[Bug c++/39056] New: [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[Bug c++/39056] New: [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[reichelt at gcc dot gnu dot org]

The following invalid code snippet triggers an ICE on the trunk:

==============================
__complex__ int i({0});
==============================

bug.cc:1: internal compiler error: in process_init_constructor, at
cp/typeck2.c:1192
Please submit a full bug report, [etc.]

The bug appeared with the introduction of initializer lists:

2008-07-02  Jason Merrill  <jason@redhat.com>

        * Make-lang.in (cp/typeck2.o): Add $(REAL_H) dependency.

        Implement WG21 N2672, Initializer List proposed wording
        * cp-tree.h (enum cp_tree_index): Add CPTI_INIT_LIST_TYPE.
        (struct lang_type_class): Add has_list_ctor bitfield.
        (TYPE_HAS_LIST_CTOR): New macro.
        (BRACE_ENCLOSED_INITIALIZER_P): Expect init_list_type_node.
        ...

It's a regression since the same code snippet didn't cause a crash before.


-- 
           Summary: [4.4 regression] [c++0x] ICE with invalid initializer
                    list for complex variable
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code, monitored
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reichelt at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[reichelt at gcc dot gnu dot org]

-- 

reichelt at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[jakub at gcc dot gnu dot org]

------- Comment #1 from jakub at gcc dot gnu dot org  2009-02-02 11:18 -------
I think this depends on whether we want as an exception allow this or not.

If not, e.g.:
--- typeck2.c.jj22009-01-13 18:32:14.000000000 +0100
+++ typeck2.c2009-02-02 12:15:58.000000000 +0100
@@ -789,7 +789,8 @@ digest_init_r (tree type, tree init, boo
     }

   /* Handle scalar types (including conversions) and references.  */
-  if (TREE_CODE (type) != COMPLEX_TYPE
+  if ((TREE_CODE (type) != COMPLEX_TYPE
+       || BRACE_ENCLOSED_INITIALIZER_P (init))
       && (SCALAR_TYPE_P (type) || code == REFERENCE_TYPE))
     {
       tree *exp;

gets rid of the ICE, instead it will reject it with:
pr39056.C:1: error: cannot convert '<brace-enclosed initializer list>' to 'int
__complex__' in initialization


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[jason at gcc dot gnu dot org]

------- Comment #2 from jason at gcc dot gnu dot org  2009-02-02 19:02 -------
Jakub's patch looks fine to me.

Benjamin, does you have an opinion about initializer-lists and complex?  I
guess the library complex class will accept { real, imag } naturally because it
has a suitable constructor.

Note that initialization with = { 0 } still works normally, and = { 0, 0 } is
still rejected as having too many initializers for a scalar, like in C.


-- 

jason at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2009-02-03 17:23 -------
Subject: Bug 39056

Author: jakub
Date: Tue Feb  3 17:23:11 2009
New Revision: 143899

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=143899
Log:
        PR c++/39056
        * typeck2.c (digest_init_r): Don't call process_init_constructor
        for COMPLEX_TYPE.

        * g++.dg/cpp0x/initlist13.C: New test.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/initlist13.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/typeck2.c
    trunk/gcc/testsuite/ChangeLog


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[jakub at gcc dot gnu dot org]

------- Comment #4 from jakub at gcc dot gnu dot org  2009-02-03 19:31 -------
Fixed.


-- 

jakub at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[bkoz at gcc dot gnu dot org]

------- Comment #6 from bkoz at gcc dot gnu dot org  2009-02-03 23:47 -------
Created an attachment (id=17240)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17240&action=view)
test std::complex, __complex init


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056

[Bug c++/39056] [4.4 regression] [c++0x] ICE with invalid initializer list for complex variable

[bkoz at gcc dot gnu dot org]

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------- Comment #5 from bkoz at gcc dot gnu dot org  2009-02-03 23:47 -------
> Benjamin, does you have an opinion about initializer-lists and complex?  I
> guess the library complex class will accept { real, imag } naturally because it
> has a suitable constructor.

It would be great if this stuff matched for C/C++. 

#include <complex>

std::complex<double> z1{1.1, 2.2};
std::complex<double> z2{3.3};
std::complex<double> z3{ };

all work with -std=gnu++0x, but not with -std=c++98. So, direct list init works
for C++ std::complex.

All forms of copy-list init fail for std::complex though.

std::complex<double> z4 = {1.1, 2.2};
std::complex<double> z5 = {3.3};
std::complex<double> z6 = { };

complex_init.cc:9: error: call of overloaded ‘complex(<brace-enclosed
initializer list>)’ is ambiguous
/mnt/share/bld/gcc/x86_64-unknown-linux-gnu/libstdc++-v3/include/complex:1174:
note: candidates are: std::complex<double>::complex(const std::complex<float>&)
/mnt/share/bld/gcc/x86_64-unknown-linux-gnu/libstdc++-v3/include/complex:1162:
note:                 std::complex<double>::complex(const
std::complex<double>&)

There seems to be some inconsistency in the way this is defined, will bring up
on libstdc++-ml/LWG. 

The original testcase:
__complex__ int i({0});

fails in the C++ version:

std::complex<double> i({0});

So that part is consistent.

-benjamin


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39056