[Bug preprocessor/94367] pragma GCC diagnostics messes up with one line "if" blocks without curly braces

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94367

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
pragma GCC diagnostics
is a full statement.