On July 19, 2025 11:50:37 PM PDT, "H. Peter Anvin" <hpa@xxxxxxxxx> wrote: >"auto" was defined as a keyword back in the K&R days, but as a storage >type specifier. No one ever used it, since it was and is the default >storage type for local variables. > >C++11 recycled the keyword to allow a type to be declared based on the >type of an initializer. This was finally adopted into standard C in >C23. > >gcc and clang provide the "__auto_type" alias keyword as an extension >for pre-C23, however, there is no reason to pollute the bulk of the >source base with this temporary keyword; instead define "auto" as a >macro unless the compiler is running in C23+ mode. Yeah, this is good. We have typeof() used extensively in macros all over. I'll try this for fortify macros and see if we see any binary output changes... -- Kees Cook
