[RTEMS Project] #4631: RSB fails to build gdb on Fedora 35

[RTEMS trac]

#4631: RSB fails to build gdb on Fedora 35
-----------------------------+--------------------
  Reporter:  Frank Kuehndel  |      Owner:  (none)
      Type:  defect          |     Status:  new
  Priority:  normal          |  Milestone:  6.1
 Component:  tool/gdb        |    Version:  6
  Severity:  normal          |   Keywords:
Blocked By:                  |   Blocking:
-----------------------------+--------------------
 The rtems-source-builder fails to build the tools in a Fedora 35
 container. I am building ARM for RTEMS 6 and get this error message:

 {{{
 config: tools/rtems-gdb-11.2.cfg
 error: shell macro failed: /home/minna/src/rtems-source-builder/source-
 builder/sb/rtems-build-dep -c gcc  -l : 2: error: no library (-l) provided
 Build Set: Time 0:00:33.396165
 }}}

 The same error appears for other architectures like AARCH64, POWERPC,
 RISCV on Fedora 35. The source for this error is in file `source-
 builder/config/gdb-common-1.cfg` in line 118:

 {{{
    104  %ifnos darwin
    105    %if %{host_ldflags} == %{nil}
    106      %define gdb-host-libs %{nil}
    107    %else
    108      %define gdb-host-libs -L '%{host_ldflags}'
    109    %endif
    110    %if %{gdb-python-config} != %{nil}
    111      %define gdb-python-lib-filter awk 'BEGIN{FS="
 "}/python/{for(i=1;i<NF;++i)if(match($i,".*lpython.*")) print
 "lib"substr($i,3)"*";}'
    112      %if %{gdb-python-ver-mm} < 3.8
    113          %define gdb-python-config-lib-check-flags --ldflags
    114      %else
    115          %define gdb-python-config-lib-check-flags --ldflags
 --embed
    116      %endif
    117      %define gdb-python-config-libs %(%{gdb-python-config} %{gdb-
 python-config-lib-check-flags} | %{gdb-python-lib-filter})
    118      %define gdb-python-lib-check %(%{_sbdir}/sb/rtems-build-dep -c
 %{__cc} %{gdb-host-libs} -l %{gdb-python-config-libs})
    119    %else
    120      %define gdb-python-lib-check %(%{_sbdir}/sb/rtems-build-dep -c
 %{__cc} %{gdb-host-libs} -l %{gdb-python-ver-lib})
    121    %endif
    122    %if %{gdb-python-lib-check} == not-found &&
 !%{_rsb_getting_source}
    123      %error "gdb: python: library file not found: %{gdb-python-ver-
 lib}, please install"
    124    %endif
    125  %endif
 }}}

 Some values of involved variables:

 {{{
 gdb-python-ver-mm = 3.10
 gdb-python-config = /usr/bin/python3-config
 gdb-python-config-lib-check-flags = --ldflags
 gdb-python-lib-filter = awk 'BEGIN{FS="
 "}/python/{for(i=1;i<NF;++i)if(match($i,".*lpython.*")) print
 "lib"substr($i,3)"*";}'
 gdb-python-config-libs = ''
 }}}

 The trouble is that `gdb-python-config-libs` is empty when line 118 gets
 called. It is empty because there is no `python`-library in the output of
 this call on Fedora 35:

 {{{
 $ /usr/bin/python3-config --ldflags
  -L/usr/lib64  -lcrypt -ldl  -lm -lm
 }}}

 Just to compare, on OpenSUSE 15.3 the same call returns (note the
 `-lpython3.6m `):

 {{{
 $ /usr/bin/python3-config --ldflags
  -L/usr/lib64 -lpython3.6m -lpthread -ldl  -lutil -lm  -Xlinker -export-
 dynamic
 }}}

 Commenting out line 118 makes the build go through smoothly but I would
 prefer a permanent fix.

 * Would be skipping line 118 when `gdb-python-config-libs` is empty be an
 appropriate solution?
 * Is the "real" error in line 112? (`%if 3.10 < 3.8` evaluates
 unexpectedly to `true`)
 * Would the "error" in line 123 print out the correct library name?
 * Does the whole check make sense when `python3-config` is obviously
 installed (both the command and the library are "usually" in the same
 `pythonX-devel` package)?

 Notes:

 * On Fedora 35 `/usr/lib64/libpython3.10.so` exists.
 * On Fedora 35 adding `--embed` provides the library:

 {{{
 $ /usr/bin/python3-config --ldflags --embed
  -L/usr/lib64 -lpython3.10 -lcrypt -ldl  -lm -lm
 }}}

 For the records:

 Command:

 {{{
 ../source-builder/sb-set-builder --rtems-version 6 --prefix /opt/rtems/6
 --with_cxx --with_fortran --with_objc --jobs=12 --log ~/sb-set-builder.log
 6/rtems-arm
 }}}

 RTEMS rtems-source-builder git: `6fe98f91d94bbf965bc0e78015585ff8823d17bd`
 RTEMS: 6
 Target architecture: ARM
 Host architecture: x86_64
 Hoast Kernel: `5.3.18-150300.59.49-default`
 OS: Fedora Linux 35 (Container Image)
 Container image base: `docker.io/library/fedora:latest`
 Python version in container: 3.10.2
 Test date: 2022-03-18T11:02:10+01:00
 `rtems-source-builder/source-builder/sb-check` log:

 {{{
 RTEMS Source Builder - Check, 6 (6fe98f91d94b modified)
 warning: exe: absolute exe found in path: (__chown) /usr/sbin/chown
 warning: exe: absolute exe found in path: (__install_info) /usr/bin
 /install-info
 Environment is ok
 }}}

--
Ticket URL: <http://devel.rtems.org/ticket/4631>
RTEMS Project <http://www.rtems.org/>
RTEMS Project