Description of problem:
gcc-4.3.0-8.i386

g++ -c -O2 -Werror=strict-aliasing -Wall may_alias.cxx
no errors, but

g++ -DINCLUDE_VECTOR -c -O2 -Werror=strict-aliasing -Wall may_alias.cxx
may_alias.cxx: In function ‘bool operator>>=(const Any&, long int&)’:
may_alias.cxx:30: error: dereferencing type-punned pointer will break
strict-aliasing rules
where INCLUDE_VECTOR just includes <vector>

strangely the effect is seen on the "double" but not on the "long" equivalent.
Demo attached