[Bug c/17723] New: [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[Bug c/17723] New: [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[martin at mpa-garching dot mpg dot de]

The attached testcase (sorry, no time to reduce its size) causes
current mainline to segfault:

>gcc -v -O2 -c bug.i
Reading specs from /afs/mpa/data/martin/ugcc/lib/gcc/i686-pc-linux-gnu/4.0.0/specs
Configured with: /scratch/gcc/configure --quiet
--prefix=/afs/mpa/data/martin/ugcc --enable-languages=c++,f95
--with-gmp=/afs/mpa/data/martin/mygmp
Thread model: posix
gcc version 4.0.0 20040929 (experimental)
 /afs/mpa/data/martin/ugcc/libexec/gcc/i686-pc-linux-gnu/4.0.0/cc1
-fpreprocessed bug.i -quiet -dumpbase bug.i -mtune=pentiumpro -auxbase bug -O2
-version -o /tmp/ccW802VQ.s
GNU C version 4.0.0 20040929 (experimental) (i686-pc-linux-gnu)
        compiled by GNU C version 4.0.0 20040929 (experimental).
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
eval.l: In function 'fflex':
eval.l:518: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

-- 
           Summary: [4.0.0 regression] [ICE on legal code] gcc segfaults
                    with -O2
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: martin at mpa-garching dot mpg dot de
                CC: gcc-bugs at gcc dot gnu dot org,martin at mpa-garching
                    dot mpg dot de
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug c/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[martin at mpa-garching dot mpg dot de]

------- Additional Comments From martin at mpa-garching dot mpg dot de  2004-09-29 13:06 -------
Created an attachment (id=7236)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=7236&action=view)
an (unfortunately large) testcase


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug c/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[martin at mpa-garching dot mpg dot de]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
      Known to fail|                            |4.0.0
      Known to work|                            |3.3.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-29 13:46 -------
I can reproduce but I have not reduced it yet. Here is the backtrace:
#0  0x08180098 in merge_memattrs (x=0xf695a0e4, y=0xf695a1a4) at /home/gates/pinskia/src/
gnu/gcc/src/gcc/cfgcleanup.c:956
#1  0x0817ffcd in merge_memattrs (x=0xf695a0f0, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#2  0x0817ffcd in merge_memattrs (x=0xf695a0d8, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#3  0x0817ffcd in merge_memattrs (x=0xf69b5ccc, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#4  0x0817ffcd in merge_memattrs (x=0xf69b5cd8, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#5  0x0817ffcd in merge_memattrs (x=0xf69b5ce4, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#6  0x0817ffcd in merge_memattrs (x=0xf69b5cf0, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#7  0x0817ffcd in merge_memattrs (x=0xf69b5cfc, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#8  0x0817ffcd in merge_memattrs (x=0xf69b5d08, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#9  0x0817ffcd in merge_memattrs (x=0xf69b5d14, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#10 0x0817ffcd in merge_memattrs (x=0xf6934460, y=Variable "y" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:981
#11 0x08180bd4 in try_crossjump_to_edge (mode=19, e1=Variable "e1" is not available.
) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:1148
#12 0x08181ec1 in try_crossjump_bb (mode=19, bb=0xf6a8cb54) at /home/gates/pinskia/src/gnu/
gcc/src/gcc/cfgcleanup.c:1803
#13 0x08182fcf in cleanup_cfg (mode=19) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cfgcleanup.c:
1990
#14 0x083e573f in rest_of_handle_flow2 () at /home/gates/pinskia/src/gnu/gcc/src/gcc/passes.c:
1370
#15 0x083e611e in rest_of_compilation () at /home/gates/pinskia/src/gnu/gcc/src/gcc/passes.c:1773


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |rtl-optimization
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-29 14:01 -------
Reduced to:
typedef union {
    int Node;
    double dbl;
    long lng;
    char log;
    char str[256];
} FFSTYPE;
extern FFSTYPE fflval;
int fflex ( void )
 {
 char *fname;

 fname = &fflval.str[0];
 if( ((fname)[0]<("BOX(")[0]? -1:(fname)[0]>("BOX(")[0]?1:strcmp((fname),("BOX(")))==0
      || ((fname)[0]<("CIRCLE(")[0]? -1:(fname)[0]>("CIRCLE(")[0]?1:strcmp((fname),("CIRCLE(")))==0
   )
  return( 264 );
}

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-09-29 14:01:58
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-29 14:03 -------
: Search converges between 2004-07-21-trunk (#492) and 2004-07-23-trunk (#493).

