On Wed, 20 May 2020 at 22:35, Ted Toth via Gcc <gcc@xxxxxxxxxxx> wrote: > > I work on a project with a large code base some of which is pretty old. We > are discussing adding -std=gnu++11 to our g++ compiles to be able to use > newer classes/features but there are concerns that there could be > unintended consequences. For existing code that doesn't use any new > features/classes can it be expected that its function will not be altered > by use of this flag? Will we have to regression all of our c++ code? This question is not suitable for this mailing list, which is for discussing development of GCC itself. Please use gcc-help instead, as explained at https://gcc.gnu.org/lists.html (I've changed the mailing list in the CC header already). Subclause [diff.cpp03.lex] in the C++ standard lists differences between C++11 and C++03. In most cases the changes will cause new diagnostics for code that is valid in C++03, but will not change the meaning. The change that is most likely to compile without diagnostics but behave differently at runtime is that destructors are implicitly noexcept in C++11, so a destructor that throws an exception will call std::terminate() unless you modify the code to add noexcept(false) to the destructor.
