[llvm] llvm-cov: Fix a grammar error (PR #179450)

[via llvm-commits]

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@@ -472,7 +472,10 @@ std::unique_ptr<CoverageMapping> CodeCoverageTool::load() {
   auto Coverage = std::move(CoverageOrErr.get());
   unsigned Mismatched = Coverage->getMismatchedCount();
   if (Mismatched) {
-    warning(Twine(Mismatched) + " functions have mismatched data");
+    if Mismatched
+      == 1 warning(Twine(Mismatched) + " function has mismatched data");
+    else
+      warning(Twine(Mismatched) + " functions have mismatched data");
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cerdelen wrote:

In the link you provided it also says to include a unit test.

Trying to locate unit tests for tools llvm-cov it seems there is none, as there is no folder llvm-cov in llvm/unittests/tools.

https://github.com/llvm/llvm-project/pull/179450