On Thu, 2022-03-03 at 22:07 -0500, Abdullah Siddiqui via Gcc-help wrote: > Hello Jonathan. > > Thank you for the detailed clarification. > > > At what point did the GCC developers give up C++98 and start using C++11? > > > For GCC 11. This is stated at https://gcc.gnu.org/install/prerequisites.html > > > Are you referring to these lines: > > ISO C++11 compiler > > Necessary to bootstrap GCC. > > Versions of GCC prior to 11 also allow bootstrapping with an ISO C++98 > > compiler,..... > > > I thought bootstrapping and compilation are two separate things. In this > context, are bootstrapping and compilation the same i.e. GCC is a compiler > and the ISO C++11 compiler is being used to compile GCC? In theory, compiling GCC with --disable-bootstrap may have a *more* strict restriction on host compiler than bootstrapping (--enable- bootstrap is the default building a native compiler). It's because with --disable-bootstrap the entire GCC will be built with the host compiler, but with --enable-bootstrap only stage 1 is built with the host compiler, and stage 2 is built with stage 1. In stage 1 some optional features (Go or D compilers, etc) are not enabled. But in practice I don't know. Maybe it's possible to build GCC 11 with GCC 4.8 and --disable-bootstrap but I've not tried. I don't think it's really rational to spend an hour testing this in 2022. > The exceptions are some tests which have .c extensions but get > > compiled as both C and C++, when we want to test that both language > > front-ends pass the test. > > > Are you referring to files in the testsuite folders > (example: gcc/testsuite/g++.dg/lto/pr65302_1.C)? Files in g++.dg are purely C++. Please note ".C" (with a capital letter) is not same as ".c". For example, gcc/testsuite/c-c++-common/pr100785.c is compiled as both C and C++ during the testing process of GCC. > -- Xi Ruoyao <xry111@xxxxxxxxxxxxxxxx> School of Aerospace Science and Technology, Xidian University
