[Bug plugins/62252] a callback to event PLUGIN_FINISH_TYPE segfaults

2014-08-25 Thread klemen.jan.enova at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62252

--- Comment #5 from klemen.jan.enova at gmail dot com ---
The build passed make check, but I said invoke_plugin_callback() should be
before cp_parser_set_decl_spec_type(), so I will try that way too.


[Bug plugins/62252] a callback to event PLUGIN_FINISH_TYPE segfaults

2014-08-25 Thread klemen.jan.enova at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62252

klemen.jan.enova at gmail dot com changed:

   What|Removed |Added

 CC||klemen.jan.enova at gmail dot 
com

--- Comment #4 from klemen.jan.enova at gmail dot com ---
Created attachment 33391
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33391&action=edit
cp-parser-patch

Fixes the bug. If I use debug_tree(type) in handle_struct(), it prints a
RECORD_TYPE only once, because the type declaration and definition happens only
once, other uses of the identifier "struct S" are variable declarations.


[Bug plugins/62252] a callback to event PLUGIN_FINISH_TYPE segfaults

2014-08-24 Thread klemen.jan.enova at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62252

--- Comment #3 from klemen.jan.enova at gmail dot com ---
It works on gcc, though.

in gcc/c/c-parser.c:

> if (!typespec_ok)
>   goto out;


> invoke_plugin_callbacks (PLUGIN_FINISH_TYPE, t.spec);
> declspecs_add_type (loc, specs, t);

in gcc/cp/parser.c:

>  type_spec = cp_parser_class_specifier (parser);
>  invoke_plugin_callbacks (PLUGIN_FINISH_TYPE, type_spec);
>  /* If that worked, we're done.  */
>  if (cp_parser_parse_definitely (parser))
>   {
> if (declares_class_or_enum)
>   *declares_class_or_enum = 2;
> if (decl_specs)
>   cp_parser_set_decl_spec_type (decl_specs,
> type_spec,
> token,
> /*type_definition_p=*/true);
> return type_spec;
>   }


I see a pattern. The call to invoke_plugin_callbacks() should probably be
before something_that_adds_the_type_to_decl_spec(). Also, there is a test in
both cases (typespec_ok VS cp_parser_parse_definitely). I will try to compile
gcc with this patch, and see what comes out.

[Bug plugins/62252] a callback to event PLUGIN_FINISH_TYPE segfaults

2014-08-24 Thread klemen.jan.enova at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62252

--- Comment #2 from klemen.jan.enova at gmail dot com ---
TREE_CODE(type) returns an ERROR_MARK. So, (tree) event_data must not alias
with a tree. This plugin is from
https://github.com/gcc-mirror/gcc/blob/master/gcc/testsuite/g%2B%2B.dg/plugin/dumb_plugin.c.
There are no checks there, it just assumes it is a type represented as a tree.


[Bug plugins/62252] New: a callback to event PLUGIN_FINISH_TYPE segfaults

2014-08-24 Thread klemen.jan.enova at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62252

Bug ID: 62252
   Summary: a callback to event PLUGIN_FINISH_TYPE segfaults
   Product: gcc
   Version: unknown
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: plugins
  Assignee: unassigned at gcc dot gnu.org
  Reporter: klemen.jan.enova at gmail dot com

The following plugin is a reduced version of
"testsuite/g++.dg/plugin/dumb_plugin.c".

I tested it with

- the ubuntu binary version of gcc-4.9
- ubuntu binary version of gcc-4.8 (g++-4.8 (Ubuntu 4.8.2-19ubuntu1) 4.8.2)
- the compiled version of gcc-4.9 taken from the 4.9 release
(https://github.com/gcc-mirror/gcc/releases/tag/gcc-4_9_0-release)

All tests segfault. 

