diff --git a/Tools/build/.warningignore_macos b/Tools/build/.warningignore_macos
index 2ed02ba6b63..e9307b44c7e 100644
--- a/Tools/build/.warningignore_macos
+++ b/Tools/build/.warningignore_macos
@@ -3,226 +3,7 @@
 # Keep lines sorted lexicographically to help avoid merge conflicts.
 # Format example:
 # /path/to/file (number of warnings in file)
-Include/internal/mimalloc/mimalloc/internal.h 4
-Include/internal/pycore_backoff.h 1
-Include/internal/pycore_dict.h 2
-Modules/_asynciomodule.c 3
-Modules/_bisectmodule.c 2
-Modules/_bz2module.c 5
-Modules/_collectionsmodule.c 2
-Modules/_csv.c 3
-Modules/_ctypes/_ctypes.c 37
-Modules/_ctypes/_ctypes_test_generated.c.h 141
-Modules/_ctypes/callbacks.c 6
-Modules/_ctypes/callproc.c 15
-Modules/_ctypes/cfield.c 56
-Modules/_ctypes/malloc_closure.c 3
-Modules/_ctypes/stgdict.c 17
-Modules/_cursesmodule.c 24
-Modules/_datetimemodule.c 28
-Modules/_dbmmodule.c 8
-Modules/_decimal/_decimal.c 15
-Modules/_elementtree.c 42
-Modules/_functoolsmodule.c 6
-Modules/_gdbmmodule.c 5
-Modules/_hacl/Hacl_Hash_Blake2b_Simd256.c 84
-Modules/_hacl/Hacl_Hash_Blake2s_Simd128.c 84
-Modules/_hacl/include/krml/FStar_UInt_8_16_32_64.h 24
-Modules/_hashopenssl.c 16
-Modules/_interpchannelsmodule.c 1
-Modules/_interpqueuesmodule.c 1
-Modules/_io/_iomodule.c 1
-Modules/_io/bufferedio.c 4
-Modules/_io/bytesio.c 11
-Modules/_io/fileio.c 9
-Modules/_io/stringio.c 8
-Modules/_io/textio.c 11
-Modules/_json.c 19
-Modules/_localemodule.c 3
-Modules/_lzmamodule.c 10
-Modules/_multiprocessing/semaphore.c 2
-Modules/_operator.c 5
-Modules/_pickle.c 71
-Modules/_posixsubprocess.c 8
-Modules/_queuemodule.c 4
-Modules/_randommodule.c 3
-Modules/_scproxy.c 3
-Modules/_sqlite/connection.c 4
-Modules/_sqlite/cursor.c 3
-Modules/_sqlite/module.c 2
-Modules/_sre/sre.c 18
-Modules/_sre/sre_lib.h 62
-Modules/_ssl.c 29
-Modules/_struct.c 1
-Modules/_testbuffer.c 22
-Modules/_testcapi/heaptype.c 1
-Modules/_testcapi/long.c 2
-Modules/_testcapi/mem.c 2
-Modules/_testcapi/monitoring.c 3
-Modules/_testcapi/pyatomic.c 1
-Modules/_testcapi/unicode.c 2
-Modules/_testcapi/vectorcall.c 3
-Modules/_testcapi/watchers.c 3
-Modules/_testcapimodule.c 3
-Modules/_testclinic.c 14
-Modules/_testexternalinspection.c 7
-Modules/_testinternalcapi.c 8
-Modules/_testinternalcapi/pytime.c 8
-Modules/_testinternalcapi/test_critical_sections.c 1
-Modules/_testinternalcapi/test_lock.c 2
-Modules/_testlimitedcapi/heaptype_relative.c 4
-Modules/_testlimitedcapi/object.c 2
-Modules/_testlimitedcapi/unicode.c 2
-Modules/_threadmodule.c 2
-Modules/_tkinter.c 6
-Modules/_xxtestfuzz/_xxtestfuzz.c 1
-Modules/_xxtestfuzz/fuzzer.c 11
-Modules/_zoneinfo.c 14
-Modules/arraymodule.c 32
-Modules/atexitmodule.c 1
-Modules/binascii.c 206
-Modules/blake2module.c 6
-Modules/cjkcodecs/_codecs_cn.c 1
-Modules/cjkcodecs/_codecs_iso2022.c 2
-Modules/cjkcodecs/_codecs_jp.c 14
-Modules/cjkcodecs/_codecs_kr.c 3
-Modules/cjkcodecs/cjkcodecs.h 1
