[compiler-rt] [rtsan] Support legacy pthread_cond variables (PR #152947)

[Chris Apple via llvm-commits]

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@@ -46,12 +46,44 @@
 
 using namespace __sanitizer;
 
+#if defined(__x86_64__) || defined(__mips__) || SANITIZER_PPC64V1 ||           \
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cjappl wrote:

100% Agreed. My thoughts were: "Try to fix the issue in as straightforward way as possible, then come back and abstract". (aka follow up with some NFC reshuffle)

I don't want to go messing around in the other sanitizers until we are sure this is a fix that works.

https://github.com/llvm/llvm-project/pull/152947