I can reproduce this bug as well on my feisty laptop (with all updates).

Compiling with -O1 works:

[EMAIL PROTECTED]:/tmp$ time g++ -O1 -c -o quickbook.o quickbook.cpp

real    0m29.831s
user    0m28.926s
sys     0m0.476s


Compiling with -O2 does not seem to end (I waited 15 minutes which I assume is 
more than enough)

[EMAIL PROTECTED]:/tmp$ time g++ -O2 -c -o quickbook.o quickbook.cpp
(endless loop, or takes a very long time)

According to g++ man page:

           -O2 turns on all optimization flags specified by -O.  It also turns
           on the following optimization flags: -fthread-jumps -fcrossjumping
           -foptimize-sibling-calls -fcse-follow-jumps  -fcse-skip-blocks
           -fgcse  -fgcse-lm -fexpensive-optimizations -fstrength-reduce -fre‐
           run-cse-after-loop  -frerun-loop-opt -fcaller-saves -fpeephole2
           -fschedule-insns  -fschedule-insns2 -fsched-interblock
           -fsched-spec -fregmove -fstrict-aliasing
           -fdelete-null-pointer-checks -freorder-blocks  -freorder-functions
           -falign-functions  -falign-jumps -falign-loops  -falign-labels
           -ftree-vrp -ftree-pre

So I tried adding on top of -O1, all optimisation turned on by O2, in order to 
find the one which causes the bug.
However, adding them all on top of -O1 does not trigger the bug:

[EMAIL PROTECTED]:/tmp$ time g++ -O1 -fthread-jumps -fcrossjumping
-foptimize-sibling-calls -fcse-follow-jumps  -fcse-skip-blocks -fgcse
-fgcse-lm -fexpensive-optimizations -fstrength-reduce -frerun-cse-after-
loop  -frerun-loop-opt -fcaller-saves -fpeephole2 -fschedule-insns
-fschedule-insns2 -fsched-interblock -fsched-spec -fregmove -fstrict-
aliasing -fdelete-null-pointer-checks -freorder-blocks  -freorder-
functions -falign-functions  -falign-jumps -falign-loops  -falign-labels
-ftree-vrp -ftree-pre  -c -o quickbook.o quickbook.cpp

real    0m39.420s
user    0m38.382s
sys     0m0.560s

Does it mean -O2 turns on optimisations that are not documented in g++
man page?

-- 
g++: infinite loop with -O3 while compiling Boost.Quickbook from Boost CVS
https://bugs.launchpad.net/bugs/82404
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