id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
4523,fix for #4501,ookami1@…,No-Maintainer,"The following three patches fix issue #4501.
detail_auto_rec.patch and repetition_for.patch extend the maximum loop count in BOOST_PP_FOR from 255 to 256.
seq_for_each.patch modifies the state of BOOST_PP_SEQ_FOR_EACH in such a way that the calculation of the sequence size is done just once now, and its cached value is used for loop control instead. This cuts down on the evaluation cost especially for long sequences.
Small sequences benefit from an early-out execution path, in the frequent case, when no outer for loop blocks iteration slots.

I manually enabled configuration flags 0x0004, 0x0010, 0x0020 (MSVC, BCC, EDG resp.) to enforce the execution of compiler specific code under GCC, and they compiled and executed fine, but that is only a poor replacement for the native compilers, of course. The code for MWCC and DMG does not conform to C90 or later, so GNU gcc could not be fooled to emulate them.

cheers

Wolf Lammen

 
complexity:


BOOST_CONFIG_FLAGS 0x0001 (strict)



{{{
boost 1.43.0:                     patched:

  0 elements   345 replacements      67 replacements
  1            388                  105
  2            431                  142
  4            520                  216
  8            710                  364
 16           1138                  660
 32           2186                 1252
 64           5050                 2436
128          13850                 4804
255 elements 43441 replacements    9503
256          failure               9540


}}}
",Patches,closed,Boost 1.44.0,preprocessor,Boost 1.44.0,Problem,fixed,,