[Bug target/102772] [12 regression] g++.dg/torture/pr80334.C FAILs

["jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102772

--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
If the movaps that it fails on are:
        movaps  %xmm1, thr.1@ntpoff(%ebx)
        movdqu  16(%eax), %xmm2
        movaps  %xmm2, thr.1@ntpoff+16(%ebx)
then I'd say it must be some Solaris bug, because:
        .section        .tbss,"awT",@nobits
        .align 16
        .type   thr.1, @object
        .size   thr.1, 36
thr.1:
        .zero   36
so thr.1 symbol should be 16-byte aligned and so movaps to that address should
work.
On pointer2.o, is the .tbss section properly 16-byte aligned?
On i686-linux I see in readelf -Wa:
  [ 8] .tbss             NOBITS          00000000 000360 000024 00 WAT  0   0
16
What about the executable (in that case the PT_TLS segment is more important
(whether it has 16-byte p_align).
If Solaris dynamic linker doesn't ensure proper alignment of TLS vars (or
assembler or linker screw it up in the middle), it would be nice to find out if
it does for all alignments or just say higher than 8-byte, and perhaps add some
workaround on the GCC side somewhere.
On the pointer2.f90 testcase it is symtab_node::can_increase_alignment_p that
decides if the alignment of the var can be done, so perhaps we'd need a target
hook that for Solaris would say that one can't increase alignment of TLS vars.
But the question is if in
struct __attribute__((aligned (32))) S { long long buf[4]; };
__thread struct S s;
S *foo (void) { return &s; }
it won't return not properly 32-byte aligned pointer too (and is that in all
threads or just some (initial vs. other threads)?