-Modules/cjkcodecs/multibytecodec.c 2
-Modules/clinic/_testclinic.c.h 1
-Modules/clinic/arraymodule.c.h 1
-Modules/clinic/unicodedata.c.h 10
-Modules/cmathmodule.c 1
-Modules/expat/siphash.h 8
-Modules/expat/xmlparse.c 45
-Modules/expat/xmltok.c 17
-Modules/expat/xmltok_impl.c 34
-Modules/faulthandler.c 3
-Modules/fcntlmodule.c 1
-Modules/getpath.c 7
-Modules/grpmodule.c 4
-Modules/itertoolsmodule.c 7
-Modules/main.c 2
-Modules/mathmodule.c 15
-Modules/mmapmodule.c 20
-Modules/posixmodule.c 67
-Modules/pwdmodule.c 4
-Modules/pyexpat.c 20
-Modules/readline.c 1
-Modules/resource.c 3
-Modules/rotatingtree.c 1
-Modules/selectmodule.c 6
-Modules/sha3module.c 4
-Modules/signalmodule.c 1
-Modules/socketmodule.c 44
-Modules/syslogmodule.c 3
-Modules/timemodule.c 4
-Modules/unicodedata.c 28
-Modules/unicodedata_db.h 1
-Modules/xxsubtype.c 2
-Modules/zlibmodule.c 16
-Objects/abstract.c 2
-Objects/bytearrayobject.c 34
-Objects/bytes_methods.c 9
-Objects/bytesobject.c 35
-Objects/call.c 13
-Objects/classobject.c 4
-Objects/codeobject.c 15
-Objects/descrobject.c 2
-Objects/dictobject.c 28
-Objects/fileobject.c 3
-Objects/floatobject.c 30
-Objects/frameobject.c 19
-Objects/funcobject.c 1
-Objects/genobject.c 5
-Objects/listobject.c 43
-Objects/longobject.c 46
-Objects/memoryobject.c 6
-Objects/methodobject.c 1
-Objects/mimalloc/alloc.c 6
-Objects/mimalloc/arena.c 6
-Objects/mimalloc/heap.c 1
-Objects/mimalloc/init.c 2
-Objects/mimalloc/options.c 1
-Objects/mimalloc/os.c 4
-Objects/mimalloc/page-queue.c 2
-Objects/mimalloc/page.c 1
-Objects/mimalloc/prim/osx/../unix/prim.c 2
-Objects/mimalloc/random.c 1
-Objects/mimalloc/segment.c 11
-Objects/mimalloc/stats.c 1
-Objects/moduleobject.c 2
-Objects/object.c 1
-Objects/obmalloc.c 6
-Objects/odictobject.c 3
-Objects/rangeobject.c 10
-Objects/setobject.c 13
-Objects/sliceobject.c 4
-Objects/stringlib/codecs.h 26
-Objects/stringlib/eq.h 1
-Objects/stringlib/fastsearch.h 14
-Objects/stringlib/join.h 1
-Objects/stringlib/replace.h 4
-Objects/stringlib/repr.h 21
-Objects/stringlib/transmogrify.h 5
-Objects/structseq.c 14
-Objects/tupleobject.c 10
-Objects/typeobject.c 17
-Objects/unicodectype.c 7
-Objects/unicodeobject.c 113
-Parser/action_helpers.c 4
-Parser/lexer/buffer.c 1
-Parser/lexer/lexer.c 12
-Parser/parser.c 116
-Parser/string_parser.c 7
-Parser/tokenizer/file_tokenizer.c 8
-Parser/tokenizer/helpers.c 7
-Parser/tokenizer/readline_tokenizer.c 3
-Programs/_freeze_module.c 1
-Python/Python-ast.c 15
-Python/asdl.c 3
-Python/assemble.c 7
-Python/ast_opt.c 7
-Python/bltinmodule.c 9
-Python/bootstrap_hash.c 4
-Python/ceval.c 8
-Python/ceval_gil.c 2
-Python/codecs.c 32
-Python/codegen.c 6
-Python/compile.c 2
-Python/context.c 1
-Python/crossinterp.c 2
-Python/crossinterp_data_lookup.h 1
-Python/dtoa.c 34
-Python/errors.c 1
-Python/fileutils.c 7
-Python/flowgraph.c 8
-Python/formatter_unicode.c 7
-Python/frame.c 4
-Python/gc.c 7
