[Bug preprocessor/58770] GCC very slow compiling with #pragma once

[manu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58770

Manuel López-Ibáñez <manu at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-06-27
                 CC|                            |manu at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #2 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
The GCC preprocessor is very optimized for include guards. Perhaps the same
optimizations are not applied for "#pragma once". Someone will need to
investigate where the two code paths differ and what could be the reason for
the slow-down.

Unfortunately, there are very few developers working on the preprocessor and
very few users of "#pragma once", so this will likely have very low priority
unless one of those users takes the lead to fix it.