diff --git a/contrib/aws-cmake/AwsThreadAffinity.cmake b/contrib/aws-cmake/AwsThreadAffinity.cmake
index 9e53481272c..7f30fb71b43 100644
--- a/contrib/aws-cmake/AwsThreadAffinity.cmake
+++ b/contrib/aws-cmake/AwsThreadAffinity.cmake
@@ -1,50 +1,9 @@
 # Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 # SPDX-License-Identifier: Apache-2.0.
 
-include(CheckSymbolExists)
-
 # Check if the platform supports setting thread affinity
 # (important for hitting full NIC entitlement on NUMA architectures)
 function(aws_set_thread_affinity_method target)
-
-    # Non-POSIX, Android, and Apple platforms do not support thread affinity.
-    if (NOT UNIX OR ANDROID OR APPLE)
-        target_compile_definitions(${target} PRIVATE
-            -DAWS_AFFINITY_METHOD=AWS_AFFINITY_METHOD_NONE)
-        return()
-    endif()
-
-    cmake_push_check_state()
-    list(APPEND CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
-    list(APPEND CMAKE_REQUIRED_LIBRARIES pthread)
-
-    set(headers "pthread.h")
-    # BSDs put nonportable pthread declarations in a separate header.
-    if(CMAKE_SYSTEM_NAME MATCHES BSD)
-        set(headers "${headers};pthread_np.h")
-    endif()
-
-    # Using pthread attrs is the preferred method, but is glibc-specific.
-    check_symbol_exists(pthread_attr_setaffinity_np "${headers}" USE_PTHREAD_ATTR_SETAFFINITY)
-    if (USE_PTHREAD_ATTR_SETAFFINITY)
-        target_compile_definitions(${target} PRIVATE
-            -DAWS_AFFINITY_METHOD=AWS_AFFINITY_METHOD_PTHREAD_ATTR)
-        return()
-    endif()
-
-    # This method is still nonportable, but is supported by musl and BSDs.
-    check_symbol_exists(pthread_setaffinity_np "${headers}" USE_PTHREAD_SETAFFINITY)
-    if (USE_PTHREAD_SETAFFINITY)
-        target_compile_definitions(${target} PRIVATE
-            -DAWS_AFFINITY_METHOD=AWS_AFFINITY_METHOD_PTHREAD)
-        return()
-    endif()
-
-    # If we got here, we expected thread affinity support but didn't find it.
-    # We still build with degraded NUMA performance, but show a warning.
-    message(WARNING "No supported method for setting thread affinity")
-    target_compile_definitions(${target} PRIVATE
-        -DAWS_AFFINITY_METHOD=AWS_AFFINITY_METHOD_NONE)
-
-    cmake_pop_check_state()
+    # This code has been cut, because I don't care about it.
+    target_compile_definitions(${target} PRIVATE -DAWS_AFFINITY_METHOD=AWS_AFFINITY_METHOD_NONE)
 endfunction()
diff --git a/contrib/aws-cmake/AwsThreadName.cmake b/contrib/aws-cmake/AwsThreadName.cmake
index a67416b4f83..e17759435ed 100644
--- a/contrib/aws-cmake/AwsThreadName.cmake
+++ b/contrib/aws-cmake/AwsThreadName.cmake
@@ -1,61 +1,13 @@
 # Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 # SPDX-License-Identifier: Apache-2.0.
 
-include(CheckSymbolExists)
-
 # Check how the platform supports setting thread name
 function(aws_set_thread_name_method target)
-
-    if (WINDOWS)
-        # On Windows we do a runtime check, instead of compile-time check
-        return()
-    elseif (APPLE)
+    if (APPLE)
         # All Apple platforms we support have the same function, so no need for compile-time check.
         return()
     endif()
 
-    cmake_push_check_state()
-    list(APPEND CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
-    list(APPEND CMAKE_REQUIRED_LIBRARIES pthread)
-
-    # The start of the test program
-    set(c_source_start "
-        #define _GNU_SOURCE
-        #include <pthread.h>
-
-        #if defined(__FreeBSD__) || defined(__NETBSD__)
-        #include <pthread_np.h>
-        #endif
-
-        int main() {
-            pthread_t thread_id;
-        ")
-
-    # The end of the test program
-    set(c_source_end "}")
-
     # pthread_setname_np() usually takes 2 args
-    check_c_source_compiles("
-        ${c_source_start}
-        pthread_setname_np(thread_id, \"asdf\");
-        ${c_source_end}"
-        PTHREAD_SETNAME_TAKES_2ARGS)
-    if (PTHREAD_SETNAME_TAKES_2ARGS)
-        target_compile_definitions(${target} PRIVATE -DAWS_PTHREAD_SETNAME_TAKES_2ARGS)
-        return()
-    endif()
-
-    # But on NetBSD it takes 3!
-    check_c_source_compiles("
-        ${c_source_start}
-        pthread_setname_np(thread_id, \"asdf\", NULL);
-        ${c_source_end}
-        " PTHREAD_SETNAME_TAKES_3ARGS)
-    if (PTHREAD_SETNAME_TAKES_3ARGS)
-        target_compile_definitions(${target} PRIVATE -DAWS_PTHREAD_SETNAME_TAKES_3ARGS)
-        return()
-    endif()
-
-    # And on many older/weirder platforms it's just not supported
-    cmake_pop_check_state()
+    target_compile_definitions(${target} PRIVATE -DAWS_PTHREAD_SETNAME_TAKES_2ARGS)
 endfunction()
diff --git a/contrib/libcxx-cmake/CMakeLists.txt b/contrib/libcxx-cmake/CMakeLists.txt
index b7e59e2c9a3..c77d5d8319e 100644
--- a/contrib/libcxx-cmake/CMakeLists.txt
+++ b/contrib/libcxx-cmake/CMakeLists.txt
@@ -1,5 +1,3 @@
-include(CheckCXXCompilerFlag)
-
 set(LIBCXX_SOURCE_DIR "${ClickHouse_SOURCE_DIR}/contrib/llvm-project/libcxx")
 
