Re:GCC 16 considering changing default to C++20
by cogman10 on Monday November 17, 2025 @10:18AM
(#45954336)
> It's the type of dog fooding they should be doing! It's one reason why people care so much about self-hosted compilers, it's a demonstration of maturity of the language/compiler.
I could be misreading this, but unless they have a different understanding of what it means to dog fooding than I do then it seems like the proposal is to use C++20 features in the compiler bootstraping.
Re:GCC 16 considering changing default to C++20
by ziotom78 on Monday November 17, 2025 @10:28AM
(#45954406)
I believe they are really referring to the default mode used by GCC when no standard is explicitly stated.
The email mentions that the last time they changed it was 5 years ago in GCC 11, and the link <https://gcc.gnu.org/projects/cxx-status.html#cxx17> indeed says
> C++17 mode is the default since GCC 11; it can be explicitly selected with the -std=c++17 command-line flag, or -std=gnu++17 to enable GNU extensions as well.
which does not imply a change in an obscure feature (bootstrapping) that would only affect a few users.
It doesn't appear to me that the parent comment was implying otherwise.
The default is changing for any compilation that doesn't explicitly specify a standard version. I would have thought that the build process for a compiler is likely careful enough that it does explicitly specify a version.