[compiler-rt] [scudo] Add -Wconversion for tests and clean-up warnings. (PR #66147)

[Mitch Phillips via llvm-commits]

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@@ -54,7 +54,7 @@ void checkMemoryTaggingMaybe(AllocatorT *Allocator, void *P, scudo::uptr Size,
     EXPECT_DEATH(
         {
           disableDebuggerdMaybe();
-          reinterpret_cast<char *>(P)[-1] = 0xaa;
+          reinterpret_cast<char *>(P)[-1] = '\xaa';
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hctim wrote:

Let's just use 'A' (this is just a crash test, so the value doens't matter).

https://github.com/llvm/llvm-project/pull/66147