 set(SRCS
diff --git a/contrib/rocksdb-cmake/CMakeLists.txt b/contrib/rocksdb-cmake/CMakeLists.txt
index 466adf6aff0..2b6c48f0b38 100644
--- a/contrib/rocksdb-cmake/CMakeLists.txt
+++ b/contrib/rocksdb-cmake/CMakeLists.txt
@@ -76,7 +76,6 @@ else()
   endif()
 endif()
 
-include(CheckCCompilerFlag)
 if(CMAKE_SYSTEM_PROCESSOR MATCHES "^(powerpc|ppc)64")
   if(POWER9)
     set(HAS_POWER9 1)
@@ -88,21 +87,12 @@ if(CMAKE_SYSTEM_PROCESSOR MATCHES "^(powerpc|ppc)64")
 endif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(powerpc|ppc)64")
 
 if(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64|arm64|ARM64")
-  CHECK_C_COMPILER_FLAG("-march=armv8-a+crc+crypto" HAS_ARMV8_CRC)
-  if(HAS_ARMV8_CRC)
-    message(STATUS " HAS_ARMV8_CRC yes")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv8-a+crc+crypto -Wno-unused-function")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=armv8-a+crc+crypto -Wno-unused-function")
-  endif(HAS_ARMV8_CRC)
+  set(HAS_ARMV8_CRC 1)
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv8-a+crc+crypto -Wno-unused-function")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=armv8-a+crc+crypto -Wno-unused-function")
 endif(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64|arm64|ARM64")
 
 
-include(CheckCXXSourceCompiles)
-if(NOT MSVC)
-  set(CMAKE_REQUIRED_FLAGS "-msse4.2 -mpclmul")
-endif()
-
-unset(CMAKE_REQUIRED_FLAGS)
 if(HAVE_SSE42)
   add_definitions(-DHAVE_SSE42)
   add_definitions(-DHAVE_PCLMUL)
@@ -121,75 +111,18 @@ elseif(CMAKE_SYSTEM_NAME MATCHES "Linux")
   add_definitions(-DOS_LINUX)
 elseif(CMAKE_SYSTEM_NAME MATCHES "SunOS")
   add_definitions(-DOS_SOLARIS)
-elseif(CMAKE_SYSTEM_NAME MATCHES "kFreeBSD")
-  add_definitions(-DOS_GNU_KFREEBSD)
 elseif(CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
   add_definitions(-DOS_FREEBSD)
-elseif(CMAKE_SYSTEM_NAME MATCHES "NetBSD")
-  add_definitions(-DOS_NETBSD)
-elseif(CMAKE_SYSTEM_NAME MATCHES "OpenBSD")
-  add_definitions(-DOS_OPENBSD)
-elseif(CMAKE_SYSTEM_NAME MATCHES "DragonFly")
-  add_definitions(-DOS_DRAGONFLYBSD)
 elseif(CMAKE_SYSTEM_NAME MATCHES "Android")
   add_definitions(-DOS_ANDROID)
-elseif(CMAKE_SYSTEM_NAME MATCHES "Windows")
-  add_definitions(-DWIN32 -DOS_WIN -D_MBCS -DWIN64 -DNOMINMAX)
-  if(MINGW)
-    add_definitions(-D_WIN32_WINNT=_WIN32_WINNT_VISTA)
-  endif()
 endif()
 
-if(NOT WIN32)
-  add_definitions(-DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX)
-endif()
+add_definitions(-DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX)
 
