[Bug c++/46304] New: g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[Bug c++/46304] New: g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[apataki at apataki dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

           Summary: g++ crashes with ICE in bitmap_first_set_bit, at
                    bitmap.c:770
           Product: gcc
           Version: 4.5.1
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: apataki@apataki.net


g++ 4.5.1 crashes with an internal compiler error on the following C++ code
(trimmed down from a larger codebase - in this shortened state it is clearly
not expected to work/do anything useful):


#include <complex.h>


template<class T>
class ClassA
{
    complex double *data;

public:
    void setSize()
    {
    data[0] = 1.0 + 2.0i;
    }
};


template<class TCoeff, class TRHS>
class ClassB
{
    ClassA<TCoeff> a1;
    ClassA<TRHS> a2;

public:
    void setSize()
    {
    a1.setSize();
    a2.setSize();
    }
};


class ClassC
{
    ClassB<double, complex double> d;
    virtual void init();
};

void ClassC::init()
{
    d.setSize();
}



$ g++ -c z8.cc
z8.cc: In member function ‘void ClassA<T>::setSize() [with T = __complex__
double]’:
z8.cc:41:1: internal compiler error: in bitmap_first_set_bit, at bitmap.c:770
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://bugzilla.redhat.com/bugzilla> for instructions.
Preprocessed source stored into /tmp/ccL3ZMfZ.out file, please attach this to
your bugreport.


$ g++ -v
Using built-in specs.
COLLECT_GCC=/usr/bin/g++
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/4.5.1/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla
--enable-bootstrap --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-gnu-unique-object
--enable-linker-build-id
--enable-languages=c,c++,objc,obj-c++,java,fortran,ada,lto --enable-plugin
--enable-java-awt=gtk --disable-dssi
--with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre
--enable-libgcj-multifile --enable-java-maintainer-mode
--with-ecj-jar=/usr/share/java/eclipse-ecj.jar --disable-libjava-multilib
--with-ppl --with-cloog --with-tune=generic --with-arch_32=i686
--build=x86_64-redhat-linux
Thread model: posix
gcc version 4.5.1 20100924 (Red Hat 4.5.1-4) (GCC) 

This is on a Fedora 14 x86-64 system.

[Bug c++/46304] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[apataki at apataki dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #1 from Andras Pataki <apataki at apataki dot net> 2010-11-04 21:01:49 UTC ---
I have also tried this code on the latest gcc 4.6 snapshot (4.6-20101030) and
it also produces a crash, although with a slightly different error message:

$ /opt/gcc/4.6-20101030/bin/g++ -v
Using built-in specs.
COLLECT_GCC=/opt/gcc/4.6-20101030/bin/g++
COLLECT_LTO_WRAPPER=/mnt/other/opt/gcc/4.6-20101030/bin/../libexec/gcc/x86_64-redhat-linux/4.6.0/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../gcc-4.6-20101030/configure --prefix=/opt/gcc/4.6-20101030
--enable-bootstrap --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-gnu-unique-object
--enable-linker-build-id --enable-languages=c,c++,fortran --enable-plugin
--disable-dssi --with-ppl --with-cloog --with-tune=generic --with-arch_32=i686
--build=x86_64-redhat-linux
Thread model: posix
gcc version 4.6.0 20101030 (experimental) (GCC) 


$ /opt/gcc/4.6-20101030/bin/g++ -c z8.cc 
z8.cc: In member function ‘void ClassA<T>::setSize() [with T = double]’:
z8.cc:26:2:   instantiated from ‘void ClassB<TCoeff, TRHS>::setSize() [with
TCoeff = double, TRHS = __complex__ double]’
z8.cc:40:15:   instantiated from here
z8.cc:12:2: internal compiler error: in tsubst_copy, at cp/pt.c:11376
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

[Bug c++/46304] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2010.11.04 23:05:10
                 CC|                            |jason at redhat dot com
     Ever Confirmed|0                           |1

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> 2010-11-04 23:05:10 UTC ---
It is caused by revision 156874:

http://gcc.gnu.org/ml/gcc-cvs/2010-02/msg00457.html

[Bug c++/46304] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2010-11-05 05:57:03 UTC ---
Author: jason
Date: Fri Nov  5 05:56:58 2010
New Revision: 166350

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=166350
Log:
    PR c++/46304
    * pt.c (tsubst_copy): Handle COMPLEX_CST.

Added:
    trunk/gcc/testsuite/g++.dg/ext/complex6.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/pt.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|NEW                         |ASSIGNED
      Known to work|                            |4.4.4, 4.6.0
         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org
                   |gnu.org                     |
   Target Milestone|---                         |4.5.2
            Summary|g++ crashes with ICE in     |[4.5 Regression] g++
                   |bitmap_first_set_bit, at    |crashes with ICE in
                   |bitmap.c:770                |bitmap_first_set_bit, at
                   |                            |bitmap.c:770
      Known to fail|                            |4.5.0, 4.5.1

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-05 10:48:55 UTC ---
Confirmed.  Happens as we go into SSA form.

