[clang] [compiler-rt] [ASan] Document define to disable container overflow checks at compile time. (PR #163468)

[Louis Dionne via cfe-commits]

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@@ -164,6 +164,19 @@ To summarize: ``-fsanitize-address-use-after-return=<mode>``
   * ``always``: Enables detection of UAR errors in all cases. (reduces code
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ldionne wrote:

Not attached to this line: there seems to be a stray `The recommended pattern is:` in the PR description.

https://github.com/llvm/llvm-project/pull/163468