https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64051
--- Comment #3 from Pierre Ossman <ossman at cendio dot se> --- libstdc++ compiles fine though, but the previous stage did indeed include a C++ compiler. But even with that requirement, it still seems a bit dangerous. What if the previous compiler uses a different exception model? Or changes some other of all the myriad of options that affect compiler behaviour? First compiler (from RHEL 7): $ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/4.8.2/lto-wrapper Target: x86_64-redhat-linux Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --with-linker-hash-style=gnu --enable-languages=c,c++,objc,obj-c++,java,fortran,ada,go,lto --enable-plugin --enable-initfini-array --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.8.2-20140120/obj-x86_64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.2-20140120/obj-x86_64-redhat-linux/cloog-install --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux Thread model: posix gcc version 4.8.2 20140120 (Red Hat 4.8.2-16) (GCC) Second compiler: $ i686-pc-linux-gnu-gcc -v Using built-in specs. COLLECT_GCC=/opt/cendio-build/arch/armhf/usr/bootstrap/bin/i686-pc-linux-gnu-gcc COLLECT_LTO_WRAPPER=/opt/cendio-build/arch/armhf/usr/bootstrap/libexec/gcc/i686-pc-linux-gnu/4.5.4/lto-wrapper Target: i686-pc-linux-gnu Configured with: ../configure --prefix=/opt/cendio-build/arch/armhf/usr/bootstrap --with-gmp=/opt/cendio-build/arch/armhf/usr/bootstrap --with-mpfr=/opt/cendio-build/arch/armhf/usr/bootstrap --with-mpc=/opt/cendio-build/arch/armhf/usr/bootstrap --target=i686-pc-linux-gnu --with-sysroot=/opt/cendio-build/arch/armhf --with-system-zlib --with-gnu-as --with-gnu-ld --disable-nls --disable-multilib --disable-libmudflap --enable-shared --enable-threads=posix --enable-languages=c,c++ Thread model: posix gcc version 4.5.4 (GCC) Third compiler: ../configure --host=i686-pc-linux-gnu --prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/var/lib --mandir=/usr/share/man --infodir=/usr/share/info --build=cross-unknown-linux-gnu --with-build-sysroot=/opt/cendio-build/arch/osx32 --target=i686-pc-linux-gnu --with-sysroot=/ --with-system-zlib --with-gnu-as --with-gnu-ld --disable-nls --disable-multilib --disable-libmudflap --enable-shared --enable-threads=posix --enable-languages=c,c++,objc