[Bug bootstrap/50686] [4.7 regression] IRIX 6.5 bootstrap failure: ICE in in lookup_cfa_1, at dwarf2cfi.c:595

[ro at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50686

--- Comment #35 from Rainer Orth <ro at gcc dot gnu.org> 2013-04-03 12:19:13 UTC ---
Created attachment 29792
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29792
new testcase

After some digging, I found a bit of what's going on: for a long time (before
4.7 branched) I'd been building on IRIX 6.5 with --enable-checking=release
since
that cuts down bootstrap time by ca. 30% to ca. 36 hours.  At some time after
the
release, I dropped that, assuming that it were the default on a release branch,
which is not true unfortunately.

I've now been able to massively the libstdc++ vec.cc failure and reproduce it
in a i386-pc-solaris2.11 x mips-sgi-irix6.5 cross compiler configured with

--disable-nls --target mips-sgi-irix6.5 \
        --with-gmp-include=/vol/gcc/include --with-gmp-lib=/vol/gcc/lib \
        --disable-libgomp --disable-libquadmath --disable-libssp --disable-lto
\
        --enable-obsolete --enable-languages=c,c++ --enable-checking

The --enable-checking is the key here.

With such a cc1plus, I get the following ICE:

% ./cc1plus -fpreprocessed vec.ii -quiet -mabi=n32 -g -O2 -o vec.s
vec.ii: In function 'void __cxxabiv1::__cxa_vec_delete2(void*, std::size_t,
std::size_t, __cxxabiv1::__cxa_cdtor_type, void (*)(void*))':
vec.ii:55:3: internal compiler error: in maybe_record_trace_start, at
dwarf2cfi.c:2231

  Rainer