I didn't formalise the tests last night, but see the attached file,
which passes cleanly on NetBSD and the illumos gate.

On musl with 1/2 I get
$ ~/store/code/musl/prefix/bin/musl-clang tst-reg-startend.c -o \
    /tmp/tst-reg-startend  -DSTANDALONE  -static &&
	/tmp/tst-reg-startend 2>&1 | cat -A
tst-reg-startend.c: ^a.c$: ac: no match
tst-reg-startend.c: ^a.*c$: ac: no match
tst-reg-startend.c: ^a[^c]c$: ac: no match
tst-reg-startend.c: ^a..: ac: no match
tst-reg-startend.c: ..c: ac: no match
tst-reg-startend.c: [^z]c: ac: no match
tst-reg-startend.c: [^z]c: ac: wanted {2, 4}, got {1, 4}

And with 2/2 it passes cleanly.


glibc gives me a host of errors, but I'll post fixes and include this
test there later.

Best,
наб

Please keep me in CC.