[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[andrew at ishiboo dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

--- Comment #26 from Andrew Paprocki <andrew at ishiboo dot com> ---
Just re-summarizing now for 2020 since there have been a few twists and turns
and distractions.

This issue has nothing to do with CMake, -brtl, or -bexpall linker flags. This
issue only occurs when GCC is told to pass the -bsvr4 linker flag, because the
application wishes to use multiple -R parameters as documented in the man page
(see comment 14). When that occurs, the error in this ticket happens.

The already applied patches to GCC mentioned throughout the bug do not change
any behavior -- it still fails to link.

David, can you or someone on the linker team determine if this is an issue with
the GCC side of things, or it is simply a bug in the linker? It is difficult
for an outsider to determine if this is purely on the linker side or if GCC is
not conforming somehow to what the linker expects.

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[andrew at ishiboo dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

--- Comment #27 from Andrew Paprocki <andrew at ishiboo dot com> ---
60 second reproduction steps:

$ curl -O https://ftp.pcre.org/pub/pcre/pcre-8.42.tar.gz
$ tar zxvf pcre-8.42.tar.gz && cd pcre-8.42
$ CC="gcc-7" \
CXX="g++-7" \
CFLAGS="-maix32 -pthread" \
CXXFLAGS="-maix32 -pthread" \
LDFLAGS="-Wl,-bsvr4" \
./configure && make -j

It will fail:

ld: 0711-308 SEVERE ERROR: Object
pcre_stringpiece_unittest-pcre_stringpiece_unittest.o, csect
<_pcrestringpieceunittest.ro_>
        The csect is part of the .text section.
ld: 0711-308 SEVERE ERROR: Object
pcre_scanner_unittest-pcre_scanner_unittest.o, csect <_pcrescannerunittest.ro_>
        The csect is part of the .text section.
collect2: error: ld returned 12 exit status
collect2: error: ld returned 12 exit status
ld: 0711-308 SEVERE ERROR: Object pcrecpp_unittest-pcrecpp_unittest.o, csect
<_pcrecppunittest.ro_>
        The csect is part of the .text section.
collect2: error: ld returned 12 exit status

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

--- Comment #28 from David Edelsohn <dje at gcc dot gnu.org> ---
GCC 7 is no longer supported.  The patch was backported and released in GCC 8.4
and GCC 9.1.

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[andrew at ishiboo dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

--- Comment #29 from Andrew Paprocki <andrew at ishiboo dot com> ---
David, Using GCC 9.2.0 I can reproduce using the steps from comment 27. Did you
run them yourself?

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

--- Comment #30 from David Edelsohn <dje at gcc dot gnu.org> ---
Yes, I can reproduce the error, but it only occurs when -bsvr4 is used.  Have
you looked at what -bsvr4 enables in the ld man page?  Not just the -R comment.

-brtl -brtllib -bexpfull

-R, instead of being ignored, takes one suboption that defines the runtime
library search path

It seems that you're utilizing the -bsvr4 option to change the behavior of -R
without regard for the other effects of the option.  And the other changes to
the default behavior of the AIX are breaking the build.

-bsvr4 tries to provide a lot of SVR4 behavior, but is too course and big a
club.


[ ] Instead of using -bsvr4, I strongly suggest that you adjust / adapt the
Makefile of your project and use the AIX linker -blibpath command line option
to set the runtime library search path.


I realize that there is no other AIX linker option to change the behavior of
just -R, but you incorrectly are blaming the compiler for an error elicited by
other, documented effects of the -bsvr4 linker option.  AIX is not Solaris or
Linux.  There is no magic command line option to make AIX pretend to be Linux.

The failure is not caused by a GCC bug and it's not caused by an AIX linker
bug.  GCC is behaving as designed.  AIX linker is behaving as designed and
documented.  The -bsvr4 option has too many other effects to be used solely to
work around the -R option.

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

--- Comment #31 from David Edelsohn <dje at gcc dot gnu.org> ---
Just to be clear, the -brtl allows runtime overriding symbols. GCC is correctly
placing some symbols that should not be overridden in the text section. To
allow the runtime overriding, which is not needed for this application/library,
one needs to instruct the AIX linker to make the text section read-write.  All
of these other changes in behavior are triggered by the need to use -R to
specify runtime library search path.

[Bug target/89096] [8/9/10 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|8.5                         |11.0
                 CC|                            |law at redhat dot com

[Bug target/89096] [8/9/10/11/12 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|11.0                        |11.2

--- Comment #32 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 11.1 has been released, retargeting bugs to GCC 11.2.

[Bug target/89096] [8/9/10/11/12 regression] AIX 7 linker rejects _<filename>.ro_ sections by default

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89096

David Edelsohn <dje at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|---                         |WONTFIX