Warnings from clang 7.0 when compiling dovecot-openssl-common.c from dovecot 2.3.5 with openssl 1.1.1a.
This is dovecot's configuration:
config_options="--prefix=$prefix \
--sysconfdir=$prefix/etc \
--datarootdir=$prefix/share \
--mandir=$man \
--docdir=$doc \
--with-docs \
--with-ssl=openssl --with-ssldir=$prefix/etc \
--with-sodium \
--with-libiconv-prefix=/opt/libiconv \
\
--with-bzlib=no \
--with-gssapi=no \
--with-ldap=no \
--with-lucene=no \
--with-lz4=no \
--with-lzma=no \
--with-pam=no \
--with-solr=no \
--with-sql=no \
--with-vpopmail=no \
--with-zlib=no \
\
--enable-dependency-tracking";
Note on passing: --with-ssldir=$prefix/etc is ignored by the configurator, as it forces $prefix/etc/dovecot.