Jason Molenda 1e7ecd3e64 Fix a race condition in FuncUnwinders where the mutex was being
acquired only after checking if the ivar shared pointer was already
filled in.  But when I assign an UnwindPlan object to the shared
pointer, I assign an empty object and then fill it in.  That leaves
a window where another thread could get the shared pointer to the
empty (but quickly being-filled-in) object and lead to a crash.

Also two changes from Greg for correctness on the TestMultipleDebuggers
test case.

<rdar://problem/30564102> 

llvm-svn: 296084
2017-02-24 03:35:46 +00:00
..