Before getting into details, if we cannot find parameter to see compiled options for a particular application, we can use: ldd tool, to see library dependencies (it can be inaccurate when it is a dependency from another library). 

An example for finding dependencies with ldd (for smbd binary from Samba):

# ldd /usr/local/sbin/smbd  

To see compiled options within Postfix:

You will see something like that:

btree

cidr

environ

hash

mysql

pcre

proxy

regexp

static

unix

To see options compiled with Squid:

You will see something like this:

Squid Cache: Version 2.6.STABLE12

configure options: '--bindir=/usr/local/sbin' '--sbindir=/usr/local/sbin' '--datadir=/usr/local/etc/squid' '--libexecdir=/usr/local/libexec/squid' '--localstatedir=/usr/local/squid' '--sysconfdir=/usr/local/etc/squid' '--enable-removal-policies=lru heap' '--disable-linux-netfilter' '--disable-linux-tproxy' '--disable-epoll' '--enable-auth=basic ntlm digest' '--enable-basic-auth-helpers=NCSA PAM MSNT SMB SASL YP' '--enable-digest-auth-helpers=password' '--enable-external-acl-helpers=ip_user session unix_group wbinfo_group' '--enable-ntlm-auth-helpers=SMB' '--enable-storeio=ufs diskd null' '--enable-delay-pools' '--enable-snmp' '--enable-cache-digests' '--enable-referer-log' '--enable-useragent-log' '--enable-arp-acl' '--enable-pf-transparent' '--enable-follow-x-forwarded-for' '--enable-icap-support' '--enable-kqueue' '--with-large-files' '--enable-large-cache-files' '--enable-err-languages=Azerbaijani Bulgarian Catalan Czech Danish Dutch  English Estonian Finnish French German Greek Hebrew  Hungarian Italian Japanese Korean Lithuanian  Polish Portuguese Romanian Russian-1251 Russian-koi8-r  Serbian Simplify_Chinese Slovak Spanish Swedish  Traditional_Chinese Turkish' '--enable-default-err-language=English' '--prefix=/usr/local' 'i386-portbld-freebsd6.2' 'CC=cc' 'CFLAGS=-O2 -fno-strict-aliasing -pipe  -I/usr/local/include' 'CPPFLAGS=-I/usr/local/include' 'LDFLAGS= -L/usr/local/lib' 'build_alias=i386-portbld-freebsd6.2' 'host_alias=i386-portbld-freebsd6.2' 'target_alias=i386-portbld-freebsd6.2'

To see options compiled with Proftpd:

(or proftpd --settings)

You will see something like this:

Compile-time Settings:

  Version: 1.3.1rc2

  Platform: FREEBSD6 (FREEBSD6_2)

  Built With:

    configure --localstatedir=/var/run --sysconfdir=/usr/local/etc --enable-builtin-getnameinfo --disable-sendfile --disable-ipv6 --with-modules=mod_ratio:mod_sql:mod_sql_mysql:mod_codeconv:mod_ifsession --with-includes=:/usr/local/include:/usr/local/include/mysql:/usr/local/include --with-libraries=:/usr/local/lib/mysql --prefix=/usr/local i386-portbld-freebsd6.2

  CFLAGS: -O2 -fno-strict-aliasing -pipe  -Wall

  LDFLAGS: -L$(top_srcdir)/lib

  LIBS: -lsupp -lcrypt -liconv -L/usr/local/lib -lutil

Features:

    - Autoshadow support

    - Controls support

    + curses support

    - Developer support

    - DSO support

    - IPv6 support

    + Largefile support

    - NLS support

    - Lastlog support

    - NLS support

    + ncurses support

    - OpenSSL support

    - POSIX ACL support

    - Shadow file suppport

    - Sendfile support

    + Trace support

To see options compiled with Samba:

You will see a lot of informations and also:

Builtin modules:

    pdb_ldap pdb_smbpasswd pdb_tdbsam rpc_lsa rpc_reg rpc_lsa_ds rpc_wks rpc_svcctl rpc_ntsvcs rpc_net rpc_netdfs rpc_srv rpc_spoolss rpc_eventlog rpc_samr idmap_ldap idmap_tdb auth_sam auth_unix auth_winbind auth_server auth_domain auth_builtin