While compiling a simple class containing a std::tr1::unordered_map member as a library, linking to the library and creating an object generate illegal hardware instruction. Or at least, running the code raise a SIGILL. The library file is lib.cc and the main program is test_lib.cc. The commands used to compile the two are:
g++ -W -Wall --fast-math -msse4 -shared -o libl.so lib.cc -fPIC g++ -W -Wall --fast-math -msse4 -o test_lib test_lib.cc -L. -ll The bug appears only if both --fast-math and -msse4 are used. The bug already existed in g++ 4.4.1 (the one with provided by Fedora 11). Here are the informations about the version of gcc I use: Using built-in specs. Target: x86_64-unknown-linux-gnu Configured with: ./configure --prefix=/usr/local/stow/gcc-4.4.2 Thread model: posix gcc version 4.4.2 (GCC) -- Summary: Illegal instruction generated while compiling with optimization Product: gcc Version: 4.4.2 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: pbdr at uea dot ac dot uk GCC build triplet: x86_64-redhat-linux GCC host triplet: x86_64-redhat-linux GCC target triplet: x86_64-redhat-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42332