[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:

Shouldn't this call include the `MAP_ALLOWNOMEM` flag? (it should be possible to get a `nullptr` if you don't pass this flag - if you've seen one without it, there might some hidden bug elsewhere)

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