https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58770
--- Comment #4 from Manuel López-Ibáñez <manu at gcc dot gnu.org> --- (In reply to Tom Tromey from comment #3) > I think the rationale for this code is that the #pragma must > prevent a second inclusion, even if done by a different file > name; whereas #ifdef exclusion doesn't suffer from this issue. Sorry, I don't understand this. The #ifdef include-guards do prevent a second inclusion, even if done by a different file name, no?