[Bug target/6123] __pic__/__PIC__ not defined when -fpic/-fPIC is specified

["amodra at bigpond dot net dot au" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From amodra at bigpond dot net dot au  2004-11-10 05:07 -------
I made the following reply the day after I said I'd poke around.  Somehow it
seems to be missing from the gcc-patches archive.  Anyway, here it is again:


I grepped through the entire slackware linux source base for occurrences
of __PIC__, and found that all those that might affect PowerPC64 were
testing for (b).  There were only three occurrences, all in glibc!  Many
more for x86 which I didn't pay much attention to, but the few I did
look at were actually testing for (a).  This isn't so surprising, since
on x86 we want different assembly for PIC code, regardless of whether
PIC code is for shared libs (most likely) or otherwise.  OTOH, the
only sensible test of __PIC__ on PowerPC64 can be for (b), since we
are (a) all the time.

Because we currently define __PIC__ all the time, the three occurrences
affecting PowerPC64 Linux result in missed optimizations for non-shared
lib code.

This suggests that powerpc64-linux-gcc should only define __PIC__ when
-fPIC is given, and that Kaveh's patch is OK.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=6123