---
kje@kje:~$ uname -a
Linux kje 3.13.0-34-generic #60-Ubuntu SMP Wed Aug 13 15:45:27 UTC 2014 x86_64
x86_64 x86_64 GNU/Linux
kje@kje:~/example$ cat example.c
#include "gcc-plugin.h"
//#include 
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tree.h"
#include "tree-pass.h"
#include "intl.h"
#include "toplev.h"
#include "diagnostic.h"
#include "context.h"

int plugin_is_GPL_compatible;

void
handle_struct (void *event_data, void *data)
{
tree type = (tree) event_data;
warning(0, G_("Process struct %s"),
IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type;
}

int
plugin_init (struct plugin_name_args *plugin_info,
 struct plugin_gcc_version *version)
{
  register_callback ("example", PLUGIN_FINISH_TYPE, handle_struct, NULL);

return 0;
}
kje@kje:~/example$ cat example_test.c
struct S {
int x;
};

int main(void)
{
struct S s;
s.x = 5;

return 0;
}
kje@kje:~/example$ g++-4.9 --version
g++-4.9 (Ubuntu 4.9.1-3ubuntu2~14.04.1) 4.9.1
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

kje@kje:~/example$ g++-4.9 -fPIC -g
-I/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.9.0/plugin/include -c example.c
kje@kje:~/example$ g++-4.9 -fPIC -g
-I/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.9.0/plugin/include -shared
example.o -o example_plugin.so
kje@kje:~/example$ g++-4.9 -fplugin=./example_plugin.so example_test.c
example_test.c:3:1: warning: Process struct S
 };
 ^
*** WARNING *** there are active plugins, do not report this as a bug unless
you can reproduce it without enabling any plugins.
Event| Plugins
PLUGIN_FINISH_TYPE   | example
example_test.c: In function ‘int main()’:
example_test.c:7:9: internal compiler error: Segmentation fault
  struct S s;
 ^
0x7f1d3226c780 handle_struct(void*, void*)
/home/kje/example/example.c:20
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See  for instructions.
The bug is not reproducible, so it is likely a hardware or OS problem.

---

If I use g++ compiled from (configure with --enable-languagues=c,c++) the
github repository 4.9 release, I get the whole call stack:

---

kje@kje:~/example$ g++ --version
g++ (GCC) 4.9.0
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

kje@kje:~/example$ g++ -fplugin=./example_plugin.so example_test.c
example_test.c:3:1: warning: Process struct S
 };
 ^
*** WARNING *** there are active plugins, do not report this as a bug unless
you can reproduce it without enabling any plugins.
Event| Plugins
PLUGIN_FINISH_TYPE   | example
example_test.c: In function ‘int main()’:
example_test.c:7:9: internal compiler error: Segmentation fault
  struct S s;
 ^
0x98cc2f crash_signal
../../../gcc4.9/gcc/toplev.c:337
0x7f520d010780 handle_struct(void*, void*)
/home/kje/example/example.c:20
0x8fb0b9 invoke_plugin_callbacks_full(int, void*)
../../../gcc4.9/gcc/plugin.c:542
0x5e82b5 invoke_plugin_callbacks
../../../gcc4.9/gcc/plugin.h:59
0x5e82b5 cp_parser_type_specifier
../../../gcc4.9/gcc/cp/parser.c:14338
0x5fdbb0 cp_parser_decl_specifier_seq
../../../gcc4.9/gcc/cp/parser.c:11573
0x602e79 cp_parser_simple_declaration
../../../gcc4.9/gcc/cp/parser.c:11163
0x5ea903 cp_parser_block_declaration
../../../gcc4.9/gcc/cp/parser.c:2
0x5eb961 cp_parser_declaration_statement
../../../gcc4.9/gcc/cp/parser.c:10759
0x5ebf9b cp_parser_statement
../../../gcc4.9/gcc/cp/parser.c:9492
0x5ecdc9 cp_parser_statement_seq_opt
../../../gcc4.9/gcc/cp/parser.c:9770
0x5ecf06 cp_parser_compound_statement
../../../gcc4.9/gcc/cp/parser.c:9724
0x5fb7d3 cp_parser_function_body
../../../gcc4.9/