[Bug tree-optimization/39202] New: internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[Bug tree-optimization/39202] New: internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[holger dot hopp at sap dot com]

testcase produces
internal compiler error: in collapse_rest_of_var, at
tree-ssa-structalias.c:3296

Version: trunk rev. 144201.
Reproduce: gcc-4.4 -O2 -c tst.c


typedef struct
{
  union
  {
    int * aaa;
  } u;
} t_a;

typedef struct
{
  unsigned bbb : 1;
} t_b;

typedef struct
{
  int ccc;
  t_a ddd;
  t_b eee;
  int fff;
} t_c;

typedef struct t_d
{
  t_c f1;
  t_c f2;
} t_d;

void foo (void)
{
  t_d ggg;
  ggg.f1 = ggg.f2;
}


-- 
           Summary: internal compiler error: in collapse_rest_of_var, at
                    tree-ssa-structalias.c:3296
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: holger dot hopp at sap dot com
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[dominiq at lps dot ens dot fr]

------- Comment #1 from dominiq at lps dot ens dot fr  2009-02-16 15:39 -------
Confirmed on i686-apple-darwin9 with '-m64 -O2', works with '-m32 -O2' or '-m64
-O1'. This is a regression as the code compiles with 4.2.3 or 4.3.3 and '-m64
-O2'.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[hjl dot tools at gmail dot com]

-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-02-16 15:49:32
               date|                            |
            Summary|internal compiler error: in |[4.4 Regression] internal
                   |collapse_rest_of_var, at    |compiler error: in
                   |tree-ssa-structalias.c:3296 |collapse_rest_of_var, at
                   |                            |tree-ssa-structalias.c:3296
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[hjl dot tools at gmail dot com]

------- Comment #2 from hjl dot tools at gmail dot com  2009-02-16 16:49 -------
This is caused by revision 137530:

http://gcc.gnu.org/ml/gcc-cvs/2008-07/msg00237.html


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenther at suse dot de


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[mmitchel at gcc dot gnu dot org]

-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2009-02-17 08:08 -------
In
              lhs.var = collapse_rest_of_var (lhs.var);
              rhs.var = collapse_rest_of_var (rhs.var);
rhs.var points into the middle of lhs.var chain, so the first call sets
collapsed_to to lhs.var and the second finds it already non-0.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2009-02-17 10:42 -------
I will have a look.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2009-02-16 15:49:32         |2009-02-17 10:42:05
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[rguenth at gcc dot gnu dot org]

------- Comment #5 from rguenth at gcc dot gnu dot org  2009-02-17 14:54 -------
This is because we merged ggg.f1.fff and ggg.f2.ccc into a single non-pointer
field.  In the end we should fix the structure copy constraint generation
more properly, but I have a patch that keeps collapse_rest_of_var and fixes
the problem.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[rguenth at gcc dot gnu dot org]

------- Comment #6 from rguenth at gcc dot gnu dot org  2009-02-17 16:02 -------
Subject: Bug 39202

Author: rguenth
Date: Tue Feb 17 16:01:53 2009
New Revision: 144235

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=144235
Log:
2009-02-17  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/39202
        * tree-ssa-structalias.c (do_structure_copy): Before collapsing
        a var make sure to follow existing collapses.

        * gcc.c-torture/compile/pr39202.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.c-torture/compile/pr39202.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-structalias.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202

[Bug tree-optimization/39202] [4.4 Regression] internal compiler error: in collapse_rest_of_var, at tree-ssa-structalias.c:3296

[rguenth at gcc dot gnu dot org]

------- Comment #7 from rguenth at gcc dot gnu dot org  2009-02-17 16:02 -------
Fixed.


-- 

rguenth at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39202