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-29 14:12 -------
Here is something little smaller:
typedef union {
    char str[256];
} FFSTYPE;
extern FFSTYPE fflval;
int fflex ( void )
{
 char *fname;
 fname = &fflval.str[0];
 if( (fname[0]>'B'?1:strcmp(fname,"BO"))==0
     || (fname[0]<'C'? -1:strcmp(fname,"CI"))==0
   )
  return 264;
return 0;
}

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-29 14:27 -------
Here is one without "?:" (taken from the tree dumps and modified a little to remove the gotos):
typedef union {
    char str[256];
} FFSTYPE;
extern FFSTYPE fflval;
int fflex ( void )
{
  int D1130;
  if (fflval.str[0] > 66)
  {
    if (strcmp (&fflval.str[0], &"CI"[0]) != 0)
      return 0;
  }
  else if (strcmp (&fflval.str[0], &"BO"[0]) != 0)
    return 0;
  return 264;
}

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-29 14:42 -------
"-fcrossjumping -O1" is only needed to reproduce this bug.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2

[bangerth at dealii dot org]

------- Additional Comments From bangerth at dealii dot org  2004-09-29 16:33 -------
Admittedly only marginally shorter: 
--------------------------- 
struct { char c; } s; 
 
int main () { 
  if (s.c) { 
    if (strcmp (&s.c, &"A"[0])) return 0; 
  } 
  else 
    if (strcmp (&s.c, &"B"[0])) return 0; 
  return 1; 
} 
----------------------------- 
g/x> /home/bangerth/bin/gcc-4.0-pre/bin/gcc -O2 -c x.c 
x.c: In function 'main': 
x.c:10: internal compiler error: Segmentation fault 
Please submit a full bug report, 
with preprocessed source if appropriate. 
See <URL:http://gcc.gnu.org/bugs.html> for instructions. 
 
W. 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0.0 regression] gcc segfaults with -O2

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-05 04:34 -------
I think this is related to expanding strcmp.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.0.0 regression] [ICE on  |[4.0.0 regression] gcc
                   |legal code] gcc segfaults   |segfaults with -O2
                   |with -O2                    |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0 regression] gcc segfaults with -O2

[aj at gcc dot gnu dot org]

------- Additional Comments From aj at gcc dot gnu dot org  2004-10-10 08:44 -------
I see this same segfault in several of mine testcases on x86-64. 

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0 regression] gcc segfaults with -O2

[rakdver at gcc dot gnu dot org]

------- Additional Comments From rakdver at gcc dot gnu dot org  2004-10-10 14:43 -------
Patch:

http://gcc.gnu.org/ml/gcc-patches/2004-10/msg00852.html

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0 regression] gcc segfaults with -O2

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-10-16 16:42 -------
Subject: Bug 17723

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	rakdver@gcc.gnu.org	2004-10-16 16:42:32

Modified files:
	gcc            : ChangeLog cfgcleanup.c 

Log message:
	PR rtl-optimization/17723
	* cfgcleanup.c (merge_memattrs): Handle case when
	MEM_SIZE == NULL_RTX.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.5904&r2=2.5905
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cfgcleanup.c.diff?cvsroot=gcc&r1=1.131&r2=1.132



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0 regression] gcc segfaults with -O2

[rakdver at gcc dot gnu dot org]

------- Additional Comments From rakdver at gcc dot gnu dot org  2004-10-16 16:43 -------
Fixed.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723

[Bug rtl-optimization/17723] [4.0 regression] gcc segfaults with -O2

[rakdver at gcc dot gnu dot org]

------- Additional Comments From rakdver at gcc dot gnu dot org  2004-10-16 16:43 -------
Really :-)

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723