abort instead of __builtin_unreachable in debug builds

base/base/defines.h

@@ -123,11 +123,15 @@
 ///     - tries to print failed assertion into server log
 /// It can be used for all assertions except heavy ones.
 /// Heavy assertions (that run loops or call complex functions) are allowed in debug builds only.
+/// Also it makes sense to call abort() instead of __builtin_unreachable() in debug builds,
+/// because SIGABRT is easier to debug than SIGTRAP (the second one makes gdb crazy)
 #if !defined(chassert)
     #if defined(ABORT_ON_LOGICAL_ERROR)
         #define chassert(x) static_cast<bool>(x) ? void(0) : abortOnFailedAssertion(#x)
+        #define UNREACHABLE() abort()
     #else
         #define chassert(x) ((void)0)
+        #define UNREACHABLE() __builtin_unreachable()
     #endif
 #endif
 

base/base/safeExit.cpp

@@ -11,7 +11,7 @@
     /// Thread sanitizer tries to do something on exit that we don't need if we want to exit immediately,
     /// while connection handling threads are still run.
     (void)syscall(SYS_exit_group, code);
-    __builtin_unreachable();
+    UNREACHABLE();
 #else
     _exit(code);
 #endif

programs/main.cpp

@@ -219,7 +219,7 @@ auto instructionFailToString(InstructionFail fail)
         case InstructionFail::AVX512:
             ret("AVX512");
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Access/AccessEntityIO.cpp

@@ -145,7 +145,7 @@ AccessEntityPtr deserializeAccessEntity(const String & definition, const String
     {
         e.addMessage("Could not parse " + file_path);
         e.rethrow();
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 

src/Access/AccessRights.cpp

@@ -209,7 +209,7 @@ namespace
             case TABLE_LEVEL: return AccessFlags::allFlagsGrantableOnTableLevel();
             case COLUMN_LEVEL: return AccessFlags::allFlagsGrantableOnColumnLevel();
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 

src/Access/IAccessStorage.cpp

@@ -215,7 +215,7 @@ std::vector<UUID> IAccessStorage::insert(const std::vector<AccessEntityPtr> & mu
             e.addMessage("After successfully inserting {}/{}: {}", successfully_inserted.size(), multiple_entities.size(), successfully_inserted_str);
         }
         e.rethrow();
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 
@@ -319,7 +319,7 @@ std::vector<UUID> IAccessStorage::remove(const std::vector<UUID> & ids, bool thr
             e.addMessage("After successfully removing {}/{}: {}", removed_names.size(), ids.size(), removed_names_str);
         }
         e.rethrow();
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 
@@ -416,7 +416,7 @@ std::vector<UUID> IAccessStorage::update(const std::vector<UUID> & ids, const Up
             e.addMessage("After successfully updating {}/{}: {}", names_of_updated.size(), ids.size(), names_of_updated_str);
         }
         e.rethrow();
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 

src/AggregateFunctions/AggregateFunctionGroupArray.h

@@ -56,7 +56,7 @@ static constexpr const char * getNameByTrait()
         return "groupArraySample";
     // else if (Trait::sampler == Sampler::DETERMINATOR) // TODO
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename T>

src/AggregateFunctions/AggregateFunctionSequenceNextNode.h

@@ -395,7 +395,7 @@ public:
                         break;
                 return (i == events_size) ? base - i : unmatched_idx;
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     void insertResultInto(AggregateDataPtr __restrict place, IColumn & to, Arena *) const override

src/AggregateFunctions/AggregateFunctionStatisticsSimple.h

@@ -114,7 +114,7 @@ public:
             return "covarSamp";
         if constexpr (StatFunc::kind == StatisticsFunctionKind::corr)
             return "corr";
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     DataTypePtr getReturnType() const override

src/AggregateFunctions/AggregateFunctionSum.h

@@ -407,7 +407,7 @@ public:
             return "sumWithOverflow";
         else if constexpr (Type == AggregateFunctionTypeSumKahan)
             return "sumKahan";
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     explicit AggregateFunctionSum(const DataTypes & argument_types_)

src/AggregateFunctions/AggregateFunctionUniqCombined.cpp

@@ -131,7 +131,7 @@ namespace
                 return createAggregateFunctionWithHashType<20>(use_64_bit_hash, argument_types, params);
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
 }

