Re: [PATCH] support --without-multilib --with-specs=-pthread on AIX

[Michael Haubenwallner <michael dot haubenwallner at ssi-schaefer dot com>]

Am 2015-02-17 um 15:57 schrieb David Edelsohn:
> On Tue, Feb 17, 2015 at 3:03 AM, Michael Haubenwallner
> <michael.haubenwallner@ssi-schaefer.com> wrote:
>> Hi David,
>>
>> according to LIB_SPEC found in config/rs6000/aix*.h, pthread linking was done with
>> "-lpthreads -lc_r libc.a" for aix43, which simplified to "-lpthreads -lc" with aix51.
>>
>> But libgcc_s still is linked the aix43 way with "-lpthreads -lc_r libc.a".
>>
>> As libc_r.a is a symlink to libc.a now, do you know if its shared objects are loaded
>> both as "libc.a(shr.o)" and "libc_r.a(shr.o)", or as "libc.a(shr.o)" only?
>> Can this be a problem worth a bug entry?
> 
> What do you mean by "loaded as"?  There is only one shared object
> loaded into the shared library segment.

What I mean with "loaded as" is that the runtime loader does encounter both names
"libc.a(shr.o)" and "libc_r.a(shr.o)" in the loader sections of various dependant
shared libs for one executable - and has to detect them as the same shared object.

>> Anyway, this patch allows me to configure --without-multilib --with-specs=-pthread
> 
> libgcc build does not distinguish between different releases of AIX.
> This patch will break AIX 4.3.  There apparently are people using
> current GCC on AIX.  Why are you submitting a patch that explicitly
> reverts AIX 4.3 support?

Erm, this patch is meant to make use of LIB_SPEC found in config/rs6000/aixXY.h even for
libgcc_s, and with config/rs6000/aix43.h the linked pthread libraries would not change.

Or do these people on AIX 4.3 use gcc-binaries built on some AIX 5/6/7?

Thanks!
/haubi/