First of all I would like to thank everybody who responded on my previous post. The real showstopper for me at the moment is date_time library. I did a small test -- compiled and run days_till_new_year.cpp against boost 1.29 (patched to not complain about __ICL 700) and current snapshot of boost CVS. Here is what I've got (cpp was renamed to test.cpp for short): ------------------------------------- C:\work\icl>icl Intel(R) C++ Compiler for 32-bit applications, Version 7.0 Build 20021018Z Copyright (C) 1985-2002 Intel Corporation. All rights reserved. 30 DAY EVALUATION LICENSE icl: Command line error: no files specified; for help type "icl -help" C:\work\icl>icl /MD /O2 /DDATE_TIME_INLINE /I..\boost_1_29_0 /nologo test.cpp test.cpp C:\work\icl>test Days till new year: -731982 C:\work\icl>icl /MD /Od /DDATE_TIME_INLINE /I..\boost_1_29_0 /nologo test.cpp test.cpp C:\work\icl>test Days till new year: 329 C:\work\icl>icl /MD /O2 /DDATE_TIME_INLINE /I..\boost /nologo test.cpp test.cpp C:\work\icl>test Days till new year: 3031841 C:\work\icl>icl /MD /Od /DDATE_TIME_INLINE /I..\boost /nologo test.cpp test.cpp C:\work\icl>test Days till new year: 329 ---------------------------------------------- As you can see both versions are broken. What I don't understand is how come that boost regression tests are Ok? Am I using wrong version of Intel Compiler, or am I missing some magic flags to compiler? I will send this report to Intel tech support; however I would appreciate if someone will verify these results, and contact Intel on behalf of Boost community. Regards, Kirill Lapshin.