-Python/generated_cases.c.h 35
-Python/getargs.c 11
-Python/import.c 5
-Python/initconfig.c 11
-Python/instrumentation.c 31
-Python/intrinsics.c 1
-Python/legacy_tracing.c 3
-Python/lock.c 4
-Python/marshal.c 11
-Python/modsupport.c 3
-Python/mystrtoul.c 4
-Python/pathconfig.c 1
-Python/preconfig.c 2
-Python/pyarena.c 1
-Python/pyhash.c 2
-Python/pylifecycle.c 7
-Python/pystate.c 6
-Python/pystrhex.c 19
-Python/pystrtod.c 3
-Python/qsbr.c 2
-Python/specialize.c 10
-Python/suggestions.c 12
-Python/symtable.c 18
-Python/sysmodule.c 2
-Python/thread_pthread.h 1
-Python/traceback.c 6
-Python/tracemalloc.c 6
+Modules/expat/siphash.h 7
+Modules/expat/xmlparse.c 8
+Modules/expat/xmltok.c 3
+Modules/expat/xmltok_impl.c 26
\ No newline at end of file
diff --git a/Tools/build/.warningignore_ubuntu b/Tools/build/.warningignore_ubuntu
index d010152a229..980785d59ae 100644
--- a/Tools/build/.warningignore_ubuntu
+++ b/Tools/build/.warningignore_ubuntu
@@ -3,254 +3,4 @@
 # Keep lines sorted lexicographically to help avoid merge conflicts.
 # Format example:
 # /path/to/file (number of warnings in file)
-/home/runner/work/cpython/cpython/multissl/openssl/3.0.15/include/openssl/evp.h 2
-/home/runner/work/cpython/cpython/multissl/openssl/3.0.15/include/openssl/ssl.h 4
-/usr/include/tcl8.6/tclTomMathDecls.h 1
-Include/cpython/bytearrayobject.h 1
-Include/cpython/bytesobject.h 3
-Include/cpython/dictobject.h 2
-Include/cpython/listobject.h 1
-Include/cpython/pyctype.h 2
-Include/cpython/tupleobject.h 1
-Include/cpython/unicodeobject.h 7
-Include/internal/mimalloc/mimalloc/internal.h 4
-Include/internal/mimalloc/mimalloc/types.h 2
-Include/internal/pycore_asdl.h 1
-Include/internal/pycore_backoff.h 3
-Include/internal/pycore_blocks_output_buffer.h 1
-Include/internal/pycore_dict.h 2
-Include/internal/pycore_interp.h 1
-Include/internal/pycore_obmalloc.h 1
-Include/internal/pycore_pymath.h 1
-Include/internal/pycore_runtime_init.h 1
-Include/longobject.h 1
-Include/object.h 4
-Include/opcode_ids.h 1
-Include/pymacro.h 4
-Include/pymath.h 1
-Include/pymem.h 2
-Include/pyport.h 2
-Modules/_asynciomodule.c 3
-Modules/_bisectmodule.c 4
-Modules/_bz2module.c 5
-Modules/_collectionsmodule.c 2
-Modules/_csv.c 2
-Modules/_ctypes/_ctypes.c 53
-Modules/_ctypes/_ctypes_test.c 7
-Modules/_ctypes/_ctypes_test_generated.c.h 2
-Modules/_ctypes/callbacks.c 3
-Modules/_ctypes/callproc.c 13
-Modules/_ctypes/cfield.c 33
-Modules/_ctypes/stgdict.c 17
-Modules/_cursesmodule.c 27
-Modules/_datetimemodule.c 38
-Modules/_datetimemodule.c 38
-Modules/_dbmmodule.c 7
-Modules/_decimal/_decimal.c 19
-Modules/_elementtree.c 37
-Modules/_functoolsmodule.c 6
-Modules/_gdbmmodule.c 4
-Modules/_hacl/Hacl_Hash_Blake2b_Simd256.c 84
-Modules/_hacl/Hacl_Hash_Blake2b_Simd256.c 84
-Modules/_hacl/Hacl_Hash_Blake2s_Simd128.c 84
-Modules/_hacl/Hacl_Hash_Blake2s_Simd128.c 84
-Modules/_hacl/include/krml/FStar_UInt_8_16_32_64.h 4
-Modules/_hashopenssl.c 13