src/Common/DateLUTImpl.cpp

@@ -30,7 +30,7 @@ UInt8 getDayOfWeek(const cctz::civil_day & date)
         case cctz::weekday::saturday:   return 6;
         case cctz::weekday::sunday:     return 7;
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 }

src/Common/HashTable/Hash.h

@@ -119,7 +119,7 @@ inline UInt32 updateWeakHash32(const DB::UInt8 * pos, size_t size, DB::UInt32 up
                 __builtin_memcpy(&value, pos, 7);
                 break;
             default:
-                __builtin_unreachable();
+                UNREACHABLE();
         }
 
         reinterpret_cast<unsigned char *>(&value)[7] = size;
@@ -194,8 +194,7 @@ inline size_t DefaultHash64(T key)
             static_cast<UInt64>(key >> 128) ^
             static_cast<UInt64>(key >> 256));
     }
-    assert(false);
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename T>
@@ -454,8 +453,7 @@ struct IntHash32
             return intHash32<salt>(u.out);
         }
 
-        assert(false);
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 };
 

src/Common/HashTable/HashTable.h

@@ -353,11 +353,11 @@ struct HashTableFixedGrower
 
     size_t bufSize() const               { return 1ULL << key_bits; }
     size_t place(size_t x) const         { return x; }
-    /// You could write __builtin_unreachable(), but the compiler does not optimize everything, and it turns out less efficiently.
+    /// You could write UNREACHABLE(), but the compiler does not optimize everything, and it turns out less efficiently.
     size_t next(size_t pos) const        { return pos + 1; }
     bool overflow(size_t /*elems*/) const { return false; }
 
-    void increaseSize() { __builtin_unreachable(); }
+    void increaseSize() { UNREACHABLE(); }
     void set(size_t /*num_elems*/) {}
     void setBufSize(size_t /*buf_size_*/) {}
 };

src/Common/IntervalKind.cpp

@@ -26,7 +26,7 @@ Int32 IntervalKind::toAvgSeconds() const
         case IntervalKind::Quarter: return 7889238; /// Exactly 1/4 of a year.
         case IntervalKind::Year: return 31556952;   /// The average length of a Gregorian year is equal to 365.2425 days
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 Float64 IntervalKind::toSeconds() const
@@ -52,7 +52,7 @@ Float64 IntervalKind::toSeconds() const
         default:
             throw Exception("Not possible to get precise number of seconds in non-precise interval", ErrorCodes::BAD_ARGUMENTS);
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 bool IntervalKind::isFixedLength() const
@@ -71,7 +71,7 @@ bool IntervalKind::isFixedLength() const
         case IntervalKind::Quarter:
         case IntervalKind::Year: return false;
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 IntervalKind IntervalKind::fromAvgSeconds(Int64 num_seconds)
@@ -113,7 +113,7 @@ const char * IntervalKind::toKeyword() const
         case IntervalKind::Quarter: return "QUARTER";
         case IntervalKind::Year: return "YEAR";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 
@@ -133,7 +133,7 @@ const char * IntervalKind::toLowercasedKeyword() const
         case IntervalKind::Quarter: return "quarter";
         case IntervalKind::Year: return "year";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 
@@ -164,7 +164,7 @@ const char * IntervalKind::toDateDiffUnit() const
         case IntervalKind::Year:
             return "year";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 
@@ -195,7 +195,7 @@ const char * IntervalKind::toNameOfFunctionToIntervalDataType() const
         case IntervalKind::Year:
             return "toIntervalYear";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 
@@ -229,7 +229,7 @@ const char * IntervalKind::toNameOfFunctionExtractTimePart() const
         case IntervalKind::Year:
             return "toYear";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Common/TargetSpecific.cpp

@@ -1,3 +1,4 @@
+#include <base/defines.h>
 #include <Common/TargetSpecific.h>
 
 #include <Common/CpuId.h>
@@ -42,7 +43,7 @@ String toString(TargetArch arch)
         case TargetArch::AVX512VBMI: return "avx512vbmi";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 }

src/Common/ThreadProfileEvents.cpp

@@ -76,7 +76,7 @@ const char * TasksStatsCounters::metricsProviderString(MetricsProvider provider)
         case MetricsProvider::Netlink:
             return "netlink";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 bool TasksStatsCounters::checkIfAvailable()

src/Common/ZooKeeper/IKeeper.cpp

@@ -112,7 +112,7 @@ const char * errorMessage(Error code)
         case Error::ZSESSIONMOVED:            return "Session moved to another server, so operation is ignored";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 bool isHardwareError(Error zk_return_code)

src/Common/tests/gtest_thread_pool_schedule_exception.cpp

@@ -36,7 +36,7 @@ static bool check()
         return true;
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Compression/CompressionCodecDeflateQpl.cpp

