Bug 240571

Summary:	m4 divert( X-with-spaces ) -> argument is invalid
Product:	Base System	Reporter:	John Kennedy <warlock>
Component:	bin	Assignee:	freebsd-bugs (Nobody) <bugs>
Status:	New ---
Severity:	Affects Some People
Priority:	---
Version:	12.0-STABLE
Hardware:	amd64
OS:	Any

Description John Kennedy 2019-09-13 20:53:40 UTC

For 12/stable (now 12.1-PRERELEASE) between r352217 and r352298 (and I presume the MFC of r352065-r352070 in r352277), m4 lost it's ability to divert( -1 ) to ignore an input stream.  Note the spaces around the number.

# grep '^FreeBSD 12' /.zfs/snapshot/2019-09-13-10:54:12/etc/motd /etc/motd
/.zfs/snapshot/2019-09-13-10:54:12/etc/motd:FreeBSD 12.1-PRERELEASE (GENERIC) #106 r352217+0e6a9a9426c7(stable/12): Wed Sep 11 10:30:02 PDT 2019
/etc/motd:FreeBSD 12.1-PRERELEASE (GENERIC) #108 r352298+2356cf5555c7(stable/12): Fri Sep 13 10:49:27 PDT 2019

# cat /tmp/m4.txt 
begin
divert(-1)dnl
middle
divert( -1 )dnl
foo
divert(0)dnl
end

# m4 < /tmp/m4.txt 
begin
m4: stdin at line 4: divert: argument is invalid: -1 .

# /.zfs/snapshot/2019-09-13-10:54:12/usr/bin/m4 < /tmp/m4.txt 
begin
end