Remove unused-but-set variables in velox/common/caching/tests/SsdFile…

…Test.cpp +3 (facebookincubator#9907)

Summary:
Pull Request resolved: facebookincubator#9907

This diff removes a variable that was set, but which was not used.

LLVM-15 has a warning `-Wunused-but-set-variable` which we treat as an error because it's so often diagnostic of a code issue. Unused but set variables often indicate a programming mistake, but can also just be unnecessary cruft that harms readability and performance.

Removing this variable will not change how your code works, but the unused variable may indicate your code isn't working the way you thought it was. If you feel the diff needs changes before landing, **please commandeer** and make appropriate changes: there are hundreds of these and responding to them individually is challenging.

For questions/comments, contact r-barnes.

 - If you approve of this diff, please use the "Accept & Ship" button :-)

Reviewed By: palmje, mbasmanova

Differential Revision: D57685875

fbshipit-source-id: 4d54d842f4e98bb878cfb8f381e58cc2da6a4e58

velox/common/caching/tests/SsdFileTest.cpp

@@ -311,7 +311,6 @@ TEST_F(SsdFileTest, writeAndRead) {
 
   // We check howmany entries are found. The earliest writes will have been
   // evicted. We read back the found entries and check their contents.
-  int32_t numFound = 0;
   for (auto& entry : allEntries) {
     std::vector<CachePin> pins;
 
@@ -325,7 +324,6 @@ TEST_F(SsdFileTest, writeAndRead) {
       ssdPins.push_back(
           ssdFile_->find(RawFileCacheKey{fileName_.id(), entry.key.offset}));
       if (!ssdPins.back().empty()) {
-        ++numFound;
         ssdFile_->load(ssdPins, pins);
         checkContents(pins[0].entry()->data(), pins[0].entry()->size());
       }

velox/common/memory/MallocAllocator.cpp

@@ -138,7 +138,7 @@ bool MallocAllocator::allocateContiguousImpl(
   } else {
     VELOX_CHECK_LE(numPages, maxPages);
   }
-  MachinePageCount numCollateralPages = 0;
+  [[maybe_unused]] MachinePageCount numCollateralPages = 0;
   if (collateral != nullptr) {
     numCollateralPages =
         freeNonContiguous(*collateral) / AllocationTraits::kPageSize;

velox/common/memory/tests/ByteStreamTest.cpp

@@ -101,7 +101,7 @@ TEST_F(ByteStreamTest, inputStream) {
   uint8_t* const kFakeBuffer = reinterpret_cast<uint8_t*>(this);
   std::vector<ByteRange> byteRanges;
   size_t totalBytes{0};
-  size_t lastRangeEnd;
+  [[maybe_unused]] size_t lastRangeEnd;
   for (int32_t i = 0; i < 32; ++i) {
     byteRanges.push_back(ByteRange{kFakeBuffer, 4096 + i, 0});
     totalBytes += 4096 + i;