bug report but
should goto the gcc@ list.

[Bug c/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #1 from joe at mcknight dot de 2011-02-08 19:09:41 UTC ---
here's another example where print_generic_decl() fails:

-----------------------
typedef void (*Handler)( int , void * );
Handler GetFunctionPointer();
-----------------------

This would output "extern void (*Handler) (int, void *) GetFunctionPointer
(void);"

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #3 from joe at mcknight dot de 2011-02-08 20:08:51 UTC ---
(In reply to comment #2)
> print_generic_decl is designed for debugging reasons only.  Any other use is a
> bit bogus.  Also asking for help with plugins is not really a bug report but
> should goto the gcc@ list.

I am reporting the bug that print_generic_decl() is behaving incorrectly for
some kinds of declarations. This should either be fixed or a comment be placed
in the source code that warns about the usage of this function (and ideally
propose a better one).

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-02-08 20:10:43 UTC ---
(In reply to comment #3)
> I am reporting the bug that print_generic_decl() is behaving incorrectly for
> some kinds of declarations. This should either be fixed or a comment be placed
> in the source code that warns about the usage of this function (and ideally
> propose a better one).

Well I think you need to debug it to see why it is printing out static, it
might because a bit on tree has not been set yet.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #5 from joe at mcknight dot de 2011-02-08 20:16:28 UTC ---
(In reply to comment #4)
> Well I think you need to debug it to see why it is printing out static, it
> might because a bit on tree has not been set yet.

The static is a very minor issue. What is worse is that it doesn't see the
ellipsis and turns "void barfunc (int foo, int abc, ... )" into "void barfunc
(int)". It also outputs incorrect C when dealing with function pointers.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2011.02.09 10:40:36
         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

--- Comment #6 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-02-09 10:40:36 UTC ---
See http://gcc.gnu.org/ml/gcc-patches/2011-01/msg00956.html for a patch
(queued for 4.7, several tree-dump check testcases have to be adjusted).

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #7 from joe at mcknight dot de 2011-02-09 14:22:48 UTC ---
(In reply to comment #6)
> See http://gcc.gnu.org/ml/gcc-patches/2011-01/msg00956.html for a patch
> (queued for 4.7, several tree-dump check testcases have to be adjusted).

Cool, I can confirm that this fixes the example that I brought up in the
beginning! :-)

Now the remaining issue is wrong (non-C) output for function declarations with
function pointers.


Thanks!

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #8 from joe at mcknight dot de 2011-02-09 16:23:44 UTC ---
(In reply to comment #6)
> See http://gcc.gnu.org/ml/gcc-patches/2011-01/msg00956.html for a patch
> (queued for 4.7, several tree-dump check testcases have to be adjusted).

Richard, I've found another example for incorrect output of
print_generic_decl().

Here:

typedef struct {
  double dvar;
  int   ivar;
} *tpdefp;

int myfunc(tpdefp var);

The output would not treat the variable as being of the new type but it would
repeat the declaration of the struct in print_generic_decl() and output
(including newlines):

extern int myfunc (struct
{
  double dvar;
  int ivar;
} *);

That could be related to the function pointer issue where print_generic_decl()
also rather repeats the declaration instead of printing the new type.

Thanks.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #9 from rguenther at suse dot de <rguenther at suse dot de> 2011-02-09 16:33:30 UTC ---
On Wed, 9 Feb 2011, joe at mcknight dot de wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650
> 
> --- Comment #8 from joe at mcknight dot de 2011-02-09 16:23:44 UTC ---
> (In reply to comment #6)
> > See http://gcc.gnu.org/ml/gcc-patches/2011-01/msg00956.html for a patch
> > (queued for 4.7, several tree-dump check testcases have to be adjusted).
> 
> Richard, I've found another example for incorrect output of
> print_generic_decl().
> 
> Here:
> 
> typedef struct {
>   double dvar;
>   int   ivar;
> } *tpdefp;
> 
> int myfunc(tpdefp var);
> 
> The output would not treat the variable as being of the new type but it would
> repeat the declaration of the struct in print_generic_decl() and output
> (including newlines):
> 
> extern int myfunc (struct
> {
>   double dvar;
>   int ivar;
> } *);
> 
> That could be related to the function pointer issue where print_generic_decl()
> also rather repeats the declaration instead of printing the new type.

You should use a debugger to see why that happens, it should end up
printing TYPE_NAME which should be a TYPE_DECL with a DECL_NAME
which should be an IDENTIFIER_NODE.  You can also try TDF_SLIM.

