Merge master

cmake/warnings.cmake

@@ -23,6 +23,7 @@ if (COMPILER_CLANG)
     no_warning(zero-length-array)
     no_warning(c++98-compat-pedantic)
     no_warning(c++98-compat)
+    no_warning(c++20-compat) # Use constinit in C++20 without warnings
     no_warning(conversion)
     no_warning(ctad-maybe-unsupported) # clang 9+, linux-only
     no_warning(disabled-macro-expansion)

docs/en/sql-reference/functions/arithmetic-functions.md

@@ -55,9 +55,9 @@ Differs from ‘intDiv’ in that it returns zero when dividing by zero or when
 
 ## modulo(a, b), a % b operator
 
-Calculates the remainder after division.
+Calculates the remainder when dividing `a` by `b`.
-If arguments are floating-point numbers, they are pre-converted to integers by dropping the decimal portion.
+The result type is an integer if both inputs are integers. If one of the inputs is a floating-point number, the result is a floating-point number.
-The remainder is taken in the same sense as in C++. Truncated division is used for negative numbers.
+The remainder is computed like in C++. Truncated division is used for negative numbers.
 An exception is thrown when dividing by zero or when dividing a minimal negative number by minus one.
 
 ## moduloOrZero(a, b)

docs/en/sql-reference/functions/type-conversion-functions.md

@@ -1241,7 +1241,7 @@ Same as for [parseDateTime64BestEffort](#parsedatetime64besteffort), except that
 
 ## toLowCardinality
 
-Converts input parameter to the [LowCardianlity](../../sql-reference/data-types/lowcardinality.md) version of same data type.
+Converts input parameter to the [LowCardinality](../../sql-reference/data-types/lowcardinality.md) version of same data type.
 
 To convert data from the `LowCardinality` data type use the [CAST](#type_conversion_function-cast) function. For example, `CAST(x as String)`.
 

docs/ru/sql-reference/functions/arithmetic-functions.md

@@ -56,7 +56,7 @@ SELECT toTypeName(0), toTypeName(0 + 0), toTypeName(0 + 0 + 0), toTypeName(0 + 0
 ## modulo(a, b), оператор a % b {#modulo}
 
 Вычисляет остаток от деления.
-Если аргументы - числа с плавающей запятой, то они предварительно преобразуются в целые числа, путём отбрасывания дробной части.
+Тип результата - целое число, если оба аргумента - целые числа. Если один из аргументов является числом с плавающей точкой, результатом будет число с плавающей точкой.
 Берётся остаток в том же смысле, как это делается в C++. По факту, для отрицательных чисел, используется truncated division.
 При делении на ноль или при делении минимального отрицательного числа на минус единицу, кидается исключение.
 

docs/ru/sql-reference/functions/type-conversion-functions.md

@@ -1162,7 +1162,7 @@ FORMAT PrettyCompactMonoBlock;
 
 ## toLowCardinality {#tolowcardinality}
 
-Преобразует входные данные в версию [LowCardianlity](../data-types/lowcardinality.md) того же типа данных.
+Преобразует входные данные в версию [LowCardinality](../data-types/lowcardinality.md) того же типа данных.
 
 Чтобы преобразовать данные из типа `LowCardinality`, используйте функцию [CAST](#type_conversion_function-cast). Например, `CAST(x as String)`.
 

docs/zh/sql-reference/functions/arithmetic-functions.md

@@ -54,7 +54,7 @@ SELECT toTypeName(0), toTypeName(0 + 0), toTypeName(0 + 0 + 0), toTypeName(0 + 0
 ## modulo(a, b), a % b operator {#modulo}
 
 计算除法后的余数。
-如果参数是浮点数，则通过删除小数部分将它们预转换为整数。
+如果两个输入都是整数，结果类型是整数。如果其中一个输入是浮点数，则结果是浮点数。
 其余部分与C++中的含义相同。截断除法用于负数。
 除以零或将最小负数除以-1时抛出异常。
 

docs/zh/sql-reference/functions/type-conversion-functions.md

@@ -512,7 +512,7 @@ SELECT parseDateTimeBestEffort('10 20:19')
 
