[Bug c++/12751] New: [tree-ssa] wrong code: double destruction

[Bug c++/12751] New: [tree-ssa] wrong code: double destruction

[stefaandr at hotmail dot com]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751

           Summary: [tree-ssa] wrong code: double destruction
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: stefaandr at hotmail dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu

I get the output: 
 Construct 
 Destruct 
 Destruct 
 
when running this code (sorry, couldn't get it smaller): 
#include <iostream> 
struct a { 
  a() { std::cout << "Construct" << std::endl; }; 
  ~a() { std::cout << "Destruct" << std::endl; }; 
}; 
int main() { 
  a a1; 
  std::string x; 
  switch(0) { 
    case 1: 
      { 
        a a2; 
        return 0; 
      } 
  }; 
}; 
 
Reading specs from /esat/firenze/install/lib/gcc/
i686-pc-linux-gnu/3.5-tree-ssa/specs 
Configured with: ../../gcc/ssa/configure --prefix=/esat/firenze/install 
--program-suffix=-ssa --enable-languages=c,c++ : (reconfigured)  : 
(reconfigured) 
Thread model: posix 
gcc version 3.5-tree-ssa 20031023 (merged 20031017) 
 /esat/firenze/install/libexec/gcc/i686-pc-linux-gnu/3.5-tree-ssa/cc1plus 
-quiet -v -D_GNU_SOURCE test6.cpp -quiet -dumpbase test6.cpp -mtune=pentiumpro 
-auxbase test6 -version -o /tmp/ccPznGwZ.s 
ignoring nonexistent directory "/esat/firenze/install/lib/gcc/
i686-pc-linux-gnu/3.5-tree-ssa/../../../../i686-pc-linux-gnu/include" 
#include "..." search starts here: 
#include <...> search starts here: 
 /esat/firenze/install/lib/gcc/i686-pc-linux-gnu/3.5-tree-ssa/../../../../
include/c++/3.5-tree-ssa 
 /esat/firenze/install/lib/gcc/i686-pc-linux-gnu/3.5-tree-ssa/../../../../
include/c++/3.5-tree-ssa/i686-pc-linux-gnu 
 /esat/firenze/install/lib/gcc/i686-pc-linux-gnu/3.5-tree-ssa/../../../../
include/c++/3.5-tree-ssa/backward 
 /usr/local/include 
 /esat/firenze/install/include 
 /esat/firenze/install/lib/gcc/i686-pc-linux-gnu/3.5-tree-ssa/include 
 /usr/include 
End of search list. 
GNU C++ version 3.5-tree-ssa 20031023 (merged 20031017) (i686-pc-linux-gnu) 
        compiled by GNU C version 3.3.1. 
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096 
 as -V -Qy -o /tmp/ccRkDD1N.o /tmp/ccPznGwZ.s 
GNU assembler version 2.14 (i686-pc-linux-gnu) using BFD version 2.14 20030612 
 /esat/firenze/install/libexec/gcc/i686-pc-linux-gnu/3.5-tree-ssa/collect2 
--eh-frame-hdr -m elf_i386 -dynamic-linker /lib/ld-linux.so.2 -o test6 /usr/
lib/crt1.o /usr/lib/crti.o /esat/firenze/install/lib/gcc/
i686-pc-linux-gnu/3.5-tree-ssa/crtbegin.o -L/esat/firenze/install/lib/gcc/
i686-pc-linux-gnu/3.5-tree-ssa -L/esat/firenze/install/lib/gcc/
i686-pc-linux-gnu/3.5-tree-ssa/../../.. /tmp/ccRkDD1N.o -lstdc++ -lm -lgcc_s 
-lgcc -lc -lgcc_s -lgcc /esat/firenze/install/lib/gcc/
i686-pc-linux-gnu/3.5-tree-ssa/crtend.o /usr/lib/crtn.o

[Bug c++/12751] [tree-ssa] wrong code: double destruction

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751



------- Additional Comments From pinskia at gcc dot gnu dot org  2003-10-24 00:32 -------
This looks like an eh problem because in gimple it looks right.

Here is a different example that uses printf instead of cout:
#include <string>

extern "C" int printf(const char*,...);
struct a {
  a() { printf("%p->a()\n");}
  ~a() { printf("%p->a()\n"); }
};
int main() {
  a a1;
  std::string x;
  switch(0) {
    case 1:
      {
        a a2;
        return 0;
      }
  };
};

0xbffffd18->a()
0xbffffba0->a()
0x0->a()

[Bug c++/12751] [tree-ssa] wrong code: double destruction

[bangerth at dealii dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751


bangerth at dealii dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2003-10-27 18:08:20
               date|                            |


------- Additional Comments From bangerth at dealii dot org  2003-10-27 18:08 -------
Andrew's code is close, but not quite valid. Here's a valid variant:
---------------------------------
#include <string>

extern "C" int printf(const char*,...);

struct a {
  a()  { printf("a::a\n");  }
  ~a() { printf("a::~a\n"); }
};

int main() {
  a a1;
  std::string x;
  switch(0) {
    case 1:
      {
        a a2;
        return 0;
      }
  };
};
-------------------------------------------
I can confirm the failure with a tree-ssa snapshot from 20031024.

W.

[Bug c++/12751] [tree-ssa] wrong code: double destruction

[bangerth at dealii dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751



------- Additional Comments From bangerth at dealii dot org  2003-10-27 22:40 -------
Just as Andrew mentioned there:
Most likely the same bug as PR 12789.

[Bug c++/12751] [tree-ssa] wrong code: double destruction

[bangerth at dealii dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751


bangerth at dealii dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical
           Keywords|                            |wrong-code
   Target Milestone|---                         |tree-ssa


------- Additional Comments From bangerth at dealii dot org  2003-10-27 22:33 -------
Here's a small, self-contained, testcase:
--------------------
extern int printf (__const char *__restrict __format, ...) throw ();

struct Y {
  Y() { printf("Y::Y\n");}
  ~Y() { printf("Y::~Y\n"); }
};

int main() {
  Y y1;
  Y y2;
  switch(0) {
    case 1:
      {
        Y y3;
        return 0;
      }
  };
};
---------------------------
When compiled with tree-ssa, I get this as output:
g/x> /home/bangerth/bin/gcc-tree-ssa/bin/c++ y.cc && ./a.out
Y::Y
Y::Y
Y::~Y
Y::~Y
Y::~Y

That is, two constructor, and three destructor calls (and no copy constructors
in between). That's definitely wrong.

W.

[Bug c++/12751] [tree-ssa] [eh] wrong code: double destruction

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[tree-ssa] wrong code:      |[tree-ssa] [eh] wrong code:
                   |double destruction          |double destruction


------- Additional Comments From pinskia at gcc dot gnu dot org  2003-10-27 22:42 -------
With printing out "this" (which is what my first attempt was going to do):
extern int printf (__const char *__restrict __format, ...) throw ();

struct Y {
  Y() { printf("Y(%p)::Y\n", this);}
  ~Y() { printf("Y(%p)::~Y\n", this); }
};

int main() {
  Y y1;
  Y y2;
  switch(0) {
    case 1:
      {
        Y y3;
        return 0;
      }
  };
};

You get:
Y(0xbffffd10)::Y
Y(0xbffffd20)::Y
Y(0xbffffd20)::~Y
Y(0xbffffd10)::~Y
Y(0xbffffd10)::~Y

Also note that gimple looks fine (but eh has too many labels/gotos to figure out what is going on).
Note -fno-exceptions also fixes the problem.

[Bug c++/12751] [tree-ssa] [eh] wrong code: double destruction

[rth at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751


rth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rth at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED


------- Additional Comments From rth at gcc dot gnu dot org  2003-10-30 01:46 -------
Mine.

[Bug c++/12751] [tree-ssa] [eh] wrong code: double destruction

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bangerth at dealii dot org


------- Additional Comments From pinskia at gcc dot gnu dot org  2003-10-30 04:53 -------
*** Bug 12789 has been marked as a duplicate of this bug. ***

[Bug c++/12751] [tree-ssa] [eh] wrong code: double destruction

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2003-11-14 07:55 -------
Subject: Bug 12751

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	tree-ssa-20020619-branch
Changes by:	rth@gcc.gnu.org	2003-11-14 07:55:11

Modified files:
	gcc            : ChangeLog.tree-ssa tree-eh.c 
Added files:
	gcc/testsuite/g++.dg/eh: dtor2.C 

Log message:
	PR c++/12751
	* tree-eh.c (struct leh_tf_state): Add outer.
	(lower_try_finally, lower_cleanup): Set it.
	(lower_try_finally_fallthru_label): New.
	(honor_protect_cleanup_actions): Use it.
	(lower_try_finally_copy, lower_try_finally_switch): Likewise.
	* g++.dg/eh/dtor2.C: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.tree-ssa.diff?cvsroot=gcc&only_with_tag=tree-ssa-20020619-branch&r1=1.1.2.862&r2=1.1.2.863
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-eh.c.diff?cvsroot=gcc&only_with_tag=tree-ssa-20020619-branch&r1=1.1.2.13&r2=1.1.2.14
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/eh/dtor2.C.diff?cvsroot=gcc&only_with_tag=tree-ssa-20020619-branch&r1=NONE&r2=1.1.2.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751

[Bug c++/12751] [tree-ssa] [eh] wrong code: double destruction

[rth at gcc dot gnu dot org]

------- Additional Comments From rth at gcc dot gnu dot org  2003-11-14 07:59 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12751