[libc] [llvm] [libc] Migrate unistd tests to use ErrnoCheckingTest. (PR #132067)

[via llvm-commits]

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@@ -41,10 +41,12 @@
 // they all provide.
 
 #define ASSERT_ERRNO_EQ(VAL)                                                   \
-  ASSERT_EQ(VAL, static_cast<int>(LIBC_NAMESPACE::libc_errno))
+  ASSERT_EQ(VAL, static_cast<int>(LIBC_NAMESPACE::libc_errno));                \
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lntue wrote:

can you wrap them inside `do { } while (0)` instead?

https://github.com/llvm/llvm-project/pull/132067