diff --git a/compiler-rt/lib/scudo/standalone/tests/combined_test.cpp b/compiler-rt/lib/scudo/standalone/tests/combined_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/combined_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/combined_test.cpp
@@ -154,9 +154,10 @@
   for (scudo::uptr AlignLog = MinAlignLog; AlignLog <= 16U; AlignLog++) {
     const scudo::uptr Align = 1U << AlignLog;
     for (scudo::sptr Delta = -32; Delta <= 32; Delta++) {
-      if (static_cast<scudo::sptr>(1U << SizeLog) + Delta < 0)
+      if ((1LL << SizeLog) + Delta < 0)
         continue;
-      const scudo::uptr Size = (1U << SizeLog) + Delta;
+      const scudo::uptr Size =
+          static_cast<scudo::uptr>((1LL << SizeLog) + Delta);
       void *P = Allocator->allocate(Size, Origin, Align);
       EXPECT_NE(P, nullptr);
       EXPECT_TRUE(Allocator->isOwned(P));
@@ -333,7 +334,8 @@
   const char Marker = 0xab;
   memset(P, Marker, ReallocSize);
   for (scudo::sptr Delta = -32; Delta < 32; Delta += 8) {
-    const scudo::uptr NewSize = ReallocSize + Delta;
+    const scudo::uptr NewSize =
+        static_cast<scudo::uptr>(static_cast<scudo::sptr>(ReallocSize) + Delta);
     void *NewP = Allocator->reallocate(P, NewSize);
     EXPECT_EQ(NewP, P);
     for (scudo::uptr I = 0; I < ReallocSize - 32; I++)
@@ -355,11 +357,13 @@
     std::vector<void *> V;
     for (scudo::uptr I = 0; I < 64U; I++)
       V.push_back(Allocator->allocate(
-          rand() % (TypeParam::Primary::SizeClassMap::MaxSize / 2U), Origin));
+          static_cast<scudo::uptr>(std::rand()) %
+              (TypeParam::Primary::SizeClassMap::MaxSize / 2U),
+          Origin));
     Allocator->disable();
     Allocator->iterateOverChunks(
         0U, static_cast<scudo::uptr>(SCUDO_MMAP_RANGE_SIZE - 1),
-        [](uintptr_t Base, size_t Size, void *Arg) {
+        [](uintptr_t Base, UNUSED size_t Size, void *Arg) {
           std::vector<void *> *V = reinterpret_cast<std::vector<void *> *>(Arg);
           void *P = reinterpret_cast<void *>(Base);
           EXPECT_NE(std::find(V->begin(), V->end(), P), V->end());
@@ -444,7 +448,9 @@
   std::vector<void *> V;
   for (scudo::uptr I = 0; I < 64U; I++)
     V.push_back(Allocator->allocate(
-        rand() % (TypeParam::Primary::SizeClassMap::MaxSize / 2U), Origin));
+        static_cast<scudo::uptr>(std::rand()) %
+            (TypeParam::Primary::SizeClassMap::MaxSize / 2U),
+        Origin));
   for (auto P : V)
     Allocator->deallocate(P, Origin);
 
@@ -463,7 +469,9 @@
   std::vector<void *> V;
   for (scudo::uptr I = 0; I < 64U; I++)
     V.push_back(Allocator->allocate(
-        rand() % (TypeParam::Primary::SizeClassMap::MaxSize / 2U), Origin));
+        static_cast<scudo::uptr>(std::rand()) %
+            (TypeParam::Primary::SizeClassMap::MaxSize / 2U),
+        Origin));
   for (auto P : V)
     Allocator->deallocate(P, Origin);
 
@@ -494,7 +502,7 @@
       }
       std::vector<std::pair<void *, scudo::uptr>> V;
       for (scudo::uptr I = 0; I < 256U; I++) {
-        const scudo::uptr Size = std::rand() % 4096U;
+        const scudo::uptr Size = static_cast<scudo::uptr>(std::rand()) % 4096U;
         void *P = Allocator->allocate(Size, Origin);
         // A region could have ran out of memory, resulting in a null P.
         if (P)
@@ -727,17 +735,17 @@
 
   // Regression test: make realloc-in-place happen at the very right end of a
   // mapped region.
-  constexpr int nPtrs = 10000;
-  for (int i = 1; i < 32; ++i) {
+  constexpr size_t nPtrs = 10000;
+  for (scudo::uptr i = 1; i < 32; ++i) {
     scudo::uptr Size = 16 * i - 1;
     std::vector<void *> Ptrs;
-    for (int i = 0; i < nPtrs; ++i) {
+    for (size_t i = 0; i < nPtrs; ++i) {
       void *P = Allocator->allocate(Size, Origin);
       P = Allocator->reallocate(P, Size + 1);
       Ptrs.push_back(P);
     }
 
