[Bug bootstrap/55566] New: [4.8 regression] [IA64] ICE during bootstrap (related to recent "vec" re-implementation?)

["gary at intrepid dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55566

             Bug #: 55566
           Summary: [4.8 regression] [IA64] ICE during bootstrap (related
                    to recent "vec" re-implementation?)
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: gary@intrepid.com


Created attachment 28854
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28854
build failure: IA64 segv - first seen in r193595

GCC fails to build, due to a segmentation violation while compiling libgcc2
during the bootstrap phase on an IA64 (altix) running SuSE SLES 11.1.  The
installed gcc compiler is "gcc (SUSE Linux) 4.3.4 [gcc-4_3-branch revision
152973]", which is the compiler used to initially build gcc.

Bisection indicates that this started to fail with this svn revision.

------------------------------------------------------------------------
r193595 | dnovillo | 2012-11-17 18:54:30 -0800 (Sat, 17 Nov 2012) | 537 lines

This patch rewrites the old VEC macro-based interface into a new one
based on the template class 'vec'.  The user-visible changes are
described in http://gcc.gnu.org/wiki/cxx-conversion/cxx-vec.
[...]

It has continued to fail subsequent to that commit at least through 2012-11-30.

Since about 2012-11-27, the segmentation violations that trace back originating
through vec.h persist, but now the failure occurs when compiling a configure
test when beginning to build libgcc.   This continues to fail for a recent
version of gcc trunk (r194044 2012-12-01).

An excerpt configure test failure traceback is as follows.

conftest.c: In function 'foo':
conftest.c:19:1: internal compiler error: Segmentation fault
 }
 ^
0x4000000000b3b33f crash_signal
        src/gcc/toplev.c:334
0x4000000000466f30 vec<df_ref_d*, va_stack, vl_embed>::space(unsigned int) cons
t
        src/gcc/vec.h:842
0x4000000000466f30 vec<df_ref_d*, va_stack, vl_embed>::quick_push(df_ref_d* con
st&)
        src/gcc/vec.h:947
0x4000000000466f30 vec<df_ref_d*, va_stack, vl_ptr>::quick_push(df_ref_d* const
&)
        src/gcc/vec.h:1552
0x4000000000466f30 vec<df_ref_d*, va_stack, vl_ptr>::safe_push(df_ref_d* const&
)
        src/gcc/vec.h:1565
0x4000000000466f30 df_ref_create_structure
0x4000000000466f30 df_ref_create_structure
        src/gcc/df-scan.c:2804
0x4000000000467b3f df_ref_record
        src/gcc/df-scan.c:2873
0x400000000046923f df_get_call_refs
        src/gcc/df-scan.c:3403
[...]

More complete logs with trace back are attached.