I built openssl-1.0.1-beta1 on OpenVOS Release 17.1.0at using the "vos-gcc" entry in Configure, along with some extra arguments (see below).
It successfully built and passed all relevant self-tests.
However, several source files reference str(n)casecmp without including <strings.h>. Since the implicit declaration of str(n)casecmp is sufficient, I've just ignored this error.
Details for the curious:
The str(n)casecmp functions are XSI extensions to POSIX. The POSIX standard only requires them to be declared in strings.h. It appears that the BSD variants of Unix declare them in <string.h>; this header is commonly included within openssl. No openssl headers include <strings.h>. I have no idea whether all of the platforms supported by openssl provide this header file, and so I'm not proposing to add it now; perhaps it could be added in the HEAD development branch.
The source files that reference str(n)casecmp in our build are:
crypto/engine/tb_asnmth.c (line 192)
crypto/asn1/ameth_lib.c (line 234)
crypto/x509v3/v3_ncons.c (lines 408, 494)
apps/ca.c (line 2729)
Here is the output of Configure, omitting noise from setting various environment variables: