[Bug c++/55171] [4.7/4.8 Regression] incorrect virtual thunk on mingw

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55171

--- Comment #8 from Kai Tietz <ktietz at gcc dot gnu.org> 2012-11-24 12:54:40 UTC ---
The pattern is

movl    4(%esp), %eax
movl    (%eax), %eax
addl    -16(%eax), %eax

As here the saved this-pointer in %eax gets clobbered.