Build errors in GNATS 4.2.0 on Ubuntu 20.04.2 LTS

[John P. Willis]

Hello all,

When attempting to build GNATS 4.2.0 on Ubuntu 20.04.2 LTS, I get the
following error:

mail.c: In function ‘get_responsible_address’:
mail.c:70:40: error: comparison between pointer and zero character 
constant [-Werror=pointer-compare]
   70 |    res->admFields[ResponsibleAdmAlias] == '\0')
      |                                        ^~
mail.c:70:4: note: did you mean to dereference the pointer?
   70 |    res->admFields[ResponsibleAdmAlias] == '\0')
      |    ^
cc1: all warnings being treated as errors
make[3]: *** [Makefile:862: mail.o] Error 1
make[3]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats'
make[2]: *** [Makefile:953: all-recursive] Error 1
make[2]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats'
make[1]: *** [Makefile:583: all] Error 2
make[1]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats'
make: *** [Makefile:453: all-recursive] Error 1

The GCC version info is as follows:

root@test:/usr/local/src/gnats-4.2.0# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/9/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none:hsa
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 
9.3.0-17ubuntu1~20.04' 
--with-bugurl=file:///usr/share/doc/gcc-9/README.Bugs 
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++,gm2 
--prefix=/usr --with-gcc-major-version-only --program-suffix=-9 
--program-prefix=x86_64-linux-gnu- --enable-shared 
--enable-linker-build-id --libexecdir=/usr/lib 
--without-included-gettext --enable-threads=posix --libdir=/usr/lib 
--enable-nls --enable-clocale=gnu --enable-libstdcxx-debug 
--enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new 
--enable-gnu-unique-object --disable-vtable-verify --enable-plugin 
--enable-default-pie --with-system-zlib --with-target-system-zlib=auto 
--enable-objc-gc=auto --enable-multiarch --disable-werror 
--with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 
--enable-multilib --with-tune=generic 
--enable-offload-targets=nvptx-none=/build/gcc-9-HskZEa/gcc-9-9.3.0/debian/tmp-nvptx/usr,hsa 
--without-cuda-driver --enable-checking=release --build=x86_64-linux-gnu 
--host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 9.3.0 (Ubuntu 9.3.0-17ubuntu1~20.04)


The system info is as follows:


root@test:/usr/local/src/gnats-4.2.0# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 20.04.2 LTS
Release:        20.04
Codename:       focal



I attempted changing gnats/mail.c:70 to the following, casting the '\0' 
to a char * (as res->admFields is a char **):

res->admFields[ResponsibleAdmAlias] == (char *) '\0')

And attempted compiling again. This got through mail.c, but resulted in 
the following error:

misc.c: In function ‘log_msg’:
misc.c:106:7: error: this statement may fall through 
[-Werror=implicit-fallthrough=]
  106 |    if (gnats_logfile != (FILE *)NULL)
      |       ^


At this point, I figured that the modern GCC's -Wall -Werror, etc. have 
gotten pickier since 2015 (I have encountered this in my own projects), 
thus I tried changing line 284 of configure.ac to the following:

GCC_CFLAGS="-ansi"

(removing -Werror and -Wall)

and running "autoreconf" in the root of the repository, followed by the 
usual ./configure; make clean; make incantation. That results in the 
following:

make[4]: Entering directory '/usr/local/src/gnats-4.2.0/gnats/ds-file'
depbase=`echo gen-index.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
gcc -DHAVE_CONFIG_H 
-DGNATSD_USER_ACCESS_FILE=\"/usr/local/etc/gnats/gnatsd.user_access\" 
-DGNATSD_HOST_ACCESS_FILE=\"/usr/local/etc/gnats/gnatsd.host_access\" 
-DDEFAULT_GNATS_SERVICE=\"\" 
-DGLOBAL_DB_LIST_FILE=\"/usr/local/etc/gnats/databases\" 
-DGNATS_USER=\"gnats\" -I. -I../../gnats  -I ../../gnats  -ansi -Wextra 
-Wpedantic -Wno-error=format -Wno-unused-result -Wwrite-strings 
-Wmissing-prototypes -Wstrict-prototypes -g -O2 -fno-unit-at-a-time -MT 
gen-index.o -MD -MP -MF $depbase.Tpo -c -o gen-index.o gen-index.c &&\
mv -f $depbase.Tpo $depbase.Po
make[4]: *** No rule to make target '../libgnats.a', needed by 
'gen-index'.  Stop.
make[4]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats/ds-file'
make[3]: *** [Makefile:1347: query-pr.o] Error 2
make[3]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats'
make[2]: *** [Makefile:985: all-recursive] Error 1
make[2]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats'
make[1]: *** [Makefile:610: all] Error 2
make[1]: Leaving directory '/usr/local/src/gnats-4.2.0/gnats'
make: *** [Makefile:465: all-recursive] Error 1


So it appears that a good deal of work needs to be done to bring GNATS 
forward and make it compile properly on current systems.

Should I attempt to go further, or are the GNATS developers already 
working on something in an official capacity? I noticed that GNATS is 
also gone from the Debian and Ubuntu apt repositories, since Jessie.

Cheers,


--
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 * John P. Willis
 * Coherent Logic Development LLC
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