[Bug libstdc++/32261] Thread race segfault in std::string::append with -O and -s

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=32261
Bug 32261 depends on bug 33394, which changed state.

Bug 33394 Summary: Add test case for Thread race segfault in 
std::string::append with -O and -s
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33394

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED