libdap @3.15.1: error: ordered comparison between pointer and zero ('char *' and 'int')

[basmac]

using Hi Sierra Dev 1 update and Command Line Tools for 10.13
end of debug -

libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-BaseType.lo -MD -MP -MF .deps/libdap_la-BaseType.Tpo -c BaseType.cc  -fno-common -DPIC -o .libs/libdap_la-BaseType.o
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-Int32.lo -MD -MP -MF .deps/libdap_la-Int32.Tpo -c Int32.cc  -fno-common -DPIC -o .libs/libdap_la-Int32.o
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-DAS.lo -MD -MP -MF .deps/libdap_la-DAS.Tpo -c DAS.cc -o libdap_la-DAS.o >/dev/null 2>&1
DDXParserSAX2.cc:1244:40: error: ordered comparison between pointer and zero ('char *' and 'int')
        while ((fgets(chars, size, in) > 0) && !is_boundary(chars, boundary)) {
                ~~~~~~~~~~~~~~~~~~~~~~ ^ ~
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-DataDDS.lo -MD -MP -MF .deps/libdap_la-DataDDS.Tpo -c DataDDS.cc -o libdap_la-DataDDS.o >/dev/null 2>&1
1 error generated.
make[2]: *** [libdap_la-DDXParserSAX2.lo] Error 1
make[2]: *** Waiting for unfinished jobs....
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-Byte.lo -MD -MP -MF .deps/libdap_la-Byte.Tpo -c Byte.cc -o libdap_la-Byte.o >/dev/null 2>&1
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-Int32.lo -MD -MP -MF .deps/libdap_la-Int32.Tpo -c Int32.cc -o libdap_la-Int32.o >/dev/null 2>&1
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-BaseType.lo -MD -MP -MF .deps/libdap_la-BaseType.Tpo -c BaseType.cc -o libdap_la-BaseType.o >/dev/null 2>&1
mv -f .deps/libdap_la-DAS.Tpo .deps/libdap_la-DAS.Plo
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-AttrTable.lo -MD -MP -MF .deps/libdap_la-AttrTable.Tpo -c AttrTable.cc -o libdap_la-AttrTable.o >/dev/null 2>&1
mv -f .deps/libdap_la-DataDDS.Tpo .deps/libdap_la-DataDDS.Plo
mv -f .deps/libdap_la-Byte.Tpo .deps/libdap_la-Byte.Plo
mv -f .deps/libdap_la-Int32.Tpo .deps/libdap_la-Int32.Plo
libtool: compile:  /usr/bin/clang++ -DHAVE_CONFIG_H -I. -I./gl -I./gl -I./GNU -I/opt/local/include/libxml2 -I/opt/local/include -pipe -Os -stdlib=libc++ -arch x86_64 -MT libdap_la-DDS.lo -MD -MP -MF .deps/libdap_la-DDS.Tpo -c DDS.cc -o libdap_la-DDS.o >/dev/null 2>&1
mv -f .deps/libdap_la-BaseType.Tpo .deps/libdap_la-BaseType.Plo
mv -f .deps/libdap_la-AttrTable.Tpo .deps/libdap_la-AttrTable.Plo
mv -f .deps/libdap_la-DDS.Tpo .deps/libdap_la-DDS.Plo
make[2]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_science_libdap/libdap/work/libdap-3.15.1'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_science_libdap/libdap/work/libdap-3.15.1'
make: *** [all] Error 2
make: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_science_libdap/libdap/work/libdap-3.15.1'
Command failed:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_science_libdap/libdap/work/libdap-3.15.1" && /usr/bin/make -j8 -w all
Exit code: 2
Error: Failed to build libdap: command execution failed
DEBUG: Error code: CHILDSTATUS 70749 2
DEBUG: Backtrace: command execution failed
    while executing
"system {*}$notty {*}$nice $fullcmdstring"
    invoked from within
"command_exec build"
    (procedure "portbuild::build_main" line 8)
    invoked from within
"$procedure $targetname"
Error: See /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_science_libdap/libdap/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets to report a bug.
Error: Processing of port libdap failed
[mac27:/] root#

[raimue (Rainer Müller)]

As this is due to the stricter compiler, I assume this also affects Sierra with Xcode 9.