[PATCH] Optional support for dynamic Asan runtime

[Yury Gribov]

  > Still not sure how to detect static/shared rt conflicts though.

  One option would be to export some marker from executable linked with static libasan (e.g. __local_asan_preinit symbol) and then check if it's present via dlsym() in __asan_init if ASAN_DYNAMIC is defined.

http://llvm-reviews.chandlerc.com/D3042