-option(WITH_FALLOCATE "build with fallocate" ON)
-if(WITH_FALLOCATE)
-  CHECK_C_SOURCE_COMPILES("
-#include <fcntl.h>
-#include <linux/falloc.h>
-int main() {
- int fd = open(\"/dev/null\", 0);
- fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 1024);
-}
-" HAVE_FALLOCATE)
-  if(HAVE_FALLOCATE)
-    add_definitions(-DROCKSDB_FALLOCATE_PRESENT)
-  endif()
-endif()
-
-CHECK_C_SOURCE_COMPILES("
-#include <fcntl.h>
-int main() {
-  int fd = open(\"/dev/null\", 0);
-  sync_file_range(fd, 0, 1024, SYNC_FILE_RANGE_WRITE);
-}
-" HAVE_SYNC_FILE_RANGE_WRITE)
-if(HAVE_SYNC_FILE_RANGE_WRITE)
-  add_definitions(-DROCKSDB_RANGESYNC_PRESENT)
-endif()
-
-CHECK_C_SOURCE_COMPILES("
-#include <pthread.h>
-int main() {
-  (void) PTHREAD_MUTEX_ADAPTIVE_NP;
-}
-" HAVE_PTHREAD_MUTEX_ADAPTIVE_NP)
-if(HAVE_PTHREAD_MUTEX_ADAPTIVE_NP)
+if (OS_LINUX OR OS_FREEBSD)
   add_definitions(-DROCKSDB_PTHREAD_ADAPTIVE_MUTEX)
 endif()
 
-include(CheckCXXSymbolExists)
-if (OS_FREEBSD)
-  check_cxx_symbol_exists(malloc_usable_size "${ROCKSDB_SOURCE_DIR}/malloc_np.h" HAVE_MALLOC_USABLE_SIZE)
-else()
-  check_cxx_symbol_exists(malloc_usable_size "${ROCKSDB_SOURCE_DIR}/malloc.h" HAVE_MALLOC_USABLE_SIZE)
-endif()
-if(HAVE_MALLOC_USABLE_SIZE)
-  add_definitions(-DROCKSDB_MALLOC_USABLE_SIZE)
-endif()
-
 if (OS_LINUX)
   add_definitions(-DROCKSDB_SCHED_GETCPU_PRESENT)
   add_definitions(-DROCKSDB_AUXV_SYSAUXV_PRESENT)
@@ -204,7 +137,6 @@ include_directories("${ROCKSDB_SOURCE_DIR}/include")
 if(WITH_FOLLY_DISTRIBUTED_MUTEX)
   include_directories("${ROCKSDB_SOURCE_DIR}/third-party/folly")
 endif()
-find_package(Threads REQUIRED)
 
 # Main library source code
 
@@ -497,7 +429,7 @@ set(SOURCES
     ${ROCKSDB_SOURCE_DIR}/utilities/transactions/lock/range/range_tree/lib/util/memarena.cc
     rocksdb_build_version.cc)
 
-if(HAVE_SSE42 AND NOT MSVC)
+if(HAVE_SSE42)
   set_source_files_properties(
     "${ROCKSDB_SOURCE_DIR}/util/crc32c.cc"
     PROPERTIES COMPILE_FLAGS "-msse4.2 -mpclmul")
diff --git a/contrib/xz-cmake/CMakeLists.txt b/contrib/xz-cmake/CMakeLists.txt
index c3a8203c83e..c73433d9863 100644
--- a/contrib/xz-cmake/CMakeLists.txt
+++ b/contrib/xz-cmake/CMakeLists.txt
@@ -98,8 +98,6 @@ if (ARCH_S390X)
     add_compile_definitions(WORDS_BIGENDIAN)
 endif ()
 
-find_package(Threads REQUIRED)
-
 
 add_library(_liblzma
     ${SRC_DIR}/src/common/mythread.h
diff --git a/utils/check-style/check-style b/utils/check-style/check-style
index f87d2e292b5..bd6f111354e 100755
--- a/utils/check-style/check-style
+++ b/utils/check-style/check-style
@@ -422,3 +422,6 @@ find $ROOT_PATH/{src,programs,utils} -name '*.h' -or -name '*.cpp' | xargs grep
 
 # Cyrillic characters hiding inside Latin.
 find $ROOT_PATH/{src,programs,utils} -name '*.h' -or -name '*.cpp' | xargs grep -P --line-number '[a-zA-Z][а-яА-ЯёЁ]|[а-яА-ЯёЁ][a-zA-Z]' && echo "^ Cyrillic characters found in unexpected place."
+
+# Don't allow dynamic compiler check with CMake, because we are using hermetic, reproducible, cross-compiled, static (TLDR, good) builds.
+ls -1d $ROOT_PATH/contrib/*-cmake | xargs -I@ find @ -name 'CMakeLists.txt' -or -name '*.cmake' | xargs grep --with-filename -i -P 'check_c_compiler_flag|check_cxx_compiler_flag|check_c_source_compiles|check_cxx_source_compiles|check_include_file|check_symbol_exists|cmake_push_check_state|cmake_pop_check_state|find_package|CMAKE_REQUIRED_FLAGS|CheckIncludeFile|CheckCCompilerFlag|CheckCXXCompilerFlag|CheckCSourceCompiles|CheckCXXSourceCompiles|CheckCSymbolExists|CheckCXXSymbolExists' | grep -v Rust && echo "^ It's not allowed to have dynamic compiler checks with CMake."