[Bug pch/53880] [4.8 Regression] compile time regression when generating precompiled headers for boost

[markus at trippelsdorf dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53880

--- Comment #31 from Markus Trippelsdorf <markus at trippelsdorf dot de> 2012-07-30 16:26:23 UTC ---
(In reply to comment #30)
> Created attachment 27898 [details]
> Hack to avoid quadratic loops
> 
> This makes use of the assumption that this_obj and its comparison companion are
> loop invariant (they have to be for pointer rewriting). Drops compile time to
> worse-than-gcc47-but-acceptable levels.
> 
> Markus, could you give this a try, please?

Looks very good:

 % time c++ -c -o pch.hpp.gch /usr/include/boost/math/special_functions.hpp
c++ -c -o pch.hpp.gch /usr/include/boost/math/special_functions.hpp  2.67s user
0.20s system 99% cpu 2.888 total

Thanks a lot, Steven.