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

[via llvm-commits]

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@@ -1501,6 +1503,11 @@ class Allocator {
                 getPageSizeCached()),
         "scudo:ring_buffer");
     RawRingBuffer = reinterpret_cast<char *>(MemMap.getBase());
+    if (RawRingBuffer == nullptr) {
+      Printf("Failed to allocate allocation ring buffer of size %d",
+             getFlags()->allocation_ring_buffer_size);
+      return;
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ChiaHungDuan wrote:

Okay, I was thinking the case that if `allocation_ring_buffer_size` is too big, we may want to change a smaller number immediately instead of running the process for a while and then wonder why there's no stack stored. 

No strong opinion here

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