 ## toLowCardinality {#tolowcardinality}
 
-把输入值转换为[LowCardianlity](../data-types/lowcardinality.md)的相同类型的数据。
+把输入值转换为[LowCardinality](../data-types/lowcardinality.md)的相同类型的数据。
 
 如果要把`LowCardinality`类型的数据转换为其他类型，使用[CAST](#type_conversion_function-cast)函数。比如：`CAST(x as String)`。
 

src/Common/CurrentThread.cpp

@@ -43,13 +43,6 @@ ProfileEvents::Counters & CurrentThread::getProfileEvents()
     return current_thread ? current_thread->performance_counters : ProfileEvents::global_counters;
 }
 
-MemoryTracker * CurrentThread::getMemoryTracker()
-{
-    if (unlikely(!current_thread))
-        return nullptr;
-    return &current_thread->memory_tracker;
-}
-
 void CurrentThread::updateProgressIn(const Progress & value)
 {
     if (unlikely(!current_thread))

src/Common/CurrentThread.h

@@ -54,7 +54,12 @@ public:
     static void updatePerformanceCounters();
 
     static ProfileEvents::Counters & getProfileEvents();
-    static MemoryTracker * getMemoryTracker();
+    inline ALWAYS_INLINE static MemoryTracker * getMemoryTracker()
+    {
+        if (unlikely(!current_thread))
+            return nullptr;
+        return &current_thread->memory_tracker;
+    }
 
     /// Update read and write rows (bytes) statistics (used in system.query_thread_log)
     static void updateProgressIn(const Progress & value);

src/Common/FileCache.cpp

@@ -1061,14 +1061,13 @@ void FileCache::loadCacheInfoIntoMemory(std::lock_guard<std::mutex> & cache_lock
         fs::directory_iterator key_it{key_prefix_it->path()};
         for (; key_it != fs::directory_iterator(); ++key_it)
         {
-            key = Key(unhexUInt<UInt128>(key_it->path().filename().string().data()));
-
             if (!key_it->is_directory())
             {
                 LOG_WARNING(log, "Unexpected file: {}. Expected a directory", key_it->path().string());
                 continue;
             }
 
+            key = Key(unhexUInt<UInt128>(key_it->path().filename().string().data()));
             fs::directory_iterator offset_it{key_it->path()};
             for (; offset_it != fs::directory_iterator(); ++offset_it)
             {

src/Common/FileSegment.cpp

@@ -8,7 +8,6 @@
 #include <IO/WriteBufferFromString.h>
 #include <IO/Operators.h>
 #include <filesystem>
-#include <Common/FileCache.h>
 
 namespace CurrentMetrics
 {

src/Common/ThreadStatus.cpp

@@ -24,9 +24,7 @@ namespace ErrorCodes
     extern const int LOGICAL_ERROR;
 }
 
-
+thread_local ThreadStatus constinit * current_thread = nullptr;
-thread_local ThreadStatus * current_thread = nullptr;
-thread_local ThreadStatus * main_thread = nullptr;
 
 #if !defined(SANITIZER)
 namespace

src/Common/ThreadStatus.h

@@ -102,8 +102,16 @@ public:
 
 using ThreadGroupStatusPtr = std::shared_ptr<ThreadGroupStatus>;
 
-
+/**
-extern thread_local ThreadStatus * current_thread;
+ * We use **constinit** here to tell the compiler the current_thread variable is initialized.
+ * If we didn't help the compiler, then it would most likely add a check before every use of the variable to initialize it if needed.
+ * Instead it will trust that we are doing the right thing (and we do initialize it to nullptr) and emit more optimal code.
+ * This is noticeable in functions like CurrentMemoryTracker::free and CurrentMemoryTracker::allocImpl
+ * See also:
+ * - https://en.cppreference.com/w/cpp/language/constinit
+ * - https://github.com/ClickHouse/ClickHouse/pull/40078
+ */
+extern thread_local constinit ThreadStatus * current_thread;
 
 /** Encapsulates all per-thread info (ProfileEvents, MemoryTracker, query_id, query context, etc.).
   * The object must be created in thread function and destroyed in the same thread before the exit.