[compiler-rt] [sanitizer_common][lsan] Keep the original allocation alive when realloc fails (PR #222849)

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``````````bash
git-clang-format --diff origin/main HEAD --extensions h,cpp,c -- compiler-rt/test/lsan/TestCases/Linux/realloc_failure_keeps_original.cpp compiler-rt/lib/lsan/lsan_allocator.cpp compiler-rt/lib/sanitizer_common/sanitizer_allocator_combined.h compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp compiler-rt/test/lsan/TestCases/realloc_zero.c --diff_from_common_commit
``````````

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``````````diff
diff --git a/compiler-rt/lib/lsan/lsan_allocator.cpp b/compiler-rt/lib/lsan/lsan_allocator.cpp
index 8433626f6..16a27658a 100644
--- a/compiler-rt/lib/lsan/lsan_allocator.cpp
+++ b/compiler-rt/lib/lsan/lsan_allocator.cpp
@@ -140,11 +140,11 @@ void *Reallocate(const StackTrace &stack, void *p, uptr new_size,
     return nullptr;
   }
   CHECK(allocator.PointerIsMine(p));
-  ChunkMetadata *m = Metadata(p);
+  ChunkMetadata* m = Metadata(p);
   CHECK(m);
   const uptr old_size = m->requested_size;
   // Allocate first: on failure p must be left untouched.
-  void *new_p = Allocate(stack, new_size, alignment, false);
+  void* new_p = Allocate(stack, new_size, alignment, false);
   if (!new_p)
     return nullptr;
   internal_memcpy(new_p, p, Min(new_size, old_size));
diff --git a/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp b/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp
index 21d9e4180..77753b75f 100644
--- a/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp
+++ b/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp
@@ -755,20 +755,20 @@ void TestCombinedAllocator(uptr premapped_heap = 0) {
   // size-plus-alignment check inside Allocate(), which logs a warning.
   {
     const uptr kSize = 128;
-    char *p = reinterpret_cast<char *>(a->Allocate(&cache, kSize, 1));
+    char* p = reinterpret_cast<char*>(a->Allocate(&cache, kSize, 1));
     ASSERT_NE(p, nullptr);
-    uptr *meta = reinterpret_cast<uptr *>(a->GetMetaData(p));
+    uptr* meta = reinterpret_cast<uptr*>(a->GetMetaData(p));
     *meta = kSize;
     internal_memset(p, 'x', kSize);
 
     EXPECT_EQ(a->Reallocate(&cache, p, (uptr)-1, 1), nullptr);
 
     // These hold even for a released chunk; the loop below is what detects it.
-    EXPECT_EQ(*reinterpret_cast<uptr *>(a->GetMetaData(p)), kSize);
+    EXPECT_EQ(*reinterpret_cast<uptr*>(a->GetMetaData(p)), kSize);
     EXPECT_EQ(p[0], 'x');
     EXPECT_EQ(p[kSize - 1], 'x');
 
-    void *others[8];
+    void* others[8];
     for (uptr i = 0; i < ARRAY_SIZE(others); i++) {
       others[i] = a->Allocate(&cache, kSize, 1);
       EXPECT_NE(others[i], p);
@@ -785,17 +785,17 @@ void TestCombinedAllocator(uptr premapped_heap = 0) {
   // leaves p unmapped, so assert ownership before reading through it.
   {
     const uptr kLarge = 1 << 20;
-    void *p = a->Allocate(&cache, kLarge, 1);
+    void* p = a->Allocate(&cache, kLarge, 1);
     ASSERT_NE(p, nullptr);
     if (!a->FromPrimary(p)) {
-      uptr *meta = reinterpret_cast<uptr *>(a->GetMetaData(p));
+      uptr* meta = reinterpret_cast<uptr*>(a->GetMetaData(p));
       *meta = kLarge;
 
       EXPECT_EQ(a->Reallocate(&cache, p, (uptr)-1, 1), nullptr);
 
       ASSERT_TRUE(a->PointerIsMine(p));
       EXPECT_EQ(a->GetBlockBegin(p), p);
-      EXPECT_EQ(*reinterpret_cast<uptr *>(a->GetMetaData(p)), kLarge);
+      EXPECT_EQ(*reinterpret_cast<uptr*>(a->GetMetaData(p)), kLarge);
       *meta = 0;
     }
     a->Deallocate(&cache, p);

``````````

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https://github.com/llvm/llvm-project/pull/222849