[Bug c++/55443] New: ICE for some placement new expressions inside noexcept operator

[Bug c++/55443] New: ICE for some placement new expressions inside noexcept operator

[vlukas at gmx dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55443

             Bug #: 55443
           Summary: ICE for some placement new expressions inside noexcept
                    operator
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: vlukas@gmx.de


Created attachment 28762
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28762
Preprocessed c++ source using placement new inside noexcept

The attached code causes an ICE with both GCC 4.7.2 and a GCC 4.8.0 prerelease.
Output of "c++ -v" for the latter is:
-----------------------------------------------------------
Using built-in specs.
COLLECT_GCC=/home/lima/vanilla_installs/gcc_and_tools/bin/c++
COLLECT_LTO_WRAPPER=/home/lima/vanilla_installs/gcc_and_tools/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc_svn/configure
--prefix=/home/lima/vanilla_installs/gcc_and_tools --enable-__cxa_atexit
--enable-languages=c,c++ --disable-nls --disable-multilib
Thread model: posix
gcc version 4.8.0 20121122 (experimental) (GCC)
-----------------------------------------------------------

The command line was: 
c++ -std=c++0x noexcept_operator_constexpr.ice.ii
That triggers the following output:
-------------------------------------------------------
noexcept_operator_constexpr.ice.cc: In function 'int main()':
noexcept_operator_constexpr.ice.cc:9:30:   in constexpr expansion of
'((X*)<anonymous>)->X::X()'
noexcept_operator_constexpr.ice.cc:9:31: internal compiler error: in
cxx_eval_call_expression, at cp/semantics.c:6687
 };
                               ^
0x6b742f cxx_eval_call_expression
        ../../gcc_svn/gcc/cp/semantics.c:6686
0x6b05bb cxx_eval_constant_expression
        ../../gcc_svn/gcc/cp/semantics.c:7672
0x6b1f28 is_sub_constant_expr(tree_node*)
        ../../gcc_svn/gcc/cp/semantics.c:8047
0x6732a7 check_noexcept_r
        ../../gcc_svn/gcc/cp/except.c:1162
0xcaa5bb walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, pointer_set_t*, tree_node* (*)(tree_node**, int*, tree_node*
(*)(tree_node**, int*, void*), void*, pointer_set_t*))
        ../../gcc_svn/gcc/tree.c:10655
0xcaaa9d walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, pointer_set_t*, tree_node* (*)(tree_node**, int*, tree_node*
(*)(tree_node**, int*, void*), void*, pointer_set_t*))
        ../../gcc_svn/gcc/tree.c:10909
0xcaaa9d walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, pointer_set_t*, tree_node* (*)(tree_node**, int*, tree_node*
(*)(tree_node**, int*, void*), void*, pointer_set_t*))
        ../../gcc_svn/gcc/tree.c:10909
0xcaa0e4 walk_tree_without_duplicates_1(tree_node**, tree_node*
(*)(tree_node**, int*, void*), void*, tree_node* (*)(tree_node**, int*,
tree_node* (*)(tree_node**, int*, void*), void*, pointer_set_t*))
        ../../gcc_svn/gcc/tree.c:10936
0x672e6d expr_noexcept_p(tree_node*, int)
        ../../gcc_svn/gcc/cp/except.c:1239
0x673004 finish_noexcept_expr(tree_node*, int)
        ../../gcc_svn/gcc/cp/except.c:1224
0x62d116 cp_parser_unary_expression
        ../../gcc_svn/gcc/cp/parser.c:6554
0x62db17 cp_parser_binary_expression
        ../../gcc_svn/gcc/cp/parser.c:7344
0x62dfb6 cp_parser_assignment_expression
        ../../gcc_svn/gcc/cp/parser.c:7569
0x62fee2 cp_parser_expression
        ../../gcc_svn/gcc/cp/parser.c:7720
0x6305fe cp_parser_expression_statement
        ../../gcc_svn/gcc/cp/parser.c:9000
0x626557 cp_parser_statement
        ../../gcc_svn/gcc/cp/parser.c:8852
0x6277de cp_parser_statement_seq_opt
        ../../gcc_svn/gcc/cp/parser.c:9118
0x627926 cp_parser_compound_statement
        ../../gcc_svn/gcc/cp/parser.c:9072
0x638e33 cp_parser_function_body
        ../../gcc_svn/gcc/cp/parser.c:17648
0x638e33 cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc_svn/gcc/cp/parser.c:17684
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
-----------------------------------------------------------

Some variations of the attached code crash the compiler too. One of them is:
------------------------------------------------------------
#include <stddef.h>

struct X {
  X() = default;

  X(int);

  void* operator new(size_t, void*) noexcept;
};

X x;

bool b = noexcept(new(0) X);
-----------------------------------------------------------------

With respect to the code snippet immediately above, the compiler does not
produce an ICE when any single item of the following is applied:
1. Removing the variable definition of "x".
2. Changing the variable definition to "X x{0};".
3. Removing the noexcept specifier from the operator new declaration.
4. Removing the constructor declaration "X(int);"
5. Changing the final line to "bool b = noexcept(new(0) X{});".

(Doing more than one of the above also seems to make the ICE go away, but I
have not tested every combination.)

[Bug c++/55443] ICE for some placement new expressions inside noexcept operator

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55443

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-11-22
                 CC|                            |jason at gcc dot gnu.org,
                   |                            |paolo.carlini at oracle dot
                   |                            |com
     Ever Confirmed|0                           |1

--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2012-11-22 19:06:42 UTC ---
I find this disturbing. How the evaluation of:

  noexcept(new(0) X);

can possibly be affected be a previous:

  X x;

???

Jason, any tip?

[Bug c++/55443] ICE for some placement new expressions inside noexcept operator

[paolo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55443

--- Comment #2 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> ---
Author: paolo
Date: Tue Nov 18 12:24:34 2014
New Revision: 217711

URL: https://gcc.gnu.org/viewcvs?rev=217711&root=gcc&view=rev
Log:
2014-11-18  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/55443
    * g++.dg/cpp0x/noexcept26.C: New.
    * g++.dg/cpp0x/noexcept27.C: Likewise.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/noexcept26.C
    trunk/gcc/testsuite/g++.dg/cpp0x/noexcept27.C
Modified:
    trunk/gcc/testsuite/ChangeLog

[Bug c++/55443] ICE for some placement new expressions inside noexcept operator

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55443

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|jason at gcc dot gnu.org,          |
                   |paolo.carlini at oracle dot com    |
         Resolution|---                         |FIXED
   Target Milestone|---                         |5.0

--- Comment #3 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Fixed.