make check segfaults when no USER variable is set

[felixfrank]

Tried installing czmq in an archlinux docker container, using the standard:
./autogen.sh && ./configure --prefix=... && make check
However the tests always segfaulted.
After running make debug I found out the exact line, which is in:

czmq/src/zproxy.c

Line 563 in f5475cc

if (streq(getenv("USER"), "vagrant"))

printenv shows no USER variable and running the make check with a user variable makes the test succeed:
env USER="xyz" make check

Maybe there's a tiny workaround for that?

[bluca]

I guess it should do instead something like:

if (getenv("USER") && streq(getenv("USER"), "vagrant"))

IIRC strcmp barfs if one of the pointers is NULL which is probably what you are seeing. Could you please send a PR?

[wesyoung]

bah- that's on me- should have thought about that a bit better (or at-least tested it) when i added it.