-    for (int i = 0; i < nPtrs; ++i)
+    for (size_t i = 0; i < nPtrs; ++i)
       Allocator->deallocate(Ptrs[i], Origin);
   }
 }
diff --git a/compiler-rt/lib/scudo/standalone/tests/memtag_test.cpp b/compiler-rt/lib/scudo/standalone/tests/memtag_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/memtag_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/memtag_test.cpp
@@ -76,12 +76,16 @@
 }
 
 TEST_F(MemtagTest, ExtractTag) {
+// The test is already skipped on anything other than 64 bit. But
+// compiling on 32 bit leads to warnings/errors, so skip compiling the test.
+#if defined(__LP64__)
   uptr Tags = 0;
   // Try all value for the top byte and check the tags values are in the
   // expected range.
   for (u64 Top = 0; Top < 0x100; ++Top)
     Tags = Tags | (1u << extractTag(Addr | (Top << 56)));
   EXPECT_EQ(0xffffull, Tags);
+#endif
 }
 
 TEST_F(MemtagDeathTest, AddFixedTag) {
@@ -121,10 +125,14 @@
 }
 
 TEST_F(MemtagTest, SelectRandomTagWithMask) {
+// The test is already skipped on anything other than 64 bit. But
+// compiling on 32 bit leads to warnings/errors, so skip compiling the test.
+#if defined(__LP64__)
   for (uptr j = 0; j < 32; ++j) {
     for (uptr i = 0; i < 1000; ++i)
       EXPECT_NE(j, extractTag(selectRandomTag(Addr, 1ull << j)));
   }
+#endif
 }
 
 TEST_F(MemtagDeathTest, SKIP_NO_DEBUG(LoadStoreTagUnaligned)) {
@@ -158,6 +166,9 @@
 }
 
 TEST_F(MemtagTest, StoreTags) {
+// The test is already skipped on anything other than 64 bit. But
+// compiling on 32 bit leads to warnings/errors, so skip compiling the test.
+#if defined(__LP64__)
   const uptr MaxTaggedSize = 4 * archMemoryTagGranuleSize();
   for (uptr Size = 0; Size <= MaxTaggedSize; ++Size) {
     uptr NoTagBegin = Addr + archMemoryTagGranuleSize();
@@ -186,6 +197,7 @@
     // Reset tags without using StoreTags.
     MemMap.releasePagesToOS(Addr, BufferSize);
   }
+#endif
 }
 
 } // namespace scudo
diff --git a/compiler-rt/lib/scudo/standalone/tests/primary_test.cpp b/compiler-rt/lib/scudo/standalone/tests/primary_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/primary_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/primary_test.cpp
@@ -253,7 +253,8 @@
   Cache.init(nullptr, Allocator.get());
   std::vector<std::pair<scudo::uptr, void *>> V;
   for (scudo::uptr I = 0; I < 64U; I++) {
-    const scudo::uptr Size = std::rand() % Primary::SizeClassMap::MaxSize;
+    const scudo::uptr Size =
+        static_cast<scudo::uptr>(std::rand()) % Primary::SizeClassMap::MaxSize;
     const scudo::uptr ClassId = Primary::SizeClassMap::getClassIdBySize(Size);
     void *P = Cache.allocate(ClassId);
     V.push_back(std::make_pair(ClassId, P));
@@ -300,8 +301,8 @@
           Cv.wait(Lock);
       }
       for (scudo::uptr I = 0; I < 256U; I++) {
-        const scudo::uptr Size =
-            std::rand() % Primary::SizeClassMap::MaxSize / 4;
+        const scudo::uptr Size = static_cast<scudo::uptr>(std::rand()) %
+                                 Primary::SizeClassMap::MaxSize / 4;
         const scudo::uptr ClassId =
             Primary::SizeClassMap::getClassIdBySize(Size);
         void *P = Cache.allocate(ClassId);
diff --git a/compiler-rt/lib/scudo/standalone/tests/release_test.cpp b/compiler-rt/lib/scudo/standalone/tests/release_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/release_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/release_test.cpp
@@ -134,8 +134,9 @@
     // Strip trailing '.'-pages before comparing the results as they are not
     // going to be reported to range_recorder anyway.
     const char *LastX = strrchr(TestCase, 'x');
-    std::string Expected(TestCase,
-                         LastX == nullptr ? 0 : (LastX - TestCase + 1));
+    std::string Expected(
+        TestCase,
+        LastX == nullptr ? 0U : static_cast<size_t>(LastX - TestCase + 1));
     EXPECT_STREQ(Expected.c_str(), Recorder.ReportedPages.c_str());
   }
 }
diff --git a/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp b/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp
@@ -136,10 +136,10 @@
          AlignLog++) {
       const scudo::uptr Align = 1U << AlignLog;
       for (scudo::sptr Delta = -128; Delta <= 128; Delta += 8) {
-        if (static_cast<scudo::sptr>(1U << SizeLog) + Delta <= 0)
+        if ((1LL << SizeLog) + Delta <= 0)
           continue;
-        const scudo::uptr UserSize =
-            scudo::roundUp((1U << SizeLog) + Delta, MinAlign);
+        const scudo::uptr UserSize = scudo::roundUp(
+            static_cast<scudo::uptr>((1LL << SizeLog) + Delta), MinAlign);
         const scudo::uptr Size =
             HeaderSize + UserSize + (Align > MinAlign ? Align - HeaderSize : 0);
         void *P = Allocator->allocate(Options, Size, Align);
@@ -160,7 +160,8 @@
   std::vector<void *> V;
   const scudo::uptr PageSize = scudo::getPageSizeCached();
   for (scudo::uptr I = 0; I < 32U; I++)
-    V.push_back(Allocator->allocate(Options, (std::rand() % 16) * PageSize));
+    V.push_back(Allocator->allocate(
+        Options, (static_cast<scudo::uptr>(std::rand()) % 16U) * PageSize));
   auto Lambda = [&V](scudo::uptr Block) {
     EXPECT_NE(std::find(V.begin(), V.end(), reinterpret_cast<void *>(Block)),
               V.end());
@@ -215,8 +216,9 @@
     }
     for (scudo::uptr I = 0; I < 128U; I++) {
       // Deallocate 75% of the blocks.
-      const bool Deallocate = (rand() & 3) != 0;
-      void *P = Allocator->allocate(Options, (std::rand() % 16) * PageSize);
+      const bool Deallocate = (std::rand() & 3) != 0;
+      void *P = Allocator->allocate(
+          Options, (static_cast<scudo::uptr>(std::rand()) % 16U) * PageSize);
       if (Deallocate)
         Allocator->deallocate(Options, P);
       else
diff --git a/compiler-rt/lib/scudo/standalone/tests/tsd_test.cpp b/compiler-rt/lib/scudo/standalone/tests/tsd_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/tsd_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/tsd_test.cpp
@@ -38,7 +38,7 @@
 