-Modules/_io/_iomodule.c 1
-Modules/_io/bufferedio.c 15
-Modules/_io/bytesio.c 14
-Modules/_io/fileio.c 9
-Modules/_io/stringio.c 8
-Modules/_io/textio.c 17
-Modules/_json.c 19
-Modules/_localemodule.c 2
-Modules/_lsprof.c 5
-Modules/_lzmamodule.c 6
-Modules/_multiprocessing/posixshmem.c 1
-Modules/_multiprocessing/semaphore.c 1
-Modules/_operator.c 5
-Modules/_pickle.c 73
-Modules/_posixsubprocess.c 11
-Modules/_queuemodule.c 4
-Modules/_randommodule.c 3
-Modules/_sqlite/connection.c 5
-Modules/_sqlite/cursor.c 3
-Modules/_sqlite/module.c 2
-Modules/_sre/sre.c 14
-Modules/_sre/sre_lib.h 25
-Modules/_ssl.c 26
-Modules/_struct.c 3
-Modules/_testbuffer.c 27
-Modules/_testcapi/bytes.c 1
-Modules/_testcapi/heaptype.c 1
-Modules/_testcapi/long.c 2
-Modules/_testcapi/mem.c 2
-Modules/_testcapi/monitoring.c 3
-Modules/_testcapi/pyatomic.c 4
-Modules/_testcapi/pyatomic.c 4
-Modules/_testcapi/unicode.c 1
-Modules/_testcapi/vectorcall.c 3
-Modules/_testcapi/watchers.c 3
-Modules/_testcapimodule.c 1
-Modules/_testclinic.c 14
-Modules/_testclinic.c 14
-Modules/_testexternalinspection.c 6
-Modules/_testinternalcapi.c 10
-Modules/_testinternalcapi/test_critical_sections.c 1
-Modules/_testinternalcapi/test_lock.c 4
-Modules/_testlimitedcapi/heaptype_relative.c 3
-Modules/_testlimitedcapi/object.c 2
-Modules/_testlimitedcapi/unicode.c 1
-Modules/_testmultiphase.c 1
-Modules/_tkinter.c 8
-Modules/_xxtestfuzz/_xxtestfuzz.c 1
-Modules/_xxtestfuzz/fuzzer.c 13
-Modules/_zoneinfo.c 17
-Modules/arraymodule.c 48
-Modules/binascii.c 208
-Modules/blake2module.c 8
-Modules/cjkcodecs/_codecs_iso2022.c 1
-Modules/cjkcodecs/_codecs_jp.c 17
-Modules/cjkcodecs/_codecs_kr.c 7
-Modules/cjkcodecs/alg_jisx0201.h 2
-Modules/cjkcodecs/cjkcodecs.h 1
-Modules/cjkcodecs/multibytecodec.c 12
-Modules/expat/pyexpatns.h 3
-Modules/expat/siphash.h 1
-Modules/expat/xmlparse.c 43
-Modules/expat/xmltok.c 15
-Modules/expat/xmltok.c 15
-Modules/expat/xmltok_impl.c 8
-Modules/faulthandler.c 5
-Modules/fcntlmodule.c 6
-Modules/getpath.c 7
-Modules/grpmodule.c 4
-Modules/itertoolsmodule.c 4
-Modules/main.c 2
-Modules/mathmodule.c 14
-Modules/mmapmodule.c 22
-Modules/mmapmodule.c 22
-Modules/posixmodule.c 79
-Modules/pwdmodule.c 4
-Modules/pyexpat.c 10
-Modules/readline.c 1
-Modules/resource.c 4
-Modules/rotatingtree.c 2
-Modules/selectmodule.c 1
-Modules/sha3module.c 4
-Modules/signalmodule.c 3
-Modules/socketmodule.c 75
-Modules/syslogmodule.c 3
-Modules/termios.c 1
-Modules/timemodule.c 10
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-Objects/bytes_methods.c 4
-Objects/bytesobject.c 45
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-Parser/tokenizer/file_tokenizer.c 9
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-Parser/tokenizer/readline_tokenizer.c 4
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-Python/ast_opt.c 5
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-Python/codecs.c 28
