First, I needed to install Veewee by following instructions.
rbenv install 1.9.2-p320
Last 10 log lines:
ossl_pkey_ec.c:819:29: note: each undeclared identifier is reported only once for each function it appears in
ossl_pkey_ec.c: In function ‘ossl_ec_group_set_seed’:
ossl_pkey_ec.c:1114:89: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (EC_GROUP_set_seed(group, (unsigned char *)RSTRING_PTR(seed), RSTRING_LEN(seed)) != RSTRING_LEN(seed))
/usr/bin/gcc -I. -I../../.ext/include/x86_64-linux -I../.././include -I../.././ext/openssl -DRUBY_EXTCONF_H=\"extconf.h\" -I/home/jyrki/.rbenv/versions/1.9.2-p320/include -fPIC -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -o ossl_cipher.o -c ossl_cipher.c
make: *** [ossl_pkey_ec.o] Error 1
make: *** Waiting for unfinished jobs....
make: Leaving directory `/tmp/ruby-build.20140418062211.18615/ruby-1.9.2-p320/ext/openssl'
make: *** [mkmain.sh] Error 1
This is a known issue, which can be fixed by patching rbenv. Note that the patch contains changes to test/openssl/test_pkey_ec.rb, which doesn't seem to be present on 1.9.2-p320. So the command found from issue description needs some modifications.
curl -fsSL https://bugs.ruby-lang.org/projects/ruby-trunk/repository/revisions/41808/diff?format=diff | filterdiff -x ChangeLog -x test/openssl/test_pkey_ec.rb | rbenv install --patch 1.9.2-p320(edit: Reported as ruby-build #555)
Note that running this requires filterdiff command from patchutil -package.
After that, rest of the installation went smoothly.