#2  0x00000000007ed310 in bitmap_first_set_bit (a=0x19c13e8)
    at /space/rguenther/src/svn/gcc-4_5-branch/gcc/bitmap.c:770
770       gcc_assert (elt);
(gdb) 
#3  0x0000000000c61587 in set_livein_block (var=0x7ffff7ef3d20, 
    bb=0x7ffff5b318f0)
    at /space/rguenther/src/svn/gcc-4_5-branch/gcc/tree-into-ssa.c:550
550           int def_block_index = bitmap_first_set_bit (db_p->def_blocks);

when visiting

(gdb) call debug_gimple_stmt (stmt)
D.2447 = COMPLEX_EXPR <D.2444, 2.0e+0>;

and the bitmap is empty.  D.2444 is not set before.

void ClassA<T>::setSize() [with T = __complex__ double] (struct ClassA * const
this)
{
  complex double D.2447;
  complex double * D.2446;

<bb 2>:
  D.2446 = this->data;
  D.2447 = COMPLEX_EXPR <D.2444, 2.0e+0>;
  *D.2446 = D.2447;
  return;

}

it looks like this caller to bitmap_first_set_bit assumes it's ok to
call it on an empty bitmap where it should return -1.

It's interesting though that 4.6 for the above has

void ClassA<T>::setSize() [with T = __complex__ double] (struct ClassA * this)
{
  complex double D.2421;
  double D.2420;
  complex double * D.2419;

<bb 2>:
  D.2419 = this->data;
  D.2420 = 1.0e+0 + 0.0;
  D.2421 = COMPLEX_EXPR <D.2420, 2.0e+0>;
  *D.2419 = D.2421;
  return;

}

which shows it's also really a wrong-code bug.

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #5 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-05 10:54:59 UTC ---
Smaller testcase - I suspect a tree sharing issue.

template<int i>
struct ClassA
{
  _Complex double *data;
  void setSize() { data[0] = 1.0 + 2.0i; }
};

void foo(void)
{
  ClassA<0> a1;
  ClassA<1> a2;
  a1.setSize();
  a2.setSize();
}

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

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

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

--- Comment #6 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-05 11:20:00 UTC ---
Hm.  In 4.6 two different COMPLEX_EXPRs are built by tsubst, via
cp_build_binary_op (PLUS_EXPR, ...).  In 4.5 we end up with a COMPLEX_EXPR
at tsubst time which we don't handle explicitly but pass through from
tsubst_copy default case (which would ICE on trunk).

Jason?

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
                 CC|                            |rguenth at gcc dot gnu.org

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #7 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-14 11:40:22 UTC ---
Even though it looks similar to PR45959 backporting the C++ revisions 165306
and 165307 does not fix the tree sharing problem on the 4.5 branch.

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[apataki at apataki dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #8 from Andras Pataki <apataki at apataki dot net> 2010-11-16 15:11:04 UTC ---
I can confirm that my test case now compiles and runs correctly with the
20101113 snapshot of the 4.6 compiler.

However, I've noticed another strangeness relating to complex numbers.  Both
the 4.5.x and the 4.6 snapshot do not treat complex constants quite the way I'd
expect:

#include <complex.h>

class A
{
    static const complex double x = 1.0 + 2.0i;
};


4.5.1 says:
z9.cc:5:41: error: ‘A::x’ cannot be initialized by a non-constant expression
when being declared

4.6-20101113 says:
z9.cc:5:40: error: field initializer is not constant

but 4.4.5 compiles it without complaints.
This is the same even if I use the notation 1.0 + 2.0*I for the constant.

Andras

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.5.2                       |4.5.3

--- Comment #9 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-12-16 13:02:56 UTC ---
GCC 4.5.2 is being released, adjusting target milestone.

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #10 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-04-18 14:28:50 UTC ---
C++ people?

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                 CC|                            |jason at gcc dot gnu.org
         AssignedTo|unassigned at gcc dot       |jason at gcc dot gnu.org
                   |gnu.org                     |

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #12 from Jason Merrill <jason at gcc dot gnu.org> 2011-04-20 06:31:09 UTC ---
Author: jason
Date: Wed Apr 20 06:31:07 2011
New Revision: 172755

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=172755
Log:
    PR c++/46304
    * typeck.c (cp_build_binary_op): Fold COMPLEX_EXPR.

Added:
    branches/gcc-4_5-branch/gcc/testsuite/g++.dg/ext/complex7.C
Modified:
    branches/gcc-4_5-branch/gcc/cp/ChangeLog
    branches/gcc-4_5-branch/gcc/cp/typeck.c
    branches/gcc-4_5-branch/gcc/testsuite/ChangeLog

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #13 from Jason Merrill <jason at gcc dot gnu.org> 2011-04-20 06:31:54 UTC ---
Author: jason
Date: Wed Apr 20 06:31:51 2011
New Revision: 172756

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=172756
Log:
    PR c++/46304
    * typeck.c (cp_build_binary_op): Fold COMPLEX_EXPR.

Added:
    branches/gcc-4_6-branch/gcc/testsuite/g++.dg/ext/complex7.C
Modified:
    branches/gcc-4_6-branch/gcc/cp/ChangeLog
    branches/gcc-4_6-branch/gcc/cp/typeck.c
    branches/gcc-4_6-branch/gcc/testsuite/ChangeLog

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

--- Comment #11 from Jason Merrill <jason at gcc dot gnu.org> 2011-04-20 06:30:45 UTC ---
Author: jason
Date: Wed Apr 20 06:30:41 2011
New Revision: 172754

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=172754
Log:
    PR c++/46304
    * typeck.c (cp_build_binary_op): Fold COMPLEX_EXPR.

Added:
    trunk/gcc/testsuite/g++.dg/ext/complex7.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/typeck.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/46304] [4.5 Regression] g++ crashes with ICE in bitmap_first_set_bit, at bitmap.c:770

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46304

Jason Merrill <jason at gcc dot gnu.org> changed:

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

--- Comment #14 from Jason Merrill <jason at gcc dot gnu.org> 2011-04-20 06:48:56 UTC ---
Fixed.