[Bug c++/37716] New: ice for legal C++ code with -O2 on 20080926

["dcb314 at hotmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

I just tried to compile the Suse Linux package libQtWebKit-devel-4.4.0-11
with the new gcc version 4.4, snapshot dated 20080926.

gcc said

puzzlewidget.cpp: In member function 'virtual void
PuzzleWidget::mousePressEvent(Q
MouseEvent*)':
puzzlewidget.cpp:143: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Preprocessed source code attached. Flag -O2 required.

Here is a stack backtrace from valgrind

==23398== Invalid read of size 2
==23398==    at 0x8F4355: vn_nary_op_lookup (tree-ssa-sccvn.c:1149)
==23398==    by 0x8E2ECE: get_or_alloc_expr_for (tree-ssa-pre.c:1056)
==23398==    by 0x8E336C: fully_constant_expression (tree-ssa-pre.c:1138)
==23398==    by 0x8E7624: insert_aux (tree-ssa-pre.c:3398)
==23398==    by 0x8E7457: insert_aux (tree-ssa-pre.c:3471)
==23398==    by 0x8E7457: insert_aux (tree-ssa-pre.c:3471)
==23398==    by 0x8E7457: insert_aux (tree-ssa-pre.c:3471)
==23398==    by 0x8E8CF5: execute_pre (tree-ssa-pre.c:3492)
==23398==    by 0x8E8DEA: do_pre (tree-ssa-pre.c:4295)
==23398==    by 0x75C487: execute_one_pass (passes.c:1279)
==23398==    by 0x75C6C4: execute_pass_list (passes.c:1327)
==23398==    by 0x75C6DC: execute_pass_list (passes.c:1328)
==23398==  Address 0x0 is not stack'd, malloc'd or (recently) free'd


-- 
           Summary: ice for legal C++ code with -O2 on 20080926
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dcb314 at hotmail dot com
  GCC host triplet: suse-linux-x86_64


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37716