VC10 compiler warnings 'unreachable code' when building with link-time code generation

When building OCCT with VC10 with compiler option /GL (global optimization) and linker option /LTCG (link-time code generation), it gives the following warnings on unreachable code:

warning C4702: unreachable code d:\abv\occt\occt\src\draw\draw.cxx 404
warning C4702: unreachable code d:\abv\occt\occt\src\intstart\intstart_searchonboundaries.gxx 944