-Python/codegen.c 6
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-Python/pystate.c 4
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-Python/sysmodule.c 2
-Python/thread.c 1
-Python/thread_pthread.h 6
-Python/traceback.c 6
-Python/tracemalloc.c 6
+
diff --git a/configure b/configure
index b7055a8f74f..d88acc580b7 100755
--- a/configure
+++ b/configure
@@ -9771,45 +9771,6 @@ then :
 else $as_nop
   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: -Wtrampolines not supported" >&5
 printf "%s\n" "$as_me: WARNING: -Wtrampolines not supported" >&2;}
-fi
-
-  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts -Wconversion" >&5
-printf %s "checking whether C compiler accepts -Wconversion... " >&6; }
-if test ${ax_cv_check_cflags__Werror__Wconversion+y}
-then :
-  printf %s "(cached) " >&6
-else $as_nop
-
-  ax_check_save_flags=$CFLAGS
-  CFLAGS="$CFLAGS -Werror -Wconversion"
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-int
-main (void)
-{
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"
-then :
-  ax_cv_check_cflags__Werror__Wconversion=yes
-else $as_nop
-  ax_cv_check_cflags__Werror__Wconversion=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
-  CFLAGS=$ax_check_save_flags
-fi
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ax_cv_check_cflags__Werror__Wconversion" >&5
-printf "%s\n" "$ax_cv_check_cflags__Werror__Wconversion" >&6; }
-if test "x$ax_cv_check_cflags__Werror__Wconversion" = xyes
-then :
-  CFLAGS_NODIST="$CFLAGS_NODIST -Wconversion"
-else $as_nop
-  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: -Wconversion not supported" >&5
-printf "%s\n" "$as_me: WARNING: -Wconversion not supported" >&2;}
 fi
 
   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts -Wimplicit-fallthrough" >&5
diff --git a/configure.ac b/configure.ac
index ab6233a1341..e83cba49d03 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2514,7 +2514,6 @@ if test "$enable_safety" = "yes"
 then
   AX_CHECK_COMPILE_FLAG([-fstack-protector-strong], [CFLAGS_NODIST="$CFLAGS_NODIST -fstack-protector-strong"], [AC_MSG_WARN([-fstack-protector-strong not supported])], [-Werror])
   AX_CHECK_COMPILE_FLAG([-Wtrampolines], [CFLAGS_NODIST="$CFLAGS_NODIST -Wtrampolines"], [AC_MSG_WARN([-Wtrampolines not supported])], [-Werror])
-  AX_CHECK_COMPILE_FLAG([-Wconversion], [CFLAGS_NODIST="$CFLAGS_NODIST -Wconversion"], [AC_MSG_WARN([-Wconversion not supported])], [-Werror])
   AX_CHECK_COMPILE_FLAG([-Wimplicit-fallthrough], [CFLAGS_NODIST="$CFLAGS_NODIST -Wimplicit-fallthrough"], [AC_MSG_WARN([-Wimplicit-fallthrough not supported])], [-Werror])
   AX_CHECK_COMPILE_FLAG([-Werror=format-security], [CFLAGS_NODIST="$CFLAGS_NODIST -Werror=format-security"], [AC_MSG_WARN([-Werror=format-security not supported])], [-Werror])
   AX_CHECK_COMPILE_FLAG([-Wbidi-chars=any], [CFLAGS_NODIST="$CFLAGS_NODIST -Wbidi-chars=any"], [AC_MSG_WARN([-Wbidi-chars=any not supported])], [-Werror])