sysdep.c:667:11: warning: 'vfork' is deprecated: Use posix_spawn or fork [-Wdeprecated-declarations]
pid = vfork ();
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/unistd.h:604:1: note: 'vfork' has been explicitly marked deprecated here
__deprecated_msg("Use posix_spawn or fork")
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/sys/cdefs.h:208:48: note: expanded from macro '__deprecated_msg'
#define __deprecated_msg(_msg) __attribute__((__deprecated__(_msg)))
^
1 warning generated.

callproc.c:1478:11: warning: 'vfork' is deprecated: Use posix_spawn or fork [-Wdeprecated-declarations]
pid = vfork ();
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/unistd.h:604:1: note: 'vfork' has been explicitly marked deprecated here
__deprecated_msg("Use posix_spawn or fork")
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/sys/cdefs.h:208:48: note: expanded from macro '__deprecated_msg'
#define __deprecated_msg(_msg) __attribute__((__deprecated__(_msg)))
^
1 warning generated.

————————————————————————————————————————————————

This is by no means breaking or disrupting anything on my end (at least that I can tell), but I did notice in some commit messages a few weeks that someone was attempting to replace vfork with posix_spawn specifically on macOS, so maybe my system is some unhandled corner-case?

commit cc4edea872ca653f3e0631ce50e47b5260c6773a

Author: Philipp Stephani <phst@google.com>

Date: Wed Dec 30 14:42:01 2020 +0100

Use posix_spawn if possible.

posix_spawn is less error-prone than vfork + execve, and can make

better use of system-specific enhancements like 'clone' on Linux. Use

it if we don't need to configure a pseudoterminal.

Backported from commit a60053f8368e058229721f1bf1567c2b1676b239.

Unlike that commit, only define USABLE_POSIX_SPAWN on macOS, because

there posix_spawn is much faster than vfork.