Re: compile error for handwritten "perl-RPM2", 'RPM_GNUC_NULL_TERMINATED' error

Robert P. J. Day
2016-11-08T11:18:41Z

replying to my earlier post with additional info ... man, i want to
debug this ...

On Tue, 8 Nov 2016, Robert P. J. Day wrote:

> following on my earlier post, here's the specific issue i'm
> tackling. having found no existing OE recipe equivalent to a centos
> "perl-RPM2" RPM, i wrote my own. here's the info about that RH RPM on
> my fedora system, so i know what the final result should look like:
>
> $ rpm -ql perl-RPM2
> /usr/lib64/perl5/vendor_perl/RPM2.pm
> /usr/lib64/perl5/vendor_perl/auto/RPM2
> /usr/lib64/perl5/vendor_perl/auto/RPM2/RPM2.so
> /usr/share/doc/perl-RPM2
> /usr/share/doc/perl-RPM2/Changes
> /usr/share/doc/perl-RPM2/README
> /usr/share/man/man3/RPM2.3pm.gz
> $
>
> so, as before, track down the source at cpan:
>
> https://metacpan.org/pod/RPM2
>
> and write a boilerplate recipe, "perl-rpm2", containing the following
> line since it's an older style recipe:
>
> inherit cpan_build
>
> fetching works fine:
>
> $ bitbake -c fetchall perl-rpm2
>
> but here's the problem:
>
> $ bitbake perl-rpm2
>
> ... snip ...
>
> | DEBUG: Executing shell function do_compile
> | Copying lib/RPM2.pm -> blib/lib/RPM2.pm
> | lib/RPM2.xs -> lib/RPM2.c
> | powerpc-poky-linux-gcc -m32 -mhard-float -mcpu=7400 -mno-spe
> --sysroot=/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc
> -I/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc/usr/lib/perl/5.22.1/CORE
> -DVERSION="1.3" -DXS_VERSION="1.3" -fPIC -DRPM2_API=5004
> -I/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc/usr/include/rpm
> -c -O2 -pipe -g -feliminate-unused-debug-types
> -fdebug-prefix-map=/home/rpjday/oe/builds/msm_qemuppc/tmp/work/ppc7400-poky-linux/perl/5.22.1-r0=/usr/src/debug/perl/5.22.1-r0
> -fdebug-prefix-map=/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/x86_64-linux=
> -fdebug-prefix-map=/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc=
> -DDEBIAN -D_REENTRANT -D_GNU_SOURCE -fwrapv -fno-strict-aliasing -pipe
> -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2 -O2
> -pipe -g -feliminate-unused-debug-types
> -fdebug-prefix-map=/home/rpjday/oe/builds/msm_qemuppc/tmp/work/ppc7400-poky-linux/perl-rpm2/1.3-r0=/usr/src/debug/perl-rpm2/1.3-r0
> -fdebug-prefix-map=/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/x86_64-linux=
> -fdebug-prefix-map=/home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc=
> -O2 -o lib/RPM2.o lib/RPM2.c
> | In file included from
> /home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc/usr/include/rpm/rpmcli.h:9:0,
> | from lib/RPM2.xs:3:
> |
> /home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc/usr/include/rpm/rpmmacro.h:
> In function 'rpmExpand':
> |
> /home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc/usr/include/rpm/rpmmacro.h:249:2:
> error: expected declaration specifiers before
> 'RPM_GNUC_NULL_TERMINATED'
> | RPM_GNUC_NULL_TERMINATED
> | ^~~~~~~~~~~~~~~~~~~~~~~~
> |
> /home/rpjday/oe/builds/msm_qemuppc/tmp/sysroots/qemuppc/usr/include/rpm/rpmmacro.h:260:2:
> error: expected '=', ',', ';', 'asm' or '__attribute__' before
> 'RPM_GNUC_NULL_TERMINATED'
> | RPM_GNUC_NULL_TERMINATED
> | ^~~~~~~~~~~~~~~~~~~~~~~~
>
> ... big snip, lots more errors ...

ok, here's my wildly-uneducated record of what is going on:

first, unpacking and configuring perl-RPM2 source (and running XS
processor) gives me the source file "lib/RPM2.c" (which is what is
generating the first build error above), which includes the header
file:

#include <rpm/rpmcli.h>

next, wander over to the qemuppc sysroot, to usr/include/rpm/, to
check out that header file, which contains (among other things):

#include <popt.h>
#include <rpmmacro.h> <----- there
#include <rpmtypes.h>
#include <rpmtag.h>
#include <rpmps.h>
#include <rpmrc.h>
#include <rpmfi.h> /* XXX rpmfileAttrs */
#include <rpmts.h> /* XXX rpmdepFlags *

next, in the same directory, examine rpmmacro.h, which contains:

#if defined(_MACRO_INTERNAL)
#include <rpmiotypes.h>
... snip ...

at this point, inclusion is now conditional on _MACRO_INTERNAL, so
move on to rpmiotypes.h, which contains:

#include <rpmutil.h>

and finally visit that header file in the qemuppc sysroot to find:

#if __GNUC__ >= 4
#define RPM_GNUC_NULL_TERMINATED __attribute__((__sentinel__))
#else
#define RPM_GNUC_NULL_TERMINATED
#endif

where we find the definition of that macro.

now, is it my imagination, or could a lot of this compile-time error
be resolved by simply defining the macro "_MACRO_INTERNAL" for the
build? and if so, what is the proper way to add that setting to the
compile step for this recipe?

would i use the standard EXTRA_* variables? or are there
perl-specific variables one would use when build CPAN recipes? or am i
totally off-track here?

rday