diff -up ./config.m4.noatfork ./config.m4
--- ./config.m4.noatfork	2022-07-07 07:30:58.524647576 +0200
+++ ./config.m4	2022-07-07 07:32:01.490513120 +0200
@@ -1379,7 +1379,6 @@ if test "$PHP_GRPC" != "no"; then
     , $ext_shared, , -fvisibility=hidden \
     -DOPENSSL_NO_ASM -D_GNU_SOURCE -DWIN32_LEAN_AND_MEAN \
     -D_HAS_EXCEPTIONS=0 -DNOMINMAX -DGRPC_ARES=0 \
-    -DGRPC_POSIX_FORK_ALLOW_PTHREAD_ATFORK=1 \
     -DGRPC_XDS_USER_AGENT_NAME_SUFFIX='"\"PHP\""' \
     -DGRPC_XDS_USER_AGENT_VERSION_SUFFIX='"\"1.66.0RC3\""')