@@ -393,7 +393,7 @@ void CompressionCodecDeflateQpl::doDecompressData(const char * source, UInt32 so
             sw_codec->doDecompressData(source, source_size, dest, uncompressed_size);
             return;
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void CompressionCodecDeflateQpl::flushAsynchronousDecompressRequests()

src/Compression/CompressionCodecDoubleDelta.cpp

@@ -164,7 +164,7 @@ inline Int64 getMaxValueForByteSize(Int8 byte_size)
         default:
             assert(false && "only 1, 2, 4 and 8 data sizes are supported");
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 struct WriteSpec

src/Core/AccurateComparison.h

@@ -67,7 +67,7 @@ bool lessOp(A a, B b)
 
     static_assert(is_integer<A> || std::is_floating_point_v<A>);
     static_assert(is_integer<B> || std::is_floating_point_v<B>);
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename A, typename B>

src/Core/Field.cpp

@@ -492,7 +492,7 @@ Field Field::restoreFromDump(std::string_view dump_)
     }
 
     show_error();
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Core/Field.h

@@ -604,7 +604,7 @@ public:
             case Types::AggregateFunctionState: return f(field.template get<AggregateFunctionStateData>());
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     String dump() const;

src/DataTypes/Serializations/ISerialization.cpp

@@ -36,7 +36,7 @@ String ISerialization::kindToString(Kind kind)
         case Kind::SPARSE:
             return "Sparse";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 ISerialization::Kind ISerialization::stringToKind(const String & str)

src/Databases/DatabaseReplicated.cpp

@@ -357,8 +357,7 @@ bool DatabaseReplicated::createDatabaseNodesInZooKeeper(const zkutil::ZooKeeperP
 
     /// Other codes are unexpected, will throw
     zkutil::KeeperMultiException::check(res, ops, responses);
-    chassert(false);
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 bool DatabaseReplicated::looksLikeReplicatedDatabasePath(const ZooKeeperPtr & current_zookeeper, const String & path)

src/Dictionaries/RedisDictionarySource.cpp

@@ -124,7 +124,7 @@ namespace DB
                 return "none";
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     QueryPipeline RedisDictionarySource::loadAll()

src/Disks/DiskType.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <base/defines.h>
 #include <base/types.h>
 
 namespace DB
@@ -32,7 +33,7 @@ inline String toString(DataSourceType data_source_type)
         case DataSourceType::AzureBlobStorage:
             return "azure_blob_storage";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 struct DataSourceDescription

src/Disks/IO/CachedOnDiskReadBufferFromFile.h

@@ -127,7 +127,7 @@ private:
             case ReadType::REMOTE_FS_READ_AND_PUT_IN_CACHE:
                 return "REMOTE_FS_READ_AND_PUT_IN_CACHE";
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     size_t first_offset = 0;

src/Disks/ObjectStorages/MetadataFromDiskTransactionState.cpp

@@ -1,3 +1,4 @@
+#include <base/defines.h>
 #include <Disks/ObjectStorages/MetadataFromDiskTransactionState.h>
 
 namespace DB
@@ -16,7 +17,7 @@ std::string toString(MetadataFromDiskTransactionState state)
         case MetadataFromDiskTransactionState::PARTIALLY_ROLLED_BACK:
             return "PARTIALLY_ROLLED_BACK";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 }

src/Disks/VolumeJBOD.cpp

@@ -97,7 +97,7 @@ DiskPtr VolumeJBOD::getDisk(size_t /* index */) const
             return disks_by_size.top().disk;
         }
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 ReservationPtr VolumeJBOD::reserve(UInt64 bytes)
@@ -137,7 +137,7 @@ ReservationPtr VolumeJBOD::reserve(UInt64 bytes)
             return reservation;
         }
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 bool VolumeJBOD::areMergesAvoided() const