   void unmapTestOnly() { TSDRegistry.unmapTestOnly(this); }
   void initCache(CacheT *Cache) { *Cache = {}; }
-  void commitBack(scudo::TSD<MockAllocator> *TSD) {}
+  void commitBack(UNUSED scudo::TSD<MockAllocator> *TSD) {}
   TSDRegistryT *getTSDRegistry() { return &TSDRegistry; }
   void callPostInitCallback() {}
 
diff --git a/compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp b/compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp
@@ -267,7 +267,7 @@
 
 TEST(ScudoWrappersCTest, OtherAlloc) {
 #if HAVE_PVALLOC
-  const size_t PageSize = sysconf(_SC_PAGESIZE);
+  const size_t PageSize = static_cast<size_t>(sysconf(_SC_PAGESIZE));
 
   void *P = pvalloc(Size);
   EXPECT_NE(P, nullptr);
@@ -329,7 +329,7 @@
 static uintptr_t BoundaryP;
 static size_t Count;
 
-static void callback(uintptr_t Base, size_t Size, void *Arg) {
+static void callback(uintptr_t Base, UNUSED size_t Size, UNUSED void *Arg) {
   if (scudo::archSupportsMemoryTagging()) {
     Base = scudo::untagPointer(Base);
     BoundaryP = scudo::untagPointer(BoundaryP);
@@ -343,7 +343,7 @@
 // aligned on a page, then run the malloc_iterate on both the pages that the
 // block is a boundary for. It must only be seen once by the callback function.
 TEST(ScudoWrappersCTest, MallocIterateBoundary) {
-  const size_t PageSize = sysconf(_SC_PAGESIZE);
+  const size_t PageSize = static_cast<size_t>(sysconf(_SC_PAGESIZE));
 #if SCUDO_ANDROID
   // Android uses a 16 byte alignment for both 32 bit and 64 bit.
   const size_t BlockDelta = 16U;
@@ -461,7 +461,7 @@
 static pthread_cond_t Conditional = PTHREAD_COND_INITIALIZER;
 static bool Ready;
 
-static void *enableMalloc(void *Unused) {
+static void *enableMalloc(UNUSED void *Unused) {
   // Initialize the allocator for this thread.
   void *P = malloc(Size);
   EXPECT_NE(P, nullptr);
diff --git a/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp b/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp
@@ -103,7 +103,7 @@
       Cv.wait(Lock);
   }
   for (size_t I = 0; I < 256U; I++) {
-    const size_t N = std::rand() % 128U;
+    const size_t N = static_cast<size_t>(std::rand()) % 128U;
     uintptr_t *P = new uintptr_t[N];
     if (P) {
       memset(P, 0x42, sizeof(uintptr_t) * N);