https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68524
Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2018-09-14 CC| |msebor at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> --- Clang also supports the syntax with a warning. Confirmed (I have no idea how challenging it might be to implement). There also is a proposal to add the standard C++ attribute syntax (e.g., [[gnu::const]]) to C. The C++ syntax doesn't allow attributes there.