[Bug go/54649] New: Go bootstrap failed

[Bug go/54649] New: Go bootstrap failed

[dehao at google dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

             Bug #: 54649
           Summary: Go bootstrap failed
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: go
        AssignedTo: ian@airs.com
        ReportedBy: dehao@google.com


In r191494, the bootstrap for go is broken.

Ian has a small testcase to reproduce this:

#include <string>

std::string
f(bool is_string, bool is_constant)
{
  if (is_string)
    {
      std::string left_string;
      std::string right_string;
      if (is_constant)
        {
          return left_string + right_string;
        }
    }

  return "";
}

When I compile that with current mainline with -O -g I get a crash
(the backtrace is a local patch of mine):

foo.cc: In function ‘std::string f(bool, bool)’:
foo.cc:17:1: internal compiler error: tree check: expected block, have
function_decl in change_scope, at final.c:1544
 }
 ^
0xe388bd tree_check_failed(tree_node const*, char const*, int, char const*,
...)
        ../../trunk/gcc/tree.c:8892
0x50c495 tree_check(tree_node*, char const*, int, char const*, tree_code)
        ../../trunk/gcc/tree.h:3659
0x9372a1 change_scope
        ../../trunk/gcc/final.c:1544
0x937646 reemit_insn_block_notes
        ../../trunk/gcc/final.c:1613
0x937822 final_start_function(rtx_def*, _IO_FILE*, int)
        ../../trunk/gcc/final.c:1670
0x93c6ad rest_of_handle_final
        ../../trunk/gcc/final.c:4291
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.

[Bug go/54649] Go bootstrap failed

[dehao at google dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

--- Comment #1 from Dehao Chen <dehao at google dot com> 2012-09-21 01:15:17 UTC ---
This problem is caused by the inconsistency between r191338 and r191494, both
of which handle the debug info.

The problem is that when we set the line number for stmts in the finally block,
we don't want to change its block info. Otherwise, we might set an empty block
to a call statement.

[Bug middle-end/54649] [4.8 Regression] Go bootstrap failed

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-09-21
          Component|go                          |middle-end
   Target Milestone|---                         |4.8.0
            Summary|Go bootstrap failed         |[4.8 Regression] Go
                   |                            |bootstrap failed
     Ever Confirmed|0                           |1

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-09-21 08:52:35 UTC ---
Confirmed.  We want at least the function scope here, thus DECL_INITIAL.

[Bug middle-end/54649] [4.8 Regression] Go bootstrap failed

[markus at trippelsdorf dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

Markus Trippelsdorf <markus at trippelsdorf dot de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |markus at trippelsdorf dot
                   |                            |de

--- Comment #3 from Markus Trippelsdorf <markus at trippelsdorf dot de> 2012-09-21 14:02:03 UTC ---
*** Bug 54655 has been marked as a duplicate of this bug. ***

[Bug middle-end/54649] [4.8 Regression] Go bootstrap failed

[dehao at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

--- Comment #4 from dehao at gcc dot gnu.org 2012-09-21 15:35:51 UTC ---
Author: dehao
Date: Fri Sep 21 15:35:46 2012
New Revision: 191614

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191614
Log:
2012-09-21  Dehao Chen  <dehao@google.com>

    PR go/54649
    * tree-eh.c (lower_try_finally_dup_block): Set the correct block for
    stmts in the duplicated EH block.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/tree-eh.c

[Bug middle-end/54649] [4.8 Regression] Go bootstrap failed

[dehao at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

--- Comment #5 from dehao at gcc dot gnu.org 2012-09-21 17:01:46 UTC ---
Author: dehao
Date: Fri Sep 21 17:01:36 2012
New Revision: 191615

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191615
Log:
2012-09-21  Dehao Chen  <dehao@google.com>

    PR go/54649
    PR tree-optimization/54655
    * g++.dg/pr54655.C: New testcase.


Added:
    trunk/gcc/testsuite/g++.dg/pr54655.C
Modified:
    trunk/gcc/testsuite/ChangeLog

[Bug middle-end/54649] [4.8 Regression] Go bootstrap failed

[dehao at google dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54649

Dehao Chen <dehao at google dot com> changed:

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

--- Comment #6 from Dehao Chen <dehao at google dot com> 2012-10-02 16:37:44 UTC ---
This bug has been fixed by:

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191614
Log:
2012-09-21  Dehao Chen  <dehao@google.com>

    PR go/54649
    * tree-eh.c (lower_try_finally_dup_block): Set the correct block for
    stmts in the duplicated EH block.