Danke!
Woher weiß ich, ob ich einen neueren gcc-Compiler habe?
ii gcc 4:5.3.1-1ubuntu1 amd64 GNU C compiler
ii gcc-5 5.4.0-6ubuntu1~16.04.12 amd64 GNU C compiler
ii hardening-includes 2.7ubuntu2 all Makefile for enabling compiler flags for security hardening
ii libllvm3.8:amd64 1:3.8-2ubuntu4 amd64 Modular compiler and toolchain technologies, runtime library
ii libllvm6.0:amd64 1:6.0-1ubuntu2~16.04.1 amd64 Modular compiler and toolchain technologies, runtime library
ii libllvm6.0:i386 1:6.0-1ubuntu2~16.04.1 i386 Modular compiler and toolchain technologies, runtime library
ii libxkbcommon0:amd64 0.5.0-1ubuntu2.1 amd64 library interface to the XKB compiler - shared library
Habe ich auch 5.4.0 ?