https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81068
--- Comment #2 from Piotr Stachura <piotr.stachura at delphi dot com> --- I have to check it deeper. I have 2 systems - one gentoo and one Ubuntu. On Ubuntu, code is correct (as I posted in bug report). When I compile this same code on gentoo (gcc-5.4.0 and gcc-7.2.0) I have this same results as you "terminate called after throwing an instance of 'std::range_error'". Maybe a locale settings are making a difference... LANG=pl_PL.utf8 vs LANG=pl_PL.UTF-8 On ubuntu: valgrind ./1 ==2581== Memcheck, a memory error detector ==2581== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al. ==2581== Using Valgrind-3.12.0.SVN and LibVEX; rerun with -h for copyright info ==2581== Command: ./1 ==2581== ==2581== ==2581== HEAP SUMMARY: ==2581== in use at exit: 0 bytes in 0 blocks ==2581== total heap usage: 3 allocs, 3 frees, 72,794 bytes allocated ==2581== ==2581== All heap blocks were freed -- no leaks are possible ==2581== ==2581== For counts of detected and suppressed errors, rerun with: -v ==2581== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0) gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/6/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu 6.2.0-7ubuntu11' --with-bugurl=file:///usr/share/doc/gcc-6/README.Bugs --enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-6 --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-6-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-6-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-6-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 6.2.0 20161018 (Ubuntu 6.2.0-7ubuntu11)