src/Formats/EscapingRuleUtils.cpp

@@ -70,7 +70,7 @@ String escapingRuleToString(FormatSettings::EscapingRule escaping_rule)
         case FormatSettings::EscapingRule::Raw:
             return "Raw";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void skipFieldByEscapingRule(ReadBuffer & buf, FormatSettings::EscapingRule escaping_rule, const FormatSettings & format_settings)
@@ -99,7 +99,7 @@ void skipFieldByEscapingRule(ReadBuffer & buf, FormatSettings::EscapingRule esca
             readStringInto(out, buf);
             break;
         default:
-            __builtin_unreachable();
+            UNREACHABLE();
     }
 }
 

src/Formats/ProtobufSerializer.cpp

@@ -3535,7 +3535,7 @@ namespace
             }
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 

src/Functions/FunctionsConversion.h

@@ -2273,7 +2273,7 @@ struct ToNumberMonotonicity
             }
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 };
 

src/Functions/FunctionsRound.h

@@ -151,7 +151,7 @@ struct IntegerRoundingComputation
             }
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     static ALWAYS_INLINE T compute(T x, T scale)
@@ -165,7 +165,7 @@ struct IntegerRoundingComputation
                 return computeImpl(x, scale);
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     static ALWAYS_INLINE void compute(const T * __restrict in, size_t scale, T * __restrict out) requires std::integral<T>
@@ -249,7 +249,7 @@ inline float roundWithMode(float x, RoundingMode mode)
         case RoundingMode::Trunc: return truncf(x);
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 inline double roundWithMode(double x, RoundingMode mode)
@@ -262,7 +262,7 @@ inline double roundWithMode(double x, RoundingMode mode)
         case RoundingMode::Trunc: return trunc(x);
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename T>

src/Functions/FunctionsTimeWindow.cpp

@@ -194,7 +194,7 @@ struct TimeWindowImpl<TUMBLE>
             default:
                 throw Exception("Fraction seconds are unsupported by windows yet", ErrorCodes::SYNTAX_ERROR);
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     template <typename ToType, IntervalKind::Kind unit>
@@ -397,7 +397,7 @@ struct TimeWindowImpl<HOP>
             default:
                 throw Exception("Fraction seconds are unsupported by windows yet", ErrorCodes::SYNTAX_ERROR);
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     template <typename ToType, IntervalKind::Kind kind>
@@ -546,7 +546,7 @@ struct TimeWindowImpl<WINDOW_ID>
             default:
                 throw Exception("Fraction seconds are unsupported by windows yet", ErrorCodes::SYNTAX_ERROR);
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     template <typename ToType, IntervalKind::Kind kind>

src/Functions/PolygonUtils.h

@@ -384,7 +384,7 @@ bool PointInPolygonWithGrid<CoordinateType>::contains(CoordinateType x, Coordina
             return boost::geometry::within(Point(x, y), polygons[cell.index_of_inner_polygon]);
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Functions/toStartOfInterval.cpp

@@ -510,7 +510,7 @@ private:
                 return execute<FromDataType, DataTypeDate, IntervalKind::Year>(from, time_column, num_units, result_type, time_zone, scale);
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     template <typename FromDataType, typename ToDataType, IntervalKind::Kind unit, typename ColumnType>

src/IO/CompressionMethod.cpp

@@ -52,7 +52,7 @@ std::string toContentEncodingName(CompressionMethod method)
         case CompressionMethod::None:
             return "";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 CompressionMethod chooseHTTPCompressionMethod(const std::string & list)

src/IO/DoubleConverter.h

@@ -5,6 +5,7 @@
 #pragma clang diagnostic ignored "-Wdouble-promotion"
 #endif
 
+#include <base/defines.h>
 #include <double-conversion/double-conversion.h>
 #include <boost/noncopyable.hpp>
 

src/IO/HadoopSnappyReadBuffer.h

@@ -85,7 +85,7 @@ public:
             case Status::NEEDS_MORE_INPUT:
                 return "NEEDS_MORE_INPUT";
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     explicit HadoopSnappyReadBuffer(

src/Interpreters/Aggregator.cpp

@@ -206,7 +206,7 @@ DB::AggregatedDataVariants::Type convertToTwoLevelTypeIfPossible(DB::AggregatedD
         default:
             return type;
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void initDataVariantsWithSizeHint(

