[compiler-rt] [scudo] Handle failed mmap for allocation ring buffer (PR #71817)

[Fabio D'Urso via llvm-commits]

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@@ -1501,6 +1503,11 @@ class Allocator {
                 getPageSizeCached()),
         "scudo:ring_buffer");
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fabio-d wrote:

Oh, and you may want to just check the return value of `map` (it returns a bool) instead of testing if `getBase()` is a nullptr later

https://github.com/llvm/llvm-project/pull/71817