Comment 5 for bug 968766

FWIW, I've built a "vanilla" GCC 4.6.3 from scratch (along with GMP 5.0.4, MPFR 3.1.0-p8, MPC 0.9, PPL 0.12, CLooG 0.15.11 and libelf 0.8.13), installed it (as well as the libraries) under /usr/local, and don't get any crashes with that version. In particular, both MPFR and Singular build just fine with '-O3'.

The crash on Singular 3-1-3-3 (cc1plus) with '-O3' also happens with GCC 4.6.3-1ubuntu3 in a 32-bit virtual machine (Precise with all recent updates), as a friend just confirmed. (To trigger this, one has to [also] put '-O3' into CPPFLAGS, not just CXXFLAGS, since otherwise the setting gets overridden by a subsequent '-O2' in the compile command.)