[compiler-rt] [msan] Mark allocator padding as uninitialized, with new origin tag (PR #157187)

[Vitaly Buka via llvm-commits]

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@@ -90,6 +90,11 @@ static void DescribeOrigin(u32 id) {
         Printf("  %sVirtual table ptr was destroyed%s\n", d.Origin(),
                d.Default());
         break;
+      case STACK_TRACE_TAG_ALLOC_PADDING:
+        Printf(
+            "  %sUninitialized value was created by heap allocator padding%s\n",
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vitalybuka wrote:

something: Uninitialized value is outside of heap allocation

https://github.com/llvm/llvm-project/pull/157187