Compilation of (part of) libpam fails on SunOS 5.11 oi_151a7 (OpenIndiana)

_From @ThomasHabets on October 10, 2014 8:6_

Original [issue 234](https://code.google.com/p/google-authenticator/issues/detail?id=234) created by olaf.lists on 2012-12-19T09:50:55.000Z:

-> What steps will reproduce the problem?
1. Download either current repository or released package
2a. CC=/opt/gcc/4.4.4/bin/gcc make (to use gcc-illumos 4.4.4)
2b modify Makefile to remove -fvisibility=hidden option, then "make" (to use gcc 3.4.3)

-> What is the expected output? What do you see instead?
## Compilation complete expected, but instead:

olaf@openindiana:~/tools/libpam-google-authenticator-1.0$ CC=/opt/gcc/4.4.4/bin/gcc make
/opt/gcc/4.4.4/bin/gcc --std=gnu99 -Wall -O2 -g -fPIC -c -D_POSIX_PTHREAD_SEMANTICS -D_REENTRANT -fvisibility=hidden -o google-authenticator.o google-authenticator.c
/opt/gcc/4.4.4/bin/gcc --std=gnu99 -Wall -O2 -g -fPIC -c -D_POSIX_PTHREAD_SEMANTICS -D_REENTRANT -fvisibility=hidden -o base32.o base32.c
/opt/gcc/4.4.4/bin/gcc --std=gnu99 -Wall -O2 -g -fPIC -c -D_POSIX_PTHREAD_SEMANTICS -D_REENTRANT -fvisibility=hidden -o hmac.o hmac.c
/opt/gcc/4.4.4/bin/gcc --std=gnu99 -Wall -O2 -g -fPIC -c -D_POSIX_PTHREAD_SEMANTICS -D_REENTRANT -fvisibility=hidden -o sha1.o sha1.c
/opt/gcc/4.4.4/bin/gcc -g -mimpure-text -o google-authenticator google-authenticator.o base32.o hmac.o sha1.o -ldl
/opt/gcc/4.4.4/bin/gcc --std=gnu99 -Wall -O2 -g -fPIC -c -D_POSIX_PTHREAD_SEMANTICS -D_REENTRANT -fvisibility=hidden -o pam_google_authenticator.o pam_google_authenticator.c
pam_google_authenticator.c: In function ‘converse’:
pam_google_authenticator.c:121: warning: passing argument 2 of ‘conv->conv’ from incompatible pointer type
pam_google_authenticator.c:121: note: expected ‘struct pam_message *_’ but argument is of type ‘const struct pam_message *_’
pam_google_authenticator.c: In function ‘get_first_pass’:
pam_google_authenticator.c:765: warning: passing argument 3 of ‘pam_get_item’ from incompatible pointer type
/usr/include/security/pam_appl.h:186: note: expected ‘void *_’ but argument is of type ‘const void *_’
pam_google_authenticator.c: In function ‘request_pass’:
pam_google_authenticator.c:776: warning: initialization discards qualifiers from pointer target type
/opt/gcc/4.4.4/bin/gcc -shared -g -mimpure-text -o pam_google_authenticator.so pam_google_authenticator.o base32.o hmac.o sha1.o -lpam
/opt/gcc/4.4.4/bin/gcc --std=gnu99 -Wall -O2 -g -fPIC -c -D_POSIX_PTHREAD_SEMANTICS -D_REENTRANT -fvisibility=hidden -o demo.o demo.c
demo.c: In function ‘pam_get_item’:
demo.c:97: warning: initialization from incompatible pointer type
demo.c: At top level:
demo.c:106: error: conflicting types for ‘pam_set_item’
/usr/include/security/pam_appl.h:175: note: previous declaration of ‘pam_set_item’ was here
## make: **\* [demo.o] Error 1

that means, apparently important warnings in the pam_google_authenticator.c file and an real error in demo.c.
In a software that concerns security, I would feel safer if warnings were all taken care of.

-> What version of the product are you using? On what operating system?
Released version or current development version on SunOS 5.11 oi_151a7 (OpenIndiana)

_Copied from original issue: google/google-authenticator#233_