[Bug tree-optimization/25962] New: Pointer (null) check after the use

[Bug tree-optimization/25962] New: Pointer (null) check after the use

[uttamp at us dot ibm dot com]

In file gcc/cgraphunit.c, function verify_cgraph_node(struct cgraph_node
*node), the input argument 'node' has been dereferenced before doing any
checking till on line 717 with following codition,
...
717 if (!node)
718    {
719      error ("node not found in DECL_ASSEMBLER_NAME hash");
720      error_found = true;
721    }
...

Shouldn't this code be moved at the begining of this function? before
de-referencing it?

Also, on line 789-793, if there is any error, we call dump_cgraph_node(), which
dumps the cgraph node. Shouldn't we do a check for non-null 'node', either here
before calling or in function dump_cgraph_node() itself? This has been,
reported as a possible error by 'coverity prevent tool'.

Any thoughts?


-- 
           Summary: Pointer (null) check after the use
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: uttamp at us dot ibm dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug tree-optimization/25962] Pointer (null) check after the use

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2006-01-26 00:12 -------
I noticed something like this in a different place (but only because I actually
triped over it).

There is another way you can find stuff like this one, by looking at the vrp
tree dump :).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug tree-optimization/25962] Pointer (null) check after the use

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2006-01-26 11:06 -------
I believe the error is instead that

  for (main_clone = cgraph_node (node->decl); main_clone;
       main_clone = main_clone->next_clone)
    if (main_clone == node)
      break;
  if (!node)
    {
      error ("node not found in DECL_ASSEMBLER_NAME hash");
      error_found = true; 
    }

we should check main_clone here instead of node.  Checking node makes no
sense here.  Honza, can you confirm this?


-- 

rguenth at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug tree-optimization/25962] Pointer (null) check after the use

[pinskia at gcc dot gnu dot org]

------- Comment #3 from pinskia at gcc dot gnu dot org  2006-01-26 21:27 -------
Confirmed.


-- 

pinskia 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         |2006-01-26 21:27:52
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug middle-end/25962] Pointer (null) check after the use in cgraph.c

[hubicka at gcc dot gnu dot org]

------- Comment #4 from hubicka at gcc dot gnu dot org  2006-04-30 13:48 -------
testing patch.


-- 

hubicka at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug middle-end/25962] Pointer (null) check after the use in cgraph.c

[hubicka at gcc dot gnu dot org]

------- Comment #5 from hubicka at gcc dot gnu dot org  2006-05-04 12:43 -------
Subject: Bug 25962

Author: hubicka
Date: Thu May  4 12:42:55 2006
New Revision: 113522

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=113522
Log:
        PR middle-end/25962
        * cgraphunit.c (verify_cgraph_node): Fix cgraph_hash testing.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cgraphunit.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug middle-end/25962] Pointer (null) check after the use in cgraph.c

[pinskia at gcc dot gnu dot org]

------- Comment #6 from pinskia at gcc dot gnu dot org  2006-05-08 07:15 -------
Fixed.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.2.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962

[Bug middle-end/25962] Pointer (null) check after the use in cgraph.c

[hubicka at gcc dot gnu dot org]

------- Comment #7 from hubicka at gcc dot gnu dot org  2006-05-08 21:42 -------
Subject: Bug 25962

Author: hubicka
Date: Mon May  8 21:42:17 2006
New Revision: 113633

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=113633
Log:

        PR middle-end/25962
        * cgraphunit.c (decide_is_function_needed): When not optimizing even
        unused static functions are needed.

        * gcc.dg/pr25962.c: New.

Added:
    trunk/gcc/testsuite/gcc.dg/pr25962.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cgraphunit.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25962