[Bug c/52127] pedantic-errors is inconsistent in its behavior

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52127

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-02-05 21:39:16 UTC ---
You need -Wsystem-headers to enable the diagnostic in a system header

Stripping the # lines means it is no longer considered a system header