[compiler-rt] [ASan] Honor `allocator_may_return_null` when set through user-function and fix large alloc edge case (PR #117929)

[via llvm-commits]

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@@ -0,0 +1,34 @@
+// RUN: %clangxx_asan -O0 %s -o %t
+// RUN: %env_asan_opts=allocator_may_return_null=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-ABORT
+// RUN: %env_asan_opts=allocator_may_return_null=1 %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-RETURN_NULL
+
+// RUN: %clangxx_asan -O0 %s -o %t -DUSER_FUNCTION
+// RUN: %env_asan_opts=allocator_may_return_null=1 %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-RETURN_NULL
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zmodem wrote:

The `%env_asan_opts=allocator_may_return_null=1` part seems redundant here, and defeating the purpose of defining `__asan_default_options`.

https://github.com/llvm/llvm-project/pull/117929