To build the release version I use:
   bjam -j2 variant=release

On AIX this uses -03, unfortunately this causes some problems, so I want to replace
-03 in release mode with -02.

So in my site-config.jam file I tried:

project site-config
     : requirements <variant>release:<cxxflags>-02    # serialization has problems with -03
     ;

But when I ran this I got:

xlC_r -c -02 -DNDEBUG -qcpluscmt -O3 -qstrict -qfuncsect -qeh -qrtti -I"/s1a/emos_esuite/emos_data/sms/boost_1_42_0" -I"ACore/src" -o "ANattr/bin/vacpp/release/link-static/threading-multi/src/TodayAttr.o" "ANattr/src/TodayAttr.cpp"

/usr/local/lpp/vacpp11101/usr/vacpp/bin/.orig/xlC_r: 1501-216 (W) command option -02 is not recognized - passed to ld

It appears that <cxxflags> is only additive, is there any
way to actually replace flags compiler flags for a given build variant ?

Any help appreciated

Best regards,
Ta,
Avi