src/Interpreters/Aggregator.h

@@ -688,7 +688,7 @@ struct AggregatedDataVariants : private boost::noncopyable
         #undef M
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     /// The size without taking into account the row in which data is written for the calculation of TOTALS.
@@ -705,7 +705,7 @@ struct AggregatedDataVariants : private boost::noncopyable
             #undef M
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     const char * getMethodName() const
@@ -721,7 +721,7 @@ struct AggregatedDataVariants : private boost::noncopyable
         #undef M
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     bool isTwoLevel() const
@@ -737,7 +737,7 @@ struct AggregatedDataVariants : private boost::noncopyable
         #undef M
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     #define APPLY_FOR_VARIANTS_CONVERTIBLE_TO_TWO_LEVEL(M) \

src/Interpreters/Cache/FileSegment.cpp

@@ -653,7 +653,7 @@ String FileSegment::stateToString(FileSegment::State state)
         case FileSegment::State::SKIP_CACHE:
             return "SKIP_CACHE";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void FileSegment::assertCorrectness() const

src/Interpreters/ComparisonGraph.cpp

@@ -156,7 +156,7 @@ ComparisonGraph::CompareResult ComparisonGraph::pathToCompareResult(Path path, b
         case Path::GREATER: return inverse ? CompareResult::LESS : CompareResult::GREATER;
         case Path::GREATER_OR_EQUAL: return inverse ? CompareResult::LESS_OR_EQUAL : CompareResult::GREATER_OR_EQUAL;
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 std::optional<ComparisonGraph::Path> ComparisonGraph::findPath(size_t start, size_t finish) const

src/Interpreters/FilesystemCacheLog.cpp

@@ -23,7 +23,7 @@ static String typeToString(FilesystemCacheLogElement::CacheType type)
         case FilesystemCacheLogElement::CacheType::WRITE_THROUGH_CACHE:
             return "WRITE_THROUGH_CACHE";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 NamesAndTypesList FilesystemCacheLogElement::getNamesAndTypes()

src/Interpreters/HashJoin.cpp

@@ -624,7 +624,7 @@ namespace
             APPLY_FOR_JOIN_VARIANTS(M)
         #undef M
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 
@@ -1852,7 +1852,7 @@ private:
                 throw Exception(ErrorCodes::UNSUPPORTED_JOIN_KEYS, "Unsupported JOIN keys (type: {})", parent.data->type)   ;
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     template <JoinStrictness STRICTNESS, typename Map>

src/Interpreters/HashJoin.h

@@ -279,7 +279,7 @@ public:
             #undef M
             }
 
-            __builtin_unreachable();
+            UNREACHABLE();
         }
 
         size_t getTotalByteCountImpl(Type which) const
@@ -295,7 +295,7 @@ public:
             #undef M
             }
 
-            __builtin_unreachable();
+            UNREACHABLE();
         }
 
         size_t getBufferSizeInCells(Type which) const
@@ -311,7 +311,7 @@ public:
             #undef M
             }
 
-            __builtin_unreachable();
+            UNREACHABLE();
         }
     };
 

src/Interpreters/InterpreterTransactionControlQuery.cpp

@@ -32,8 +32,7 @@ BlockIO InterpreterTransactionControlQuery::execute()
         case ASTTransactionControl::SET_SNAPSHOT:
             return executeSetSnapshot(session_context, tcl.snapshot);
     }
-    assert(false);
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 BlockIO InterpreterTransactionControlQuery::executeBegin(ContextMutablePtr session_context)

src/Interpreters/RowRefs.cpp

@@ -37,7 +37,7 @@ void callWithType(TypeIndex type, F && f)
     DISPATCH(DateTime64)
 #undef DISPATCH
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename TKey, ASOFJoinInequality inequality>

src/Interpreters/SetVariants.cpp

@@ -42,7 +42,7 @@ size_t SetVariantsTemplate<Variant>::getTotalRowCount() const
     #undef M
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename Variant>
@@ -58,7 +58,7 @@ size_t SetVariantsTemplate<Variant>::getTotalByteCount() const
     #undef M
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 template <typename Variant>