Richard.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #10 from joe at mcknight dot de 2011-02-09 18:08:32 UTC ---
Created attachment 23285
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23285
A small test plugin that calls print_generic_decl()

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #11 from joe at mcknight dot de 2011-02-09 18:11:10 UTC ---
Created attachment 23286
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23286
A C file that provokes wrong output of print_generic_decl()

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #12 from joe at mcknight dot de 2011-02-09 18:14:36 UTC ---
> > That could be related to the function pointer issue where print_generic_decl()
> > also rather repeats the declaration instead of printing the new type.
> 
> You should use a debugger to see why that happens, it should end up
> printing TYPE_NAME which should be a TYPE_DECL with a DECL_NAME
> which should be an IDENTIFIER_NODE.  You can also try TDF_SLIM.

Unfortunately I'm not too experienced with debugging gcc... I tried TDF_SLIM
but this makes things rather worse than better. Instead I have added a small
testcase, a basic plugin that outputs a function declaration and a small .c
file containing functions that are incorrectly output by the plugin. I hope
this is of help for someone more knowledgeable in debugging gcc than me. If I
can provide any further help, please let me know.

Thanks.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #13 from joe at mcknight dot de 2011-02-10 22:50:51 UTC ---
(In reply to comment #6)
> See http://gcc.gnu.org/ml/gcc-patches/2011-01/msg00956.html for a patch
> (queued for 4.7, several tree-dump check testcases have to be adjusted).

Okay, this is a bit of voodoo now, but I am getting failures of this patch in
very special circumstances. I have narrowed it down to a small test program. If
I compile the following program with the previously posted testplugin:

typedef unsigned long size_t;
extern char *strncpy(char *restrict, const char *restrict, size_t);
char* strncpy0(char* dst, const char* src, size_t n) {
    return "abc";
}
char* strncat0(char* dst, const char* src, size_t n) {
    return "abc";
}

then I get the following output:

  static char * strncpy0 (char *, const char *, size_t, void, ...);
  static char * strncat0 (char *, const char *, size_t, void, ...);

meaning that the plugin is a bit over-enthusiastic about putting "...".

I am compiling on Solaris with:

gcc -O0 -fplugin=testplugin.so -std=gnu99 -m64 -S -o out.o out.c

(and this doesn't show up if I either drop the -std=gnu99 or the -m64. It also
doesn't show up if I drop the strncpy prototype from the example program. Nor
does it if I remove both restrict keywords, I can remove one "restrict"
however... Have I mentioned already that this reminds me a bit of voodoo?
:-)...)

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #14 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-15 13:39:50 UTC ---
Author: rguenth
Date: Tue Mar 15 13:39:28 2011
New Revision: 170995

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=170995
Log:
2011-03-15  Richard Guenther  <rguenther@suse.de>

    PR middle-end/47650
    * tree-pretty-print.c (dump_function_declaration): Properly
    dump unprototyped and varargs function types.

    * gfortran.dg/c_f_pointer_tests_3.f90: Adjust.
    * gfortran.dg/ishft_4.f90: Likewise.
    * gfortran.dg/leadz_trailz_3.f90: Likewise.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/c_f_pointer_tests_3.f90
    trunk/gcc/testsuite/gfortran.dg/ishft_4.f90
    trunk/gcc/testsuite/gfortran.dg/leadz_trailz_3.f90
    trunk/gcc/tree-pretty-print.c

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #15 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-15 13:41:02 UTC ---
Fixed.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #16 from joe at mcknight dot de 2011-03-15 15:52:01 UTC ---
Created attachment 23665
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23665
dump_function_declaration with debug

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #17 from joe at mcknight dot de 2011-03-15 15:53:23 UTC ---
Created attachment 23666
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23666
debug output from a run of the modified function

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #18 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-15 15:56:04 UTC ---
comment #13 would happen if the list of argument types is not terminated by
the shared tree node void_list_node but by a clone.  We expect the
shared void_list_node to be used elsewhere as well.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #19 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-15 15:59:44 UTC ---
All looks good to me with your C testcase:

gcc> gdb --args ./cc1 -quiet t.i
(gdb) b gimplify_function_tree
Breakpoint 5 at 0x855ac4: file /space/rguenther/src/svn/trunk/gcc/gimplify.c,
line 7820.
(gdb) run
Breakpoint 5, gimplify_function_tree (fndecl=0x7ffff5b49000)
    at /space/rguenther/src/svn/trunk/gcc/gimplify.c:7820
7820      gcc_assert (!gimple_body (fndecl));
(gdb) call debug_generic_expr (fndecl->common.type)
int <T357> (struct 
{
  double dvar;
  int ivar;
} *)
(gdb) call debug_generic_expr (fndecl)
myfunc
(gdb) c
Continuing.