src/Parsers/ASTAlterQuery.cpp

@@ -124,7 +124,7 @@ const char * ASTAlterCommand::typeToString(ASTAlterCommand::Type type)
         case MODIFY_DATABASE_SETTING: return "MODIFY_DATABASE_SETTING";
         case MODIFY_COMMENT: return "MODIFY_COMMENT";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void ASTAlterCommand::formatImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const

src/Parsers/ASTExplainQuery.h

@@ -116,7 +116,7 @@ private:
             case CurrentTransaction: return "EXPLAIN CURRENT TRANSACTION";
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 };
 

src/Parsers/Lexer.cpp

@@ -1,3 +1,4 @@
+#include <base/defines.h>
 #include <Parsers/Lexer.h>
 #include <Common/StringUtils/StringUtils.h>
 #include <base/find_symbols.h>
@@ -39,7 +40,7 @@ Token quotedString(const char *& pos, const char * const token_begin, const char
             continue;
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 }
 
@@ -414,7 +415,7 @@ APPLY_FOR_TOKENS(M)
 #undef M
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Processors/Formats/Impl/MsgPackRowInputFormat.cpp

@@ -512,7 +512,7 @@ DataTypePtr MsgPackSchemaReader::getDataType(const msgpack::object & object)
             throw Exception(ErrorCodes::BAD_ARGUMENTS, "Msgpack extension type {:x} is not supported", object_ext.type());
         }
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 DataTypes MsgPackSchemaReader::readRowAndGetDataTypes()

src/Processors/IProcessor.cpp

@@ -37,7 +37,7 @@ std::string IProcessor::statusToName(Status status)
             return "ExpandPipeline";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 }

src/Processors/QueryPlan/ReadFromMergeTree.cpp

@@ -639,7 +639,7 @@ static void addMergingFinal(
                             sort_description, max_block_size, merging_params.graphite_params, now);
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     };
 
     pipe.addTransform(get_merging_processor());
@@ -1240,7 +1240,7 @@ static const char * indexTypeToString(ReadFromMergeTree::IndexType type)
             return "Skip";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 static const char * readTypeToString(ReadFromMergeTree::ReadType type)
@@ -1255,7 +1255,7 @@ static const char * readTypeToString(ReadFromMergeTree::ReadType type)
             return "InReverseOrder";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void ReadFromMergeTree::describeActions(FormatSettings & format_settings) const

src/Processors/QueryPlan/TotalsHavingStep.cpp

@@ -88,7 +88,7 @@ static String totalsModeToString(TotalsMode totals_mode, double auto_include_thr
             return "after_having_auto threshold " + std::to_string(auto_include_threshold);
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void TotalsHavingStep::describeActions(FormatSettings & settings) const

src/Processors/Transforms/FillingTransform.cpp

@@ -45,7 +45,7 @@ static FillColumnDescription::StepFunction getStepFunction(
         FOR_EACH_INTERVAL_KIND(DECLARE_CASE)
 #undef DECLARE_CASE
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 static bool tryConvertFields(FillColumnDescription & descr, const DataTypePtr & type)

src/Processors/Transforms/buildPushingToViewsChain.cpp

@@ -744,7 +744,7 @@ static std::exception_ptr addStorageToException(std::exception_ptr ptr, const St
         return std::current_exception();
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void FinalizingViewsTransform::work()

src/Server/GRPCServer.cpp

@@ -390,7 +390,7 @@ namespace
             case CALL_WITH_STREAM_IO: return "ExecuteQueryWithStreamIO()";
             case CALL_MAX: break;
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     bool isInputStreaming(CallType call_type)
@@ -550,7 +550,7 @@ namespace
             case CALL_WITH_STREAM_IO: return std::make_unique<Responder<CALL_WITH_STREAM_IO>>();
             case CALL_MAX: break;
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
 

src/Server/HTTPHandler.cpp

@@ -878,8 +878,7 @@ try
     }
     else
     {
-        assert(false);
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     used_output.finalize();

src/Storages/ColumnsDescription.cpp

@@ -490,7 +490,7 @@ static GetColumnsOptions::Kind defaultKindToGetKind(ColumnDefaultKind kind)
         case ColumnDefaultKind::Ephemeral:
             return GetColumnsOptions::Ephemeral;
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 NamesAndTypesList ColumnsDescription::getByNames(const GetColumnsOptions & options, const Names & names) const

src/Storages/MergeTree/BackgroundJobsAssignee.cpp

@@ -90,7 +90,7 @@ String BackgroundJobsAssignee::toString(Type type)
         case Type::Moving:
             return "Moving";
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void BackgroundJobsAssignee::start()

src/Storages/MergeTree/KeyCondition.cpp

@@ -2581,7 +2581,7 @@ String KeyCondition::RPNElement::toString(std::string_view column_name, bool pri
             return "true";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Storages/MergeTree/MergeTreeData.cpp

@@ -928,7 +928,7 @@ String MergeTreeData::MergingParams::getModeName() const
         case VersionedCollapsing: return "VersionedCollapsing";
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 Int64 MergeTreeData::getMaxBlockNumber() const

src/Storages/MergeTree/MergeTreeDataWriter.cpp

@@ -244,7 +244,7 @@ Block MergeTreeDataWriter::mergeBlock(
                     block, 1, sort_description, block_size + 1, merging_params.graphite_params, time(nullptr));
         }
 
-        __builtin_unreachable();
+        UNREACHABLE();
     };
 
     auto merging_algorithm = get_merging_algorithm();

src/Storages/MergeTree/ParallelReplicasReadingCoordinator.cpp

@@ -125,7 +125,7 @@ PartitionReadResponse ParallelReplicasReadingCoordinator::Impl::handleRequest(Pa
         }
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 PartitionReadResponse ParallelReplicasReadingCoordinator::handleRequest(PartitionReadRequest request)

src/Storages/MergeTree/PartMovesBetweenShardsOrchestrator.cpp

@@ -609,7 +609,7 @@ PartMovesBetweenShardsOrchestrator::Entry PartMovesBetweenShardsOrchestrator::st
         }
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void PartMovesBetweenShardsOrchestrator::removePins(const Entry & entry, zkutil::ZooKeeperPtr zk)

src/Storages/MergeTree/ReplicatedMergeTreeRestartingThread.cpp

@@ -123,7 +123,7 @@ bool ReplicatedMergeTreeRestartingThread::runImpl()
     }
     else
     {
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     try

src/Storages/StorageDistributed.cpp

@@ -1422,7 +1422,7 @@ size_t StorageDistributed::getRandomShardIndex(const Cluster::ShardsInfo & shard
         res -= shards[i].weight;
     }
 
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 

src/Storages/WindowView/StorageWindowView.cpp

@@ -296,7 +296,7 @@ namespace
             CASE_WINDOW_KIND(Year)
 #undef CASE_WINDOW_KIND
         }
-        __builtin_unreachable();
+        UNREACHABLE();
     }
 
     class AddingAggregatedChunkInfoTransform : public ISimpleTransform
@@ -895,7 +895,7 @@ UInt32 StorageWindowView::getWindowLowerBound(UInt32 time_sec)
         CASE_WINDOW_KIND(Year)
 #undef CASE_WINDOW_KIND
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 UInt32 StorageWindowView::getWindowUpperBound(UInt32 time_sec)
@@ -923,7 +923,7 @@ UInt32 StorageWindowView::getWindowUpperBound(UInt32 time_sec)
         CASE_WINDOW_KIND(Year)
 #undef CASE_WINDOW_KIND
     }
-    __builtin_unreachable();
+    UNREACHABLE();
 }
 
 void StorageWindowView::addFireSignal(std::set<UInt32> & signals)

utils/check-style/check-style

@@ -352,3 +352,8 @@ find $ROOT_PATH | sort -f | uniq -i -c | awk '{ if ($1 > 1) print }'
 find $ROOT_PATH/{src,programs,utils} -name '*.h' -or -name '*.cpp' |
     grep -vP $EXCLUDE_DIRS |
     xargs grep -P '::(is|read)_symlink' | grep -v "STYLE_CHECK_ALLOW_STD_FS_SYMLINK" && echo "Use DB::FS::isSymlink and DB::FS::readSymlink instead"
+
+# Forbid __builtin_unreachable(), because it's hard to debug when it becomes reachable
+find $ROOT_PATH/{src,programs,utils} -name '*.h' -or -name '*.cpp' |
+    grep -vP $EXCLUDE_DIRS |
+    xargs grep -P '__builtin_unreachable' && echo "Use UNREACHABLE() from defines.h instead"