Breakpoint 5, gimplify_function_tree (fndecl=0x7ffff5b29f00)
    at /space/rguenther/src/svn/trunk/gcc/gimplify.c:7820
7820      gcc_assert (!gimple_body (fndecl));
(gdb) call debug_generic_expr (fndecl)
GetFunctionPointer
(gdb) call debug_generic_expr (fndecl->common.type)
void (*Handler) (int, void *) <T352> (void)
(gdb) c
Continuing.

Breakpoint 3, 0x00007ffff63ca250 in exit () from /lib64/libc.so.6

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #20 from joe at mcknight dot de 2011-03-15 16:03:23 UTC ---
Unfortunately I cannot confirm that this bug is fixed, so I need to reopen it.

For one thing this bug is not only about variadic functions, but
dump_function_declaration() returns wrong output also for other cases as
described, like functions involving function pointers and typedef'ed structs.

Second I am still seeing the issue described earlier, where a function now
returns a variadic function even though there is none.

I have modified the function to print debug output to a file and I am attaching
both the modified function and its debug output. For me it looks like the "arg
!= void_list_node" does not work, so the while loop is executed once more,
printing the "void" and then arg goes NULL, the loop is left and since arg is
NULL, the function prints ", ..." at the end.

Let me know if there is anything else I can do to help.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #21 from joe at mcknight dot de 2011-03-15 16:18:37 UTC ---
(In reply to comment #19)
> All looks good to me with your C testcase:
> 
> (gdb) call debug_generic_expr (fndecl->common.type)
> int <T357> (struct 
> {
>   double dvar;
>   int ivar;
> } *)

Hm, the function was declared to take a new type "tpdefp", so I was expecting
the dump to return it like this and not resolve it to whatever it is typedef'ed
to.

Compare it to:

typedef int mytype;
int myfunc2(mytype var) {
    return 1;
};

which outputs

  static int myfunc2 (mytype);

i.e. returns the newly created type as well.


> (gdb) call debug_generic_expr (fndecl->common.type)
> void (*Handler) (int, void *) <T352> (void)

It outputs "static void (*Handler) (int, void *) GetFunctionPointer (void);"

And this is not C  :-)

The compiler throws a parse error when I compile a function with the prototype
that it outputs.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #22 from rguenther at suse dot de <rguenther at suse dot de> 2011-03-15 16:33:09 UTC ---
On Tue, 15 Mar 2011, joe at mcknight dot de wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650
> 
> --- Comment #21 from joe at mcknight dot de 2011-03-15 16:18:37 UTC ---
> (In reply to comment #19)
> > All looks good to me with your C testcase:
> > 
> > (gdb) call debug_generic_expr (fndecl->common.type)
> > int <T357> (struct 
> > {
> >   double dvar;
> >   int ivar;
> > } *)
> 
> Hm, the function was declared to take a new type "tpdefp", so I was expecting
> the dump to return it like this and not resolve it to whatever it is typedef'ed
> to.
> 
> Compare it to:
> 
> typedef int mytype;
> int myfunc2(mytype var) {
>     return 1;
> };
> 
> which outputs
> 
>   static int myfunc2 (mytype);
> 
> i.e. returns the newly created type as well.

That's by design.

> > (gdb) call debug_generic_expr (fndecl->common.type)
> > void (*Handler) (int, void *) <T352> (void)
> 
> It outputs "static void (*Handler) (int, void *) GetFunctionPointer (void);"
> 
> And this is not C  :-)
> 
> The compiler throws a parse error when I compile a function with the prototype
> that it outputs.

It's not designed to do that.  The functions are for debugging and
diagnostic output only, they are not supposed to generate valid C.

Richard.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #23 from joe at mcknight dot de 2011-03-15 17:05:24 UTC ---
(In reply to comment #22)
> > Compare it to:
> > 
> > typedef int mytype;
> > int myfunc2(mytype var) {
> >     return 1;
> > };
> > 
> > which outputs
> > 
> >   static int myfunc2 (mytype);
> > 
> > i.e. returns the newly created type as well.
> 
> That's by design.

Then what is the design rule behind it, for me it looks inconsistent to once
inline the original type and another time use the newly created type.


> > It outputs "static void (*Handler) (int, void *) GetFunctionPointer (void);"
> 
> It's not designed to do that.  The functions are for debugging and
> diagnostic output only, they are not supposed to generate valid C.

I know, but instead of creating a new language, wouldn't it be good to just
stick to the C grammar to describe what is being seen?



Was the debug output helpful with respect to the wrong variadic output?

thanks!

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #24 from rguenther at suse dot de <rguenther at suse dot de> 2011-03-16 09:38:37 UTC ---
On Tue, 15 Mar 2011, joe at mcknight dot de wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650
> 
> --- Comment #23 from joe at mcknight dot de 2011-03-15 17:05:24 UTC ---
> (In reply to comment #22)
> > > Compare it to:
> > > 
> > > typedef int mytype;
> > > int myfunc2(mytype var) {
> > >     return 1;
> > > };
> > > 
> > > which outputs
> > > 
> > >   static int myfunc2 (mytype);
> > > 
> > > i.e. returns the newly created type as well.
> > 
> > That's by design.
> 
> Then what is the design rule behind it, for me it looks inconsistent to once
> inline the original type and another time use the newly created type.
> 
> 
> > > It outputs "static void (*Handler) (int, void *) GetFunctionPointer (void);"
> > 
> > It's not designed to do that.  The functions are for debugging and
> > diagnostic output only, they are not supposed to generate valid C.
> 
> I know, but instead of creating a new language, wouldn't it be good to just
> stick to the C grammar to describe what is being seen?
> 
> 
> 
> Was the debug output helpful with respect to the wrong variadic output?

Well, it confirmed that void_list_node is not used, but I can't
reproduce this fact.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #25 from joe at mcknight dot de 2011-03-16 12:58:50 UTC ---
(In reply to comment #24)

> Well, it confirmed that void_list_node is not used, but I can't
> reproduce this fact.

Then how should we go on with this? As said, I can also only reproduce it under
very special circumstances but unfortunately these were the default
circumstances for our compiler runs.

Can we use anything else to terminate the loop? Is there any other debug output
that would be helpful for you?

Thanks!

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #26 from rguenther at suse dot de <rguenther at suse dot de> 2011-03-16 13:07:03 UTC ---
On Wed, 16 Mar 2011, joe at mcknight dot de wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650
> 
> --- Comment #25 from joe at mcknight dot de 2011-03-16 12:58:50 UTC ---
> (In reply to comment #24)
> 
> > Well, it confirmed that void_list_node is not used, but I can't
> > reproduce this fact.
> 
> Then how should we go on with this? As said, I can also only reproduce it under
> very special circumstances but unfortunately these were the default
> circumstances for our compiler runs.

You should try to debug this yourself then.

> Can we use anything else to terminate the loop? Is there any other debug output
> that would be helpful for you?

Well, try to figure out who creates that void_list_node clone.

You can use !VOID_TYPE_P (TREE_VALUE (arg)) instead.

Richard.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #27 from joe at mcknight dot de 2011-03-16 14:40:32 UTC ---
(In reply to comment #26)

> > Can we use anything else to terminate the loop? Is there any other debug output
> > that would be helpful for you?
> 
> Well, try to figure out who creates that void_list_node clone.
> 
> You can use !VOID_TYPE_P (TREE_VALUE (arg)) instead.

This works for that special case. Also checking for TREE_CHAIN(arg) != NULL
works.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

joe at mcknight dot de changed:

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

--- Comment #28 from joe at mcknight dot de 2011-03-17 20:03:59 UTC ---
Reopening, to document and keep track of the fact that at least one corner case
produces wrong output with the applied patch.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[joe at mcknight dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

--- Comment #29 from joe at mcknight dot de 2011-04-06 17:55:30 UTC ---
FWIW, I can reproduce this now on Solaris without any magic compiler switches:

The program is just this here:

-------------------
void
foo(char *buf, int bufsz);

void
foo(char * const buf, const int bufsz)
{
}
-------------------

Compiling with just

gcc -fplugin=/path/to/plugin/testplugin.so -c foo.c
(gcc 4.5.2 with your patch on sparc-sun-solaris2.10)

gives me:

  static void foo (char * const, int, void, ...);


However it only shows up on Solaris, I tried it on a Linux installation I have
as well and I get the correct output there :-(

Note the differences between the declaration and the definition regarding
"const". If I remove any const in the definition (for buf or bufsz) or add a
const to the declaration, the output will be correct.

[Bug middle-end/47650] wrong output of print_generic_decl() called from a plugin